Patent Publication Number: US-2022217147-A1

Title: Secure authorization of access to user accounts by one or more authorization mechanisms

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a continuation of U.S. patent application Ser. No. 16/570,630, filed Sep. 13, 2019, and titled “SECURE AUTHORIZATION OF ACCESS TO USER ACCOUNTS BY ONE OR MORE AUTHORIZATION MECHANISMS”, which claims benefit of U.S. Provisional Patent Application No. 62/731,778, filed Sep. 14, 2018, and titled “SECURE PERMISSIONING OF ACCESS TO USER ACCOUNTS.” The entire disclosure of each of the above items is hereby made part of this specification as if set forth fully herein and incorporated by reference for all purposes, for all that it contains. 
     This application is also related to U.S. patent application Ser. No. 15/258,256, filed Sep. 7, 2016, titled “SECURE PERMISSIONING OF ACCESS TO USER ACCOUNTS, INCLUDING SECURE DEAUTHORIZATION OF ACCESS TO USER ACCOUNTS”, and published as U.S. Patent Application Publication No. 2017/0070500 on Mar. 9, 2017 (“the &#39;500 Publication”). This application is also related to U.S. patent application Ser. No. 14/790,840, filed Jul. 2, 2015, titled “SYSTEM AND METHOD FOR PROGRAMMATICALLY ACCESSING FINANCIAL DATA”, and issued as U.S. Pat. No. 9,449,346 on Sep. 20, 2016 (“the &#39;346 patent”). This application is also related to U.S. patent application Ser. No. 14/790,897, filed Jul. 2, 2015, titled “SYSTEM AND METHOD FOR FACILITATING PROGRAMMATIC VERIFICATION OF TRANSACTIONS”, and issued as U.S. Pat. No. 9,595,023 on Mar. 14, 2017 (“the &#39;023 patent”). The entire disclosure of each of the above items is hereby made part of this specification as if set forth fully herein and incorporated by reference for all purposes, for all that it contains. 
     Any and all applications for which a foreign or domestic priority claim is identified in the Application Data Sheet as filed with the present application are hereby incorporated by reference under 37 CFR 1.57 for all purposes and for all that they contain. 
    
    
     TECHNICAL FIELD 
     Embodiments of the present disclosure relate to systems and techniques for securely authorizing access to user accounts, and/or securely authorizing execution of transactions related to user accounts, via one or more application programming interfaces (“APIs”) and/or one or more authorization mechanisms. 
     BACKGROUND 
     The approaches described in this section are approaches that could be pursued, but not necessarily approaches that have been previously conceived or pursued. Therefore, unless otherwise indicated, it should not be assumed that any of the approaches described in this section qualify as prior art merely by virtue of their inclusion in this section. 
     Users may grant access to their user accounts, and related user account data, by providing credentials related to those accounts. 
     SUMMARY 
     The systems, methods, and devices described herein each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this disclosure, several non-limiting features will now be described briefly. 
     Embodiments of the present disclosure relate to systems (e.g., a permissions management system, also referred to herein as “the system”) and techniques for securely authorizing access to user accounts, and/or securely authorizing initiation or execution of transactions related to user accounts, via one or more application programming interfaces (“APIs”) and/or one or more authorization mechanisms. Such access may include access to user account data associated with the user accounts. Such transactions may include, e.g., an electronic payments, or the like. Such APIs may include public and/or non-public (e.g., proprietary) APIs. 
     Advantageously, such one or more authorization mechanisms may include, e.g., a primary authorization mechanism, and one or more fallback authorization mechanisms. 
     For example, where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), and where an external user account system associated with the user account provides support for a primary authorization mechanism, the system may use the primary authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The primary authorization mechanism may include the system obtaining the account credentials from the user, and generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, depending on the external user account system associated with the user account, the primary authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The primary authorization mechanism may include the system automatically accessing institution identifiers and/or account identifiers associated with the user account (e.g., a routing number and an account number associated with the user account) via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the primary authorization mechanism, automatic access of the institution and/or account identifiers, combined with the user-provided account credentials, may authorize the system to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism (or the primary authorization mechanism fails), the system may automatically use a first fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The first fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. As with the primary authorization mechanism, the first fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism, depending on the external user account system associated with the user account, the first fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The first fallback authorization mechanism may include the system automatically accessing institution and/or account identifiers associated with the user account via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the first fallback authorization mechanism, the system may compare the automatically accessed institution and/or account identifiers with the account identifiers obtained from the user. If the institution and/or account identifiers match, the institution and/or account identifiers are thereby verified and the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first fallback authorization mechanism (or the primary authorization mechanism and/or the first fallback authorization mechanism fail), the system may automatically use a second fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The second fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The second fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account. As with the primary authorization mechanism and the first fallback authorization mechanism, the second fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism and the first fallback authorization mechanism, depending on the external user account system associated with the user account, the second fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The second fallback authorization mechanism may include the system automatically accessing user account data of the user account, via the simulated instance(s) of software application(s) and/or APIs of the external user account system, to automatically verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) shown in the user account match the amounts of the deposit(s) initiated by the system). The one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user account data) related to the authorization transactions, such as transaction types (e.g., credit transaction, debit transaction, and/or the like), transaction descriptions, transaction amounts, transaction identifiers, and/or other transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the second fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user cannot or does not desire to provide account credentials associated with a user account, where user account credentials associated with the user account do not exist or are not supported by the external user account system, or where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first or second fallback authorization mechanisms (or the primary authorization mechanism and/or the first and/or second fallback authorization mechanisms fail), the system may automatically use a third fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The third fallback authorization mechanism may include the system obtaining institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The third fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account, subsequently requesting that the user provide information related to the one or more authorization transactions (e.g., amounts of the deposit(s) shown in the user account, as obtained by the user via another channel different from the system), and using the user-provided information to verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) provided by the user match the amounts of the deposit(s) initiated by the system). As with the second fallback authorization mechanism, with the third authorization mechanism the one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user-provided information) related to the authorization transactions, such as transaction amounts, transaction identifiers, and/or transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the third fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., and as with the primary authorization mechanism and the first and second fallback authorization mechanisms, simulated instance(s) of software application(s) and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     In various embodiments, the one or more authorization mechanisms may be ordered or prioritized differently than as described herein. For example, in an embodiment, the first fallback authorization mechanism as described herein may instead be prioritized as the primary authorization mechanism. Other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     Similarly, in various embodiments, certain features and variations of the one or more authorization mechanisms may be different from those described herein. For example, in an embodiment, the primary authorization mechanism may not include automatic access of institution and/or account identifiers. Rather, the primary authorization mechanism may initially provide secure authorization to access a user account, which authorization may be followed (immediately, or at some later point in time) by the first fallback authorization mechanism to provide secure authorization to initiate or execute transactions related to the user account (e.g., by obtaining institution and/or account identifiers from the user and matching/verifying those institution and/or account identifiers). Thus, in this embodiment, the primary authorization mechanism may be understood as a first primary authorization mechanism to access the user account (and associated user account data), and the first fallback authorization mechanism may be understood as a second primary authorization mechanism to initiate or execute transactions related to the user account (which may then be followed by one or more fallback authorization mechanisms, such as the second and third fallback authorization mechanisms, as described herein). As noted above, other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     Advantageously, the one or more authorization mechanisms including, e.g., the primary authorization mechanism and the one or more fallback authorization mechanisms, may enable multiple paths for secure and automated and/or semi-automated user account authorization. Advantageously, the one or more authorization mechanisms may enable adaptation of the system to the capabilities of various external user account systems. Advantageously, the system may further enable authorizations to access user accounts and/or initiate or execute transactions related to user accounts to be provided to an external user-facing system/application, without disclosing institution and/or account identifiers or account credentials to the external user-facing system/application. For example, the disclosure includes, in some embodiments, automatic generation of electronic records that securely store account information (e.g., account credentials and/or account identifiers). In some implementations the electronic records may include one or more permissions related to the account and the external user-facing system/application. A token (e.g., a unique identifier associated with the electronic record, also referred to herein as a “unique record identifier”) may be shared with the external user-facing system/application, but in some implementations neither the electronic record itself, nor the institution and/or account identifiers or credentials, may be shared with the external user-facing system/application. Accordingly, the external user-facing system/application (e.g., a merchant system or a software application developed by a developer) may request user account data and/or initiate transactions by providing the token, but does not itself know, e.g., account numbers, etc. Further, in some implementations the user may set various permissions related to the token/electronic record, and may also revoke permissions associated with the token/electronic record (e.g., de-authorize the external user-facing system/application), thus providing increased security to the user&#39;s account. The disclosure further includes various interactive user interfaces and functionality to facilitate the above-described functionality. 
     As mentioned above, embodiments of the present disclosure relate to systems and techniques for securely and efficiently obtaining user account data via instantiation of virtualized or simulated instances of first-party software applications. For example, the systems of the present disclosure include generation of proxy, virtualized, or simulated instances of software applications that are configured to interface with external systems via public or non-public (e.g., proprietary) APIs. The virtualized or simulated instances of the software applications may be authenticated with the external systems as if the virtualized/simulated instances are actually first-party software applications executing on a user computing device. Via the public/non-public APIs user account information may be obtained and processed, such that the data may be normalized and provided to other software systems via a normalized API of the system. Accordingly, the systems of the present disclosure may be significantly more efficient at obtaining user account data from external systems than previous techniques. Further, the user account data may be normalized and requested and/or provided via a normalized API, enabling others to efficiently access such data (originally obtained from multiple external systems) from a single standardized interface in a highly efficient manner. 
     Thus, advantageously, the systems and techniques of the present disclosure may enable access to, and initiation or execution of transactions related to, numerous and disparate user accounts via a single standardized API, while actual communications with those numerous and disparate user accounts may be accomplished by the system via a plethora of different public and/or non-public APIs of numerous different external user account systems (e.g., institutions) and/or numerous different virtualized or simulated instances of software applications specific to those various external user account systems. 
     Accordingly, in various embodiments, large amounts of data are automatically and dynamically retrieved and processed in response to API requests and other user inputs, and the retrieved data is efficiently and compactly accessible to a customer or user also via normalized API responses from the system. The data is retrieved in an efficient way via instantiation of virtualized/simulated instances of mobile applications, for example. Thus, in some embodiments, the API interfaces described herein are more efficient as compared to previous interfaces in which data is not normalized and compactly and efficiently provided to the customer user in response to such requests. Advantageously, using the system, the customer or user may access data from multiple disparate data sources (e.g., data stores) and/or systems, each of which may use a proprietary interface, in a standardized way. 
     Further, as described herein, the system may be configured and/or designed to generate user interface data useable for rendering the various interactive user interfaces described. The user interface data may be used by the system, and/or another computer system, device, and/or software program (for example, a browser program), to render the interactive user interfaces. The interactive user interfaces may be displayed on, for example, electronic displays (including, for example, touch-enabled displays). 
     Additionally, it has been noted that design of computer user interfaces “that are useable and easily learned by humans is a non-trivial problem for software developers.” (Dillon, A. (2003) User Interface Design. MacMillan Encyclopedia of Cognitive Science, Vol. 4, London: MacMillan, 453-458.) The present disclosure describes various embodiments of interactive and dynamic user interfaces that are the result of significant development. This non-trivial development has resulted in the user interfaces described herein which may provide significant cognitive and ergonomic efficiencies and advantages over previous systems. The interactive and dynamic user interfaces include improved human-computer interactions that may provide reduced mental workloads, improved decision-making, reduced work stress, and/or the like, for a user. For example, user interaction with the interactive user interface via the inputs described herein may provide an optimized display of, and interaction with, transaction and account data and may enable a customer user to more quickly and accurately access, navigate, assess, and digest the account data than previous systems. 
     Further, the interactive and dynamic user interfaces described herein are enabled by innovations in efficient interactions between the user interfaces and underlying systems and components. For example, disclosed herein are improved methods of receiving user inputs, translation and delivery of those inputs to various system components, automatic and dynamic execution of complex processes in response to the input delivery, automatic interaction among various aspects and processes of the system, and automatic and dynamic updating of the user interfaces. The interactions and presentation of data via the interactive user interfaces described herein may accordingly provide cognitive and ergonomic efficiencies and advantages over previous systems. 
     Various embodiments of the present disclosure provide improvements to various technologies and technological fields. For example, as mentioned above, existing account and/or transaction data retrieval technology is limited in various ways (e.g., interfaces differ for each system or source, data is provided in different formats, etc.), and various embodiments of the disclosure provide significant improvements over such technology. Additionally, various embodiments of the present disclosure are inextricably tied to computer technology. In particular, various embodiments rely on receipt of computer-based API requests, accessing of transaction and/or other data via, e.g., virtualized/simulated instances of mobile applications, normalization of retrieved data, and responses to the requests via the API in a standardized way. Such features and others are intimately tied to, and enabled by, computer technology, and would not exist except for computer technology. For example, the API request and responses, and instantiation of virtualized/simulated instances of e.g., mobile applications, described below in reference to various embodiments, cannot reasonably be performed by humans alone, without the computer technology upon which they are implemented. Further, the implementation of the various embodiments of the present disclosure via computer technology enables many of the advantages described herein, including more efficient interaction with, various types of data. 
     According to an embodiment, a computer system comprises a computer readable storage medium having program instructions embodied therewith; and one or more processors configured to execute the program instructions to cause the computer system to: receive, from a computing device operated by a user, an indication of an institution, and account credentials associated with a user account associated with the institution; determine whether the institution supports a primary authorization mechanism; in response to determining that the institution does not support the primary authorization mechanism, initiate a first fallback authorization mechanism; request and receive a first account identifier associated with the user account from the computing device operated by the user; access a second account identifier associated with the user account through at least an application programming interface (“API”) associated with the institution and using the account credentials; compare the first account identifier with the second account identifier to determine that the first account identifier and the second account identifier match; and in response to determining that the first account identifier and the second account identifier match, generate a token usable to authorize access to user account data associated with the user account or initiation of transactions related to the user account. 
     According to an aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: request and receive a first institution identifier associated with the institution from the computing device operated by the user; access a second institution identifier associated with the institution through at least one of: the API associated with the institution, or a database of institution identifiers; and compare the first institution identifier with the second institution identifier to determine that the first institution identifier and the second institution identifier match, wherein generating the token is performed further in response to determining that the first institution identifier and the second institution identifier match. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: further in response to determining that the first account identifier and the second account identifier match, access user account information associated with the user account through at least the API associated with the institution. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: provide a permissions plug-in to the computing device operated by the user, wherein the permissions plug-in is configured to: generate one or more user interfaces configured to receive a selection of the institution from the user; generate one or more user interfaces configured to receive the account credentials associated with the user account from the user; generate one or more user interfaces configured to receive the first account identifier associated with the user account from the user; and securely communicate, to the computer system, the indication of the institution, the account credentials, and the first account identifier. 
     According to another aspect, the indication of the institution, the account credentials, and the first account identifier are not stored by the computing device operated by the user or accessible to an external user-facing system/application executing on the computing device operated by the user. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: instantiate a simulated instance of a software application associated with the institution and configured to communicate with a computing device associated with the institution through the API associated with the institution, wherein accessing the second account identifier is performed through the simulated instance of the software application and the API associated with the institution, and using the account credentials. 
     According to another aspect, the second account identifier is accessed through extraction of the second account identifier from a document accessed through the API associated with the institution. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: in response to determining that the institution does support the primary authorization mechanism, initiate the primary authorization mechanism; access an account identifier associated with the user account through at least the API associated with the institution and using the account credentials; access an institution identifier associated with the institution through at least one of: the API associated with the institution, or a database of institution identifiers; and generate a token usable to authorize access to user account data associated with the user account or initiation of transactions related to the user account. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: in response to determining that at least one of: the institution does not support either the primary authorization mechanism or the first fallback authorization mechanism, or the first fallback authorization mechanism failed: initiate a second fallback authorization mechanism; initiate one or more authorization transactions to the user account using an account identifier associated with the user account and an institution identifier associated with the institution; verify the one or more authorization transactions; and in response to verifying the one or more authorization transactions, generate a token usable to authorize access to user account data associated with the user account or initiation of transactions related to the user account. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: request and receive the account identifier associated with the user account from the computing device operated by the user; and request and receive the institution identifier associated with the institution from at least one of: the computing device operated by the user, or a database of institution identifiers. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: provide a permissions plug-in to the computing device operated by the user, wherein the permissions plug-in is configured to: generate one or more user interfaces configured to receive a selection of the institution from the user; generate one or more user interfaces configured to receive the account credentials associated with the user account from the user; generate one or more user interfaces configured to receive the account identifier associated with the user account from the user; generate one or more user interfaces configured to receive the institution identifier associated with the user account from the user; and securely communicate, to the computer system, the indication of the institution, the account credentials, the account identifier, and the institution identifier. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: verify the one or more authorization transactions based on one or more authorization parameters associated with the one or more authorization transactions, wherein the one or more authorization parameters include at least one of: transaction type, transaction description, transaction amount, transaction identifier, datestamps, timestamps, source, or other transaction metadata. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: automatically verify the one or more authorization transactions without additional user input, wherein automatically verifying the one or more authorization transactions comprises: accessing, from user account data associated with the user account, a first one or more authorization parameters associated with the one or more authorization transactions through at least an application programming interface (“API”) associated with the institution and using the account credentials; comparing the first one or more authorization parameters with a second one or more authorization parameters associated with the one or more authorization transactions to determine that the first one or more authorization parameters and the second one or more authorization parameters match, wherein the second one or more authorization parameters are stored by the computer system upon initiating the one or more authorization transactions. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: in response to initiating the one or more authorization transactions, and before verifying the one or more authorization transactions, generate an interim token. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: in response to determining that at least one of: the institution does not support any of the primary authorization mechanism, the first fallback authorization mechanism, or the second fallback authorization mechanism, or the second fallback authorization mechanism failed: initiate a third fallback authorization mechanism; if not already initiated, initiate one or more authorization transactions to the user account using an account identifier associated with the user account and an institution identifier associated with the institution; request and receive a first one or more authorization parameters from the computing device operated by the user; verify the one or more authorization transactions based at least in part on the first one or more authorization parameters; and in response to verifying the one or more authorization transactions, generate a token usable to authorize access to user account data associated with the user account or initiation of transactions related to the user account. 
     According to yet another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: request and receive the account identifier associated with the user account from the computing device operated by the user; and request and receive the institution identifier associated with the institution from at least one of: the computing device operated by the user, or a database of institution identifiers. 
     According to another aspect, the one or more processors are configured to execute the program instructions to further cause the computer system to: provide a permissions plug-in to the computing device operated by the user, wherein the permissions plug-in is configured to: generate one or more user interfaces configured to receive a selection of the institution from the user; generate one or more user interfaces configured to receive the account credentials associated with the user account from the user; generate one or more user interfaces configured to receive the account identifier associated with the user account from the user; generate one or more user interfaces configured to receive the institution identifier associated with the user account from the user; generate one or more user interfaces configured to receive the first one or more authorization parameters from the user; and securely communicate, to the computer system, the indication of the institution, the account credentials, the account identifier, the institution identifier, and first one or more authorization parameters. 
     According to yet another aspect, the first one or more authorization parameters include at least one of: transaction type, transaction description, transaction amount, transaction identifier, datestamps, timestamps, source, or other transaction metadata. 
     According to another aspect, verifying the one or more authorization transactions comprises: comparing the first one or more authorization parameters with a second one or more authorization parameters associated with the one or more authorization transactions to determine that the first one or more authorization parameters and the second one or more authorization parameters match, wherein the second one or more authorization parameters are stored by the computer system upon initiating the one or more authorization transactions. 
     Various combinations of the above and below recited features, embodiments, and aspects are also disclosed and contemplated by the present disclosure. 
     Additional embodiments of the disclosure are described below in reference to the appended claims, which may serve as an additional summary of the disclosure. 
     In various embodiments, systems and/or computer systems are disclosed that comprise a computer readable storage medium having program instructions embodied therewith, and one or more processors configured to execute the program instructions to cause the systems and/or computer systems to perform operations comprising one or more aspects of the above- and/or below-described embodiments (including one or more aspects of the appended claims). 
     In various embodiments, computer-implemented methods are disclosed in which, by one or more processors executing program instructions, one or more aspects of the above- and/or below-described embodiments (including one or more aspects of the appended claims) are implemented and/or performed. 
     In various embodiments, computer program products comprising a computer readable storage medium are disclosed, wherein the computer readable storage medium has program instructions embodied therewith, the program instructions executable by one or more processors to cause the one or more processors to perform operations comprising one or more aspects of the above- and/or below-described embodiments (including one or more aspects of the appended claims). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The following drawings and the associated descriptions are provided to illustrate embodiments of the present disclosure and do not limit the scope of the claims. Aspects and many of the attendant advantages of this disclosure will become more readily appreciated as the same become better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein: 
         FIG. 1  is a block diagram illustrating various aspects of a computing system and network environment in which the computing system may be implemented, according to an embodiment; 
         FIG. 2  illustrates aspects of some example proxy instances, according to an embodiment; 
         FIG. 3  is a flowchart illustrating an example method of accessing user account data, according to an embodiment; 
         FIG. 4A  illustrates aspects of an application proxy system, according to an embodiment; 
         FIG. 4B  illustrates aspects of some example proxy instances, according to an embodiment; 
         FIG. 5  is a flowchart illustrating an example method of processing transactions, according to an embodiment; 
         FIG. 6  is a simplified block diagram of the computing system and network environment of  FIG. 1 , according to an embodiment; 
         FIGS. 7-8  illustrate examples of API request and response flows of the system, according to an embodiment; 
         FIGS. 9-10  are flowcharts illustrating example methods of processing transactions, according to various embodiments; 
         FIG. 11  is a block diagram of an example architecture of the system, according to an embodiment; 
         FIG. 12A  illustrates an example network environment in which a permissions management system may operate, according to an embodiment; 
         FIG. 12B  is a block diagram illustrating example interactions among the aspects of the network environment, according to various embodiments; 
         FIG. 13  is a flowchart illustrating one or more authorization mechanisms, according to an embodiment; 
         FIGS. 14A, 14B, and 14C  illustrate example interactive user interfaces of the system, according to various embodiments; 
         FIG. 15  is a flowchart illustrating additional aspects of one or more authorization mechanisms, according to an embodiment; and 
         FIGS. 16A, 16B, 16C, and 16D  illustrate example interactive user interfaces of the system, according to various embodiments. 
     
    
    
     DETAILED DESCRIPTION 
     Although certain preferred embodiments and examples are disclosed below, inventive subject matter extends beyond the specifically disclosed embodiments to other alternative embodiments and/or uses and to modifications and equivalents thereof. Thus, the scope of the claims appended hereto is not limited by any of the particular embodiments described below. For example, in any method or process disclosed herein, the acts or operations of the method or process may be performed in any suitable sequence and are not necessarily limited to any particular disclosed sequence. Various operations may be described as multiple discrete operations in turn, in a manner that may be helpful in understanding certain embodiments; however, the order of description should not be construed to imply that these operations are order dependent. Additionally, the structures, systems, and/or devices described herein may be embodied as integrated components or as separate components. For purposes of comparing various embodiments, certain aspects and advantages of these embodiments are described. Not necessarily all such aspects or advantages are achieved by any particular embodiment. Thus, for example, various embodiments may be carried out in a manner that achieves or optimizes one advantage or group of advantages as taught herein without necessarily achieving other aspects or advantages as may also be taught or suggested herein. 
     I. Overview 
     As mentioned above, according to various embodiments systems (e.g., a permissions management system, also referred to herein as “the system”) and techniques are disclosed for securely authorizing access to user accounts, and/or securely authorizing initiation or execution of transactions related to user accounts, via one or more application programming interfaces (“APIs”) and/or one or more authorization mechanisms. Such access may include access to user account data associated with the user accounts. Such transactions may include, e.g., an electronic payments, or the like. Such APIs may include public and/or non-public (e.g., proprietary) APIs. 
     Advantageously, such one or more authorization mechanisms may include, e.g., a primary authorization mechanism, and one or more fallback authorization mechanisms. 
     For example, where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), and where an external user account system associated with the user account provides support for a primary authorization mechanism, the system may use the primary authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The primary authorization mechanism may include the system obtaining the account credentials from the user, and generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, depending on the external user account system associated with the user account, the primary authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The primary authorization mechanism may include the system automatically accessing institution identifiers and/or account identifiers associated with the user account (e.g., a routing number and an account number associated with the user account) via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the primary authorization mechanism, automatic access of the institution and/or account identifiers, combined with the user-provided account credentials, may authorize the system to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism (or the primary authorization mechanism fails), the system may automatically use a first fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The first fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. As with the primary authorization mechanism, the first fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism, depending on the external user account system associated with the user account, the first fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The first fallback authorization mechanism may include the system automatically accessing institution and/or account identifiers associated with the user account via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the first fallback authorization mechanism, the system may compare the automatically accessed institution and/or account identifiers with the account identifiers obtained from the user. If the institution and/or account identifiers match, the institution and/or account identifiers are thereby verified and the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first fallback authorization mechanism (or the primary authorization mechanism and/or the first fallback authorization mechanism fail), the system may automatically use a second fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The second fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The second fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account. As with the primary authorization mechanism and the first fallback authorization mechanism, the second fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism and the first fallback authorization mechanism, depending on the external user account system associated with the user account, the second fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The second fallback authorization mechanism may include the system automatically accessing user account data of the user account, via the simulated instance(s) of software application(s) and/or APIs of the external user account system, to automatically verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) shown in the user account match the amounts of the deposit(s) initiated by the system). The one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user account data) related to the authorization transactions, such as transaction types (e.g., credit transaction, debit transaction, and/or the like), transaction descriptions, transaction amounts, transaction identifiers, and/or other transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the second fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Where a user cannot or does not desire to provide account credentials associated with a user account, where user account credentials associated with the user account do not exist or are not supported by the external user account system, or where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first or second fallback authorization mechanisms (or the primary authorization mechanism and/or the first and/or second fallback authorization mechanisms fail), the system may automatically use a third fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The third fallback authorization mechanism may include the system obtaining institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The third fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account, subsequently requesting that the user provide information related to the one or more authorization transactions (e.g., amounts of the deposit(s) shown in the user account, as obtained by the user via another channel different from the system), and using the user-provided information to verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) provided by the user match the amounts of the deposit(s) initiated by the system). As with the second fallback authorization mechanism, with the third authorization mechanism the one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user-provided information) related to the authorization transactions, such as transaction amounts, transaction identifiers, and/or transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the third fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., and as with the primary authorization mechanism and the first and second fallback authorization mechanisms, simulated instance(s) of software application(s) and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     In various embodiments, the one or more authorization mechanisms may be ordered or prioritized differently than as described herein. For example, in an embodiment, the first fallback authorization mechanism as described herein may instead be prioritized as the primary authorization mechanism. Other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     Similarly, in various embodiments, certain features and variations of the one or more authorization mechanisms may be different from those described herein. For example, in an embodiment, the primary authorization mechanism may not include automatic access of institution and/or account identifiers. Rather, the primary authorization mechanism may initially provide secure authorization to access a user account, which authorization may be followed (immediately, or at some later point in time) by the first fallback authorization mechanism to provide secure authorization to initiate or execute transactions related to the user account (e.g., by obtaining institution and/or account identifiers from the user and matching/verifying those institution and/or account identifiers). Thus, in this embodiment, the primary authorization mechanism may be understood as a first primary authorization mechanism to access the user account (and associated user account data), and the first fallback authorization mechanism may be understood as a second primary authorization mechanism to initiate or execute transactions related to the user account (which may then be followed by one or more fallback authorization mechanisms, such as the second and third fallback authorization mechanisms, as described herein). As noted above, other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     Advantageously, the one or more authorization mechanisms including, e.g., the primary authorization mechanism and the one or more fallback authorization mechanisms, may enable multiple paths for secure and automated and/or semi-automated user account authorization. Advantageously, the one or more authorization mechanisms may enable adaptation of the system to the capabilities of various external user account systems. Advantageously, the system may further enable authorizations to access user accounts and/or initiate or execute transactions related to user accounts to be provided to an external user-facing system/application, without disclosing institution and/or account identifiers or account credentials to the external user-facing system/application. For example, the disclosure includes, in some embodiments, automatic generation of electronic records that securely store account information (e.g., account credentials and/or account identifiers). In some implementations the electronic records may include one or more permissions related to the account and the external user-facing system/application. A token (e.g., a unique identifier associated with the electronic record, also referred to herein as a “unique record identifier”) may be shared with the external user-facing system/application, but in some implementations neither the electronic record itself, nor the institution and/or account identifiers or credentials, may be shared with the external user-facing system/application. Accordingly, the external user-facing system/application (e.g., a merchant system or a software application developed by a developer) may request user account data and/or initiate transactions by providing the token, but does not itself know, e.g., account numbers, etc. Further, in some implementations the user may set various permissions related to the token/electronic record, and may also revoke permissions associated with the token/electronic record (e.g., de-authorize the external user-facing system/application), thus providing increased security to the user&#39;s account. The disclosure further includes various interactive user interfaces and functionality to facilitate the above-described functionality. 
     As mentioned above, embodiments of the present disclosure relate to systems and techniques for securely and efficiently obtaining user account data via instantiation of virtualized or simulated instances of first-party software applications. For example, the systems of the present disclosure include generation of proxy, virtualized, or simulated instances of software applications that are configured to interface with external systems via public or non-public (e.g., proprietary) APIs. The virtualized or simulated instances of the software applications may be authenticated with the external systems as if the virtualized/simulated instances are actually first-party software applications executing on a user computing device. Via the public/non-public APIs user account information may be obtained and processed, such that the data may be normalized and provided to other software systems via a normalized API of the system. Accordingly, the systems of the present disclosure may be significantly more efficient at obtaining user account data from external systems than previous techniques. Further, the user account data may be normalized and requested and/or provided via a normalized API, enabling others to efficiently access such data (originally obtained from multiple external systems) from a single standardized interface in a highly efficient manner. 
     Thus, advantageously, the systems and techniques of the present disclosure may enable access to, and initiation or execution of transactions related to, numerous and disparate user accounts via a single standardized API, while actual communications with those numerous and disparate user accounts may be accomplished by the system via a plethora of different public and/or non-public APIs of numerous different external user account systems (e.g., institutions) and/or numerous different virtualized or simulated instances of software applications specific to those various external user account systems. 
     Embodiments of the disclosure will now be described with reference to the accompanying figures, wherein like numerals refer to like elements throughout. The terminology used in the description presented herein is not intended to be interpreted in any limited or restrictive manner, simply because it is being utilized in conjunction with a detailed description of certain specific embodiments of the disclosure. Furthermore, embodiments of the disclosure may include several novel features, no single one of which is solely responsible for its desirable attributes or which is essential to practicing the embodiments of the disclosure herein described. 
     II. Definitions 
     In order to facilitate an understanding of the systems and methods discussed herein, a number of terms are defined below. The terms defined below, as well as other terms used herein, should be construed broadly to include the provided definitions, the ordinary and customary meaning of the terms, and/or any other implied meaning for the respective terms. Thus, the definitions below do not limit the meaning of these terms, but only provide example definitions. 
     Permissions Management System (also referred to herein as “the system”): A computing system, the functionality of which is described in detail in the present disclosure. Functions of the permissions management system (which are described in further detail above and below) include, but are not limited to: accessing and/or extracting user accounts and user account data from external user account systems or other systems; initiating execution of, or executing, transactions via external user account systems or other systems; generating secure electronic records and tokens (e.g., unique identifiers associated with the electronic records) based on user account data; enabling authorization of (or permissions for) access to, and execution of transactions related to, user accounts on the external user account systems or other systems; enabling revocation of authorization/permissions for, or de-authorization of, access to user accounts on the external user account systems or other systems; and/or enabling revocation of authorization/permissions for, or de-authorization of, rights to execute transactions related to user accounts on the external user account systems or other systems; among other functions. One or more of these functionalities may be implemented via the permissions management system, as described below, and may be accessible to customers via a standardized application programming interface (“API”). Accordingly, a customer may access any of the functionality of the permissions management system (including, e.g., accessing user account data, permissioning access to user account data, etc.), via the standardized API. 
     External User Account System: A computing system or service of an external institution. For ease of description, general references herein to external institutions (or more simply “institutions”) may be understood to refer to the external user account systems of those institutions. Accordingly, external user account systems may also be referred to herein as “external institution system,” “external bank systems,” “bank systems,” “banks,” “institutions,” “external services,” and/or the like. As described below, external user account systems may provide public and/or non-public (e.g., proprietary) APIs by which user account data may be accessed by first-party software applications (e.g., mobile device software applications) of the external institutions. However, as further described below, the system of the present disclosure may enable access to user account data via such public/non-public APIs of the external user account systems by, e.g., instantiating virtual and/or proxy instances of the first-party software applications of the external institutions. External user accounts may also be referred to herein as “user accounts.” 
     External Institution: An entity that maintains a user account. Examples of external institutions (also referred to herein as “institutions”) include, but are not limited to, banks, credit card providers, investment services, loan providers, and/or other suitable financial institutions or user account holding institutions. 
     Application Programming Interface (“API”): A set of routines, protocols, and/or tools for building a software application. Generally an API defines a standardized set of operations, inputs, outputs, and underlying types, such that functionality is accessible via the API in an efficient way. The system provides an API by which a customer may access any of the functionality of the system, as described herein. Accordingly, the system advantageously abstracts away (from a customer&#39;s perspective), much of the complexity that may be involved in the functionality of the system, and enables the customer to quickly and efficiently leverage the functionality of the system to build other systems and services. 
     Customer: One who makes use of the API of the system to access functionality of the system in a software application of the customer, as described herein. Customers of the system may include, but are not limited to, software developers (who may be developing, e.g., a software application such as a store, or mobile app), third-party processors (e.g., third-party payment processors), external institutions, merchants, and/or the like. 
     External User-Facing System/Application: A software application and/or computing system of a customer (e.g., developed by a customer) that interacts with the system via the API of the system. Examples of external user-facing systems/applications include, but are not limited to, desktop software applications, mobile device software applications, server software applications, and/or the like. In general, external user-facing systems/applications provide goods or services to a user. In some instances, for ease of description, such software applications may be referred to herein as “apps.” Additionally, external user-facing systems/applications may also be referred to herein as “developer systems,” “developer computing devices,” and/or the like. Examples of external user-facing systems/applications include apps for payment processing, account data review/analysis, budgeting, account monitoring, providing recommendations for savings, etc. 
     Third-Party Processor: An entity that processes transactions, e.g., financial transactions for a merchant. When provided with account information (e.g., credit/debit card information, bank account information, etc.) and payment information (e.g., how much to pay, to whom, and when, etc.), executes and processes a transaction. In some implementations, the system may interact with one or more third-party processor systems to execute and/or process payments. Alternatively, the system may include functionality to process transactions, and thus may effectively act as its own “third-party” processor (thus, “third-party” is somewhat of a misnomer in this context, but the term “third-party” is used in the present disclosure for clarity purposes). Third-party processors may be referred to herein as “trusted” third-party processors, because in some implementations the third-party processor is entrusted with user account data that, for example, an external user-facing system/application is not. Third-party processors may be referred to herein as “third-party transaction processors.” As used herein, the term “transactions” may include any of various types of activities related to accounts, including but not limited to: financial transactions (e.g., ACH transfers, credit card transactions, debit card transactions, other types of payments or money transfers, etc.), updating account information, setting up alerts, etc. The system may additionally enable various other types of activities (e.g., updating account information, requesting services, etc.) that in some instances may be referred to herein as executing transactions, and/or the like. 
     User: A holder of a user account at an external institution. In general, a user maintains account credentials for accessing their user account, and provides authorizations and/or de-authorizations for an external user-facing system/application of a customer (e.g., an “app” of a developer) to limitedly and securely access the user account (e.g., to initiate payments for goods or services). Such authorizations and/or de-authorizations (among other functionality) are enabled by the system and via the API of the system, as described herein. Advantageously, according to some embodiments, the user&#39;s account credentials are never accessible to the external user-facing system/application. Rather, the system may securely enable the user to indicate authorizations and/or de-authorizations, without revealing the account credentials outside of the system (and/or trusted entities of the system, such as a trusted third-party processor). 
     User Input (also referred to herein as “input.”): Any interaction, data, indication, etc., received by the system from a user, a representative of a user, an entity associated with a user, and/or any other entity. Inputs may include any interactions that are intended to be received and/or stored by the system; to cause the system to access and/or store data items; to cause the system to analyze, integrate, and/or otherwise use data items; to cause the system to update to data that is displayed; to cause the system to update a way that data is displayed; and/or the like. Non-limiting examples of user inputs include keyboard inputs, mouse inputs, digital pen inputs, voice inputs, finger touch inputs (e.g., via touch sensitive display), gesture inputs (e.g., hand movements, finger movements, arm movements, movements of any other appendage, and/or body movements), and/or the like. Additionally, user inputs to the system may include inputs via tools and/or other objects manipulated by the user. For example, the user may move an object, such as a tool, stylus, or wand, to provide inputs. Further, user inputs may include motion, position, rotation, angle, alignment, orientation, configuration (e.g., fist, hand flat, one finger extended, etc.), and/or the like. For example, user inputs may comprise a position, orientation, and/or motion of a hand or other appendage, a body, a  3 D mouse, and/or the like. 
     Data Store: Any computer readable storage medium and/or device (or collection of data storage mediums and/or devices). Examples of data stores include, but are not limited to, optical disks (e.g., CD-ROM, DVD-ROM, etc.), magnetic disks (e.g., hard disks, floppy disks, etc.), memory circuits (e.g., solid state drives, random-access memory (RAM), etc.), and/or the like. Another example of a data store is a hosted storage environment that includes a collection of physical data storage devices that may be remotely accessible and may be rapidly provisioned as needed (commonly referred to as “cloud” storage). 
     Database: Any data structure (and/or combinations of multiple data structures) for storing and/or organizing data, including, but not limited to, relational databases (e.g., Oracle databases, PostgreSQL databases, etc.), non-relational databases (e.g., NoSQL databases, etc.), in-memory databases, spreadsheets, comma separated values (CSV) files, eXtendible markup language (XML) files, TeXT (TXT) files, flat files, spreadsheet files, and/or any other widely used or proprietary format for data storage. Databases are typically stored in one or more data stores. Accordingly, each database referred to herein (e.g., in the description herein and/or the figures of the present application) is to be understood as being stored in one or more data stores. Additionally, although the present disclosure may show or describe data as being stored in combined or separate databases, in various embodiments such data may be combined and/or separated in any appropriate way into one or more databases, one or more tables of one or more databases, etc. As used herein, a data source may refer to a table in a relational database, for example. 
     III. Example Systems and Methods for Programmatically Accessing User Account Data 
       FIG. 1  illustrates certain aspects of a computing system  100  (e.g., the permissions management system) that may securely authorize, and provide, access to user accounts, access to user account data, initiation or execution of transactions related to user accounts, and/or the like, of one or more external user account systems. The system  100  may include an API service  110 , an application proxy system  120 , and at least one institution interface module (e.g., modules  131 ,  132 , and  133 ). The system functions to provide programmatic access to one or more external user account systems (e.g., external user account systems  141 ,  142 , and  143 ) that lack exposed programmatic access. The external user account systems may comprise proprietary and external financial services (e.g., financial institution services, among others, as described above). Such institutions may have first party software applications (e.g., mobile applications) that enable users to access user account data/information from a mobile or desktop device. Such first party applications commonly use proprietary or customized API (e.g., APIs  161 ,  162 , and  163 ). These APIs are commonly not public and not exposed. For example, a developer is commonly prevented from registering an account and using an open API authentication approach to arbitrarily access the API resources of such external user account systems. Additionally, the APIs (e.g., APIs  161 ,  162 , and  163 ) of the external user account systems are a non-trivial customized interface protocols that may not be shared with other institutions; e.g., each external user account system conforms to its own interface. 
     The system  100  functions to provide a normalized interface (e.g., API service  110 ) to the one or more external user account systems (e.g., external user account systems  141 ,  142 , and  143 ). The system  100  enables access to a user account within an external user account system by leveraging the application proxy system  120 . A virtualized “image” or digital simulation (also generally referred to herein as a “simulated instance” or a “virtualized instance”) of an application instance is maintained in the application proxy system  120  and used to access the unexposed API (e.g., APIs  161 ,  162 , and  163 ) of the external user account system. While the system may be applied to financial institutions, the system may additionally or alternatively be applied to providing API access to other external systems with closed or limited API access. 
     The API  110  of the system functions to provide a normalized customer facing interface. The API  110  may be normalized in the sense that the underlying non-public (or public) API to the external user account system (e.g., external user account systems  141 ,  142 , and  143 ) that acts as the source of the user account data is abstracted away, and the API  110  to various different external user account systems is substantially standardized. In some variations, various aspects of the API  110  may be limited when interfacing with external user account systems. For example, one institution may not support a feature such as digital check deposit, while a second institution does. In this case, the API  110  may define the API such that the API feature for check deposit is prevented for the first institution. The system  100 , and more specifically the API  110 , may be used to provide an accessible API service to customers, e.g., outside developers. As such, the system  100  is may be a multi-tenant system that allows numerous accounts to share use of the system  100 . The system  100  and more particularly the API  110  may alternatively be a single tenant system. For example, the system may be used as an internal system to a website providing an online financial management product. 
     The API service  110  may be a RESTful API, but may alternatively be any suitable API such as SOAP or custom protocol. The RESTful API works according to an HTTP request and response model. HTTP requests (or any suitable request communication) to the system  100  may observe the principles of a RESTful design. RESTful is understood in this document to describe a Representational State Transfer architecture as is known in the art. The RESTful HTTP requests may be stateless, thus each message communicated contains all necessary information for processing the request and generating a response. The API service  110  can include various resources which act as endpoints which act as a mechanism for specifying requested information or requesting particular actions. The resources can be expressed as URI&#39;s or resource paths. The RESTful API resources can additionally be responsive to different types of HTTP methods such as GET, PUT, POST, and/or DELETE. 
     The API service  110  can provide an interface into a variety of information and action resources, as provided by the system  100 . Information/data relating to a user account may be accessible through querying particular API resources via the API  110 . For example, a list of transactions and information about each individual transaction may be accessible through different API calls of the API  110 . Information can additionally relate to account summary information, account details such as address and contact information, information about other parties such as the entities involved in a transaction, and/or any suitable information. The API  110  may additionally be used to trigger or facilitate performing some action. For example, an API call may be used in transferring money, updating account information, setting up alerts, or performing any suitable action. Those skilled in the art will appreciate that such example API features that any suitable API feature possibilities and semantic architecture may be used. 
     In one example implementation, an API call via the API  110  can support adding a user, completing authentication, accessing transaction information, and other actions. For example, an application may POST to a “/transaction” REST API resource of the API  110  to authenticate a user, e.g. “/item/create”; if an institution includes multi-factor authentication, then a “/item/mfa” resource can be submitted to complete multi-factor authentication credentials; and then performing a GET on the “/transaction” resource can access transactional data related to the user/user&#39;s account. The API  110  may additionally include informational resources to access information about entities involved in transactions. For example, the API  110  may allow a particular business resource to be accessed to obtain contextual information about the business such as name, location, and classification. 
     The application proxy system  120  functions to manage a simulation of a first-party software application access to an institution. The application proxy system  120  operates in cooperation with one or more institution interface modules (e.g., institution interface modules  131 ,  132 , and  133 ) to establish a data model and/or a data image that acts as a virtualized or simulated application instance (also referred to herein as an “application proxy instance,” “proxy instance,” “virtualized instance,” “simulated instance,” and/or the like) (e.g., proxy instances  121 ,  122 , and  123 ). From the perspective of the institution, the proxy instance (e.g., proxy instances  121 ,  122 , and  123 ) appears as a first-party application (e.g., Bank 2 application  153 ) installed on a physical user device (e.g., user devices  171  and  172 ) that is being used by a user. In other words, the requests received from the proxy instance are treated like requests from a first-party mobile app, desktop app, or web-based application of the user. The application proxy system  120  may store and maintain a plurality of application proxy instances (e.g., proxy instances  121 ,  122 , and  123 ). The proxy instances may include configuration settings and properties that, when used according to a defined institution interface (e.g., an institution interface of an institution interface module  131 ,  132 , and/or  133 ), will appear as requests from first-party applications (e.g., application  153 ) of the institution (e.g., institution  141 ,  142 , and/or  143 ). A different proxy instance may be created and maintained for each user account-institution pair. A given user may have multiple user accounts with different institutions. A proxy instance may include a set of properties that can be used to authenticate the proxy instance with the institution system (e.g., institution  141 ,  142 , and/or  143 ). The application proxy system  120  provides a method to programmatically create a proxy instance for a user. The user may provide some account credentials that can be used in an initial registration of the proxy instance with the non-public or public API of the institution. The proxy instance may be characterized as a set of properties that can be stored and maintained. Some of those properties may be automatically generated, may be provided from the institution during negotiating registration, may be properties of the application that is being simulated, and/or may include any suitable identifying and authenticating information. The properties may include a unique user identifier code, an authentication token, a MAC address (e.g., a MAC address of a user device  171  or  172 ), or any suitable information. When a request is made to a bank on behalf of a user, the properties of the proxy instance may be invoked to gain access to the institution on behalf of the associated user. 
       FIG. 2  depicts example proxy instances  121 ,  122 , and  123  of  FIG. 1 . As shown in  FIG. 2 , User A has accounts in Bank 1 and Bank 2, and User B has accounts in Bank 2. As shown in  FIG. 2 , each proxy instance includes account credentials and properties. 
     An institution interface module (e.g., one of institution interface modules  131 ,  132 , or  133 ) functions to model the internal interface (e.g., interaction with one of APIs  161 ,  162 , or  163 ) of at least one application (e.g., the application  153 ) with an external institution (e.g., one of institutions  141 ,  142 , or  143 ). An institution interface module may be established for each institution with which the system  100  can interface. For example, an institution interface module may exist for each bank and/or credit card company that is available in the system. The institution interface module may include a set of rules and processes of a particular institution. The institution interface module may include a proxy sub-module that defines how the institution recognizes and/or authenticates a particular application. Some banks may depend on the MAC address of a device (e.g., a MAC address of user devices  171  and/or  172 ), some may depend on asymmetric cryptography tokens, and others may generate encrypted tokens. The proxy sub-module is used in establishing the proxy instance information. The institution interface module can additionally include institution protocol sub-module, which defines a mapping between provided API  110  functionality and the form and mode of communication with the external institution (e.g., institutions  141 ,  142 , or  143 ). The institution protocol sub-module can define the headers, body, and other properties of messages sent to the associated institution. The protocol sub-module may additionally define how data should be processed to form that message. In some cases, the data may be encrypted in a standard or proprietary format, which the protocol sub-module can define. Additionally, the protocol sub-module can define the communication flow to fulfill a request. In some cases, multiple requests may need to be made to complete a request objective. Other aspects of interacting with an interface (e.g., APIs  161 ,  162 , and/or  163 ) of an external institution (e.g., institutions  141 ,  142 , and/or  143 ) may additionally be built into the institution interface module such as multi-factor authentication rules. 
     An institution interface module may be constructed based on use of an actual first-party application (e.g., the application  153 ). For example, communication of, and/or source code of, the first-party application can be parsed and analyzed to establish some or all of an institution interface module. In some implementations, source code of a first-party application (e.g., the application  153 ) of an external institution is parsed and analyzed to establish some or all of an institution interface module for the external institution. In some implementations, communication between an external institution and a first-party application (e.g. the application  153 ) of the external institution is parsed and analyzed to establish some or all of an institution interface module for the external institution. 
       FIG. 3  is a flowchart illustrating an example method of accessing user account data, according to an embodiment. As shown in  FIG. 3 , the method can include creating an application proxy instance (block  310 ), optionally setting up a communication session through the proxy instance (block  320 ), receiving a normalized account request (block  330 ), negotiating communication with an external interface through a proxy instance (block  340 ), and returning results (block  350 ). The method functions to provide programmatic access to one or more external services (e.g., external user account systems of external institutions) that lack exposed programmatic access. The external services may be proprietary and/or non-public. The external services can be provided by external institutions, as described above. Such institutions may have first-party applications that enable users to access user account information via a mobile or desktop application. Such first-party applications may use a proprietary or customized API (e.g., API  161 ,  162 , and/or  163 ) of the external institution. Such APIs are commonly not public and not exposed. For example, a developer is commonly prevented from registering an account and using an open API authentication approach to arbitrarily access the API resources of external institutions. Additionally, such APIs are non-trivial customized interface protocols that are not shared with other institutions, e.g., each institution conforms to its own interface. The method can additionally provide a normalized interface to a plurality of external services (e.g., external institutions  141 ,  142 , and/or  143 ). The method enables a programmatic interface into an account within an institution by leveraging an application proxy approach. A virtualized “image” or digital simulation of an application instance is maintained in the application proxy system  120  and used to access the unexposed API (e.g., API  161 ,  162 , and/or  163 ) of the institution. While the system  100  may be applied to financial institutions, the system  100  may additionally or alternatively be applied to providing API access to any other external entities with closed or limited API access. The method may be implemented through the system  100  as described above, but may alternatively be implemented by any suitable system. 
     At block  310 , which includes creating an application proxy instance (e.g., an application proxy instance  121 ,  122 , and/or  123 ), the system  100  functions to establish a digital image of a first-party application instance (e.g., the application instance  153 ) for a selected institution (e.g., the Bank 2  142 ). Creating an application proxy instances may be initiated in response to receiving an initial request. The initial request may be initiated by a user (or entity) (e.g., User A or User B) interacting with an external user-facing system/application (e.g., application instances  151  and/or  152 , executing on either of user devices  171  or  172  and/or another suitable device, and/or further executing on another system of the application instances  151 ,  152 ) of a customer (e.g., a developer). The external user-facing system/application may then send the initial request to the system  100 . The user (e.g., User A and/or User B) may have a user account with the external institution (e.g., an online bank account). An application proxy instance (e.g., one of proxy instances  121 ,  122 , and/or  123 ) can be created during the initial registration or at a later time, which will provide access to account information of the external institution. Once created, the application proxy instance of that user can be persisted and used at a later time for that given user-institution combination (e.g., “User A-Bank 1”, “User A-Bank 2”, “User B-Bank 2”). However, a new proxy instance may be created when the proxy instance becomes invalid (e.g., as a result of institution API changes, password/login changes made within the institution, and/or other changes to invalidate a proxy instance). The initial request may be received through a normalized API (e.g., API  110 ) as a connection request. The connection request may be accompanied by parameters that specify a selected institution (if there are multiple institution options) and user credentials for the institution. The user credentials may include a username, password, pin code, and/or any suitable credentials. The API request may additionally include authentication credentials such as a client identifier and secret token that is associated with the account in the system. 
     Creating a proxy instance may include negotiating registration of the proxy instance with the institution, which functions to establish the proxy instance with the selected external institution. An institution interface module (e.g., one of the modules  131 ,  132 , or  133 ) may facilitate navigating the communication handshaking during the initial login. Different institutions may have different processes to register or enroll a new application (which in the method is a proxy instance) such as multi-factor authentication. During the negotiation, various elements may be extracted and stored as part of the proxy instance. Similarly, some properties may be generated based on communication with the institution. For example, a MAC address or a unique device identifier may be used in connecting to the services of the external institution. Such properties may be stored as part of the proxy instance. 
     As mentioned above, multifactor authentication (MFA) may be part of negotiating with an external institution. For example, an external institution may respond with indication of a MFA credential requirement. Such MFA requirements may be fulfilled by relaying the MFA challenge/task up to a user. In one implementation, the system  100  receives a message indicating that a security question should be asked to complete the negotiation. The security question is passed back to the associated application (e.g., applications  151  and/or  152 , which may be operated by a customer/developer account of the system  100 ). Then, the associated application may present the security question in some manner to obtain the user response. The MFA can include security questions, additional pin codes (such as those supplied by a one-time password generator or a code transmitted to a secondary device), or any suitable form of MFA. 
     At block  330 , the system receives a normalized account request via the API  110  of the system  100 . As mentioned above, the syntax and mode of communicating an API request is normalized such that the format is independent of the institution. The requests can include a variety of types of requests which may include: obtaining a list of transactions; requesting details on a particular transaction; performing some financial transfer (moving money from savings to checking, setting up transfer to another account, making scheduled payments, digital deposit of a check, and/or the like), updating account information (e.g., updating contact information, changing password, manage alerts, and/or the like), requesting services (e.g., new cards, reporting fraud, and/or the like), and/or the like. A normalized account request may be mapped to an institution interface module (e.g., one of the institution interface modules  131 ,  132 , or  133 ) or other suitable component that defines communication to fulfill the API request. 
     At block  340 , which includes negotiating communication with an external interface (e.g., one of APIs  161 ,  162 , and/or  163 ) through a proxy instance (e.g., one of the proxy instances  121 ,  122 , and/or  123 ), the system  100  functions to execute and manage communication between the system and an external institution system (e.g., one of systems  141 ,  142 , and/or  143 ) when fulfilling an account request. The proxy instance (e.g., one of the proxy instances  121 ,  122 , and/or  123 ) provides a mechanism through which access may be granted. The communication is executed while an authenticated session is active. Communication sessions may be expired by the system  100  or the external institution for various reasons, such as remaining inactive for a set amount of time. A communication session may be active subsequent to enrolling a proxy instance or may require setting up a session through the proxy instance as described below. 
     Negotiating communication may include creating requests that conform to expected messages of the external institution. This can include setting headers, body contents, and other message properties. An institution may expect particular headers. For example, the headers may include a host or path, a data, content type, cookies, MAC address, a user identifier, authorization properties, and/or other suitable headers. Creating requests can additionally include transforming request properties into an expected form, which may include applying a set encryption pattern to a request. In one variation, transforming the request involves encrypting content according to a public key, wherein the public key may be stored as part of the proxy instance. The institutions may take varying approaches to how information is communicated. In an alternative institution, the contents of a message may be unencrypted, in which case, the contents may be submitted in a plaintext, unencrypted form. In addition to creating requests that conform to expected messages of the external institution, the method can include following a request-response pattern. That pattern can involve a single request and response, but may alternatively include a sequence of different request and responses to obtain desired information. 
     In some variations, information or actions may not be available through the first proxy instance and so the method may include automatically switching to a second proxy instance with supported functionality. For example, full bank statements may not be available in a mobile application, and the institution API (e.g., one of APIs  161 ,  162 , and/or  163 ) may not include such functionality. Accordingly, when that functionality is required to fulfill an API request of the API  110 , then a second proxy interface may be used. In some variations, an API request via the API  110  may require multiple institutions to be queried. Such an API request may be particularly useful for summarizing financial statements across multiple accounts. The method can include negotiating communication for multiple institutions and combining results into a combined form. 
     At block  350 , which includes returning results, the system  100  functions to deliver the results as a response to the request. Returning the results includes transforming the data obtained from the external institution into a normalized form. The information is formatted into a standardized format that is substantially similar in representation between different institutions served by the system  100 . Transforming the data can additionally include processing, supplementing, and/or otherwise enhancing information. Some information provided by an institution may be poorly formed. For example, store information for a particular transaction may be poorly labeled and may be represented different from other institutions. Such contextual information about external entities can be cleaned and/or supplemented with additional information. For example, an entity may be supplemented with categorical labels, tags, geolocation information, and/or other suitable information. The returned results can be represented data format such as JSON, XML, or any suitable format. 
     The method can additionally optionally include block  320 , which includes setting up a session through a proxy instance that was previously created, and functions to facilitate accessing information after negotiating a proxy instance for an account and institution. The proxy instance may store and maintain information required for subsequent access. The external institutions may restrict access to set sessions, which may expire after some amount of time or may require reconfirming user credentials. Thus, when an API request for an account occurs after a communication session has expired, then the method may automatically set up a new session using the previous user credentials and proxy instance credentials. In some variations, MFA challenges, such as security questions, may be automatically completed. 
     The method can additionally include re-capturing updated credentials, which functions to update user credentials for an institution. Updated credentials may be updated when a user changes them within the institution or when the proxy instance is otherwise locked out of the account. An error may occur indicating that a communication session was not successful, and then an API request can be submitted to update a proxy instance with new credentials. 
     Referring again to  FIG. 1 , in some implementations external user account system of the external institutions may include public web browser interfaces. For example, as shown in  FIG. 1 , the bank 1 system  141  may include a web browser interface  191  for accessing the bank 1 system  141  via a web browser (or any suitable web client) (e.g., web browser  181  of the user device  173 ). As described herein and further below in reference to  FIGS. 6 and 7 , the system  100  provides access to the user account data via private, proprietary APIs (e.g., API  161 ) of external institutions, as opposed to access via a public web browser interface  191 . In some implementations, the web browser interface  191  is a web server that hosts a web site for access of the external institution system via a web browser over the Internet. 
       FIG. 4A  illustrates aspects of the application proxy system  120 , according to an embodiment. As shown in  FIG. 4A , the application proxy system  120  includes application proxy instances (e.g., proxy instances  421 ,  422 ,  423 ,  424 , and  425 ) for user accounts (e.g., user accounts  411 ,  412  and  413 ) of developer accounts (e.g., Dev Account B  431  and Dev Account A  432 ) at the system  100 . The application proxy system  120  includes an application proxy instance management module  441  that is constructed to generate application proxy instances, configure application proxy instances, remove application proxy instances, and/or the like. 
     In some implementations, each application proxy instance (e.g., proxy instances  421 ,  422 ,  423 ,  424 , and/or  425 ), specifies a developer account, a user account of the developer account, an associated external user account system (e.g., an external institution), and credentials of the user account for the external institution, as shown in  FIG. 4B . In some implementations, each application proxy instance specifies properties of the application proxy instance. In some implementations, properties include one or more of a unique user identifier code, an authentication token, a MAC address (e.g., a MAC address of a user device  171  and/or  172 ), or any suitable information. 
     In some implementations, the application proxy instance management module  441  creates the application proxy instance responsive to a request to create an application proxy instance. In some implementations, the request to create an application proxy instance specifies information identifying an external user account system, and a user account of an external user-facing system/application (e.g., a user account of the external user-facing system/application  152  of  FIG. 1 ). In some implementations, the request to create an application proxy instance specifies user credentials for the external user account system. In some implementations, the request to create an application proxy instance specifies information identifying an account of the system  100  associated with the external user-facing systems/application. In some implementations, the request to create an application proxy instance specifies properties for the application proxy instance. In some implementations, properties for the application proxy instance include at least one of a unique user identifier code, an authentication token, a MAC address, user accounts of the corresponding external user account system, and/or any other suitable information. 
     In some implementations, the application proxy instance management module  441  stores the created application proxy instance in association with a user account (e.g., “User A”  411  of  FIGS. 4A and 4B ) of an external user-facing system/application (e.g., a user account of the external user-facing system/application  152  of  FIG. 1 ). In some implementations, the application proxy instance management module  441  stores the created application proxy instance in association with an account (e.g., “Dev Account B”  431  of  FIGS. 4A and 4B ) of the system  100  associated with an external user-facing system/application (e.g., a user account of the external user-facing system/application  152  of  FIG. 1 ). In some implementations, the application proxy instance management module  441  stores the created application proxy instance (e.g., “Proxy Instance User A Bank 1”  421  of  FIGS. 4A and 4B ) in association with an account (e.g., “Dev Account B”  431 ) of the system  100  associated with an external user-facing systems/application, and a user account (e.g., “User A”  411 ) of the external user-facing systems/application. In some implementations, the application proxy instance management module  441  stores the created application proxy instance in association with an account of the system  100  associated with an external user-facing systems/application, a user account of the external user-facing systems/application, and information identifying the external user account system (e.g., “Bank 1  141 ” of  FIG. 4B ) of the application proxy instance. In some implementations, the application proxy instance management module  441  stores the created application proxy instance in association with an account of the system  100  associated with an external user-facing systems/application, a user account of the external user-facing systems/application, information identifying the external user account system of the application proxy instance, and information identifying user accounts of the application proxy instance. 
     In some implementations, creating the application proxy instance includes controlling the application proxy instance management module  441  to construct the application proxy instance to simulate communication, register, negotiate registration, and/or the like, of an application (e.g., application  153  of  FIG. 1 ) (of the external user account system of the application proxy instance) with the external user account system on behalf of the user account (e.g., “User A”, “User B”) of the application system. 
     Additional examples and details of accessing user account data via proxy instances of the system may be found in the &#39;346 patent. 
     As mentioned above, the system  100  may also be used, via the API  110 , to access various types of user account data, including documents (such as statements). The system  100  may also be used, via the API  110 , to initiate transactions (such as a transfer of funds between accounts, schedule payments, etc.). The system  100  may also be used, via the API  110 , to update account information or request services. Additional examples and details of such functionality of the system is provided below, and may also be found in the &#39;346 patent. 
     IV. Example Systems and Methods for Programmatically Verifying Transactions 
       FIG. 5  is a flowchart illustrating an example method of processing transactions, according to an embodiment. As shown in  FIG. 5 , the method can include acquiring user account (also referred to herein as “institution account”) credentials (block  510 ), receiving a transaction request associated with at least one endpoint (block  520 ), collecting transaction information of the endpoint (block  530 ), and returning a transaction response (block  540 ). In some embodiments, the method can optionally include executing the transaction (block  550 ), which functions to process the transaction between two endpoints. In some embodiments, the method does not perform execution of the transaction, receiving the transaction request functions to initiate the retrieval of transaction addressing information of the at least one endpoint, collecting transaction information of the endpoint includes collecting transaction addressing information of the endpoint, and returning a transaction response functions to transmit the collected transaction addressing information of the endpoint. The method functions to leverage account access during the transaction process. Variations of the method can be used to add functionality such as verifying account information used in financial transfers, programmatically transferring funds, setting programmatic events, catching errors and fraud, performing conditional processing of a transaction, and/or other suitable operations. The method may be performed by the system  100 . In some implementations, the transactions are Automated Clearing House (“ACH”) transactions (e.g., transactions executed via the ACH network), but any suitable type of transaction or transaction network may be used. In some implementations, the transactions are Same Day ACH transactions executed on the ACH network. In a first implementation, the method enables a customer/developer, via the API  110 , to obtain verified ACH endpoint information. For example, an account number and a routing number may be obtained, as well as verification of ownership of the account. In this variation, the system  100  provides the information to execute the transaction. In another embodiment, the method additionally executes the transaction having obtaining the required information and verification. The method of  FIG. 5  may be implemented by the system  100 , but the method may alternatively be implemented by any suitable system. 
       FIG. 6  is a simplified block diagram of the computing system and network environment of  FIG. 1 , according to an embodiment. The method of  FIG. 5  is described below in reference to certain aspects of  FIG. 6  (or, alternatively,  FIG. 1 ) 
     At block  510 , which includes acquiring institution account credentials, the system  100  functions to obtain login information for an institution (e.g., the institution  142 ). The institution account credentials may include a username and password. The account may be an account of an external institution. Additionally, an institution may include additionally authentication challenges such as a pin code, security questions, single-use passwords, secondary device code verification, biometric identification, and/or any suitable form of multi-factor authentication (MFA), as described above. Such additional authentication challenges may be collected at the same time of the account credentials, but the MFA authentication process may alternatively be defined in the API protocol. For example, if the primary account credentials are not sufficient, the MFA challenge may returned in a response, this additional credential request can be repeated as required before access to the account is obtained. The institution account credentials can additionally be stored, and automatically used to complete subsequent access or login attempts. 
     The account credentials may be provided through an API request of a customer/developer or application of the customer/developer to the API  110 . The API  110  may be used in establishing, setting up, or enrolling a new user account. One user may have at least one associated user account at an external institution, but may be linked or associated with multiple user accounts at multiple external institutions. Account credentials may be obtained for each user account. 
     At block  520 , which includes receiving a transaction request associated with at least one endpoint, the system  100  functions to initiate the retrieval of transaction addressing information of an endpoint. The endpoint may be a transaction endpoint, which may be any suitable endpoint from which funds may be withdrawn or deposited. In a common transaction, there is a single withdrawal account and a single deposit account. The method can be used in obtaining information for one or more endpoints. In some variations, there may be a plurality of withdrawal and/or deposit accounts. In one variation, the transaction request is identical to an enroll user request used to obtain the user credentials of block  510 . The account credentials may alternatively be previously obtained or obtained in response to the transaction request. 
     In one variation, in which the transaction request is for information about an account, the API request may specify an institution and account credentials. Additional credentials may additionally be required such as a pin code, state in which an account was created, or MFA challenge answers. A second request with similar parameters may be submitted to obtain the account credentials for other involved transaction endpoints. 
     In another variation, the transaction request may explicitly define the transaction details. The transaction request may include at least one withdrawal account endpoint and deposit account endpoint. Account credentials may be specified for each endpoint. In one variation, a single API request may include account credentials for both endpoints. In another variation, a transaction resource is used, such that withdrawal endpoint information, deposit account information, and transaction details can be specified asynchronous. For example, a transaction resource is created through an API request via API  110 . Later, an API request hits the new transaction resource (by specifying a transaction identifier) to specify withdrawal information, then deposit information, and then the amount to be transferred. Once all the information is populated, the transaction may be executed either automatically, in response to an executed command, or scheduled for a later time. Bulk, aggregate, or group transactions may additionally be specified in a request. If multiple entities are withdrawal endpoints, then the division of funds may be specified (e.g., a percentage breakdown or amount breakdown). Similarly, funds for multiple deposit endpoints may be specified. 
     At block  520 , which includes collecting transaction information of the endpoint, the system  100  functions to access and determine properties of a transaction endpoint. Collecting transaction information of the endpoint may involve using the account credentials to gain account access in an institution. The account access may be facilitated by using a proxy application, as described above. The account access can be used to request and obtain account documents that include endpoint information. The account documents may include bank statements or other suitable documents. If the documents are in PDF or other alternative formats, the content may be scraped to identify transaction information. 
     At block  530 , the system  100  collects transaction information and/or transaction addressing information of the endpoint. The account addressing information may be the account number and the routing number of an account. Billing address, wire routing number, and/or other account information can additionally be pulled. In one variation, the account number and routing number are available in banking statements. An extraction script may be used to pull the document and then isolate the information from the document. Accessing the account number and the routing number in an automated fashion may avoid chances of error. As a first benefit, access to the account provides evidence that the owner of the account participated in providing the transaction endpoint information. As another benefit, the information is automatically pulled, which avoids human error. 
     Collecting transaction information of the endpoint, at block  530 , may additionally include collecting transaction status information of the endpoint, which can include indication of fund requirements, account fraud checks, and other status information. Various stages can be built into providing the transaction information, which provide different safeguards and/or features into financial transactions. 
     In a first optional stage, the transaction status information can determine a sufficient funds status. The sufficient funds status may be applied to a withdrawal account to ensure that the account has funds to complete the transaction. Transaction history and/or current fund value may be accessed through the account access. In one variation, the fund amount is returned in the response such that the customer/developer/application can respond appropriately. In another variation, the transaction amount is compared to available funds. If sufficient funds are not found, then an error or warning may be raised. 
     In another optional stage, the account may be processed for fraud patterns. For example, the age of the account may be accessed. Newly created accounts may be less trustworthy than established accounts with significant history. Similarly transaction history may be assessed for fraudulent behavior. If the account is used for a diverse range of transactions indicative of normal behavior then the account may be identified as normal. If the account only participates in repeated high value transactions or other fraud patterns, then the account may be flagged as fraudulent. Additionally, the entities involved in the transaction may be indicative of fraud. 
     The method may additionally include verifying transaction conditions during one or more stages. Transaction conditions may be used to take any suitable action. The available actions can include permitting a transaction or preventing a transaction. Additionally, the action can include sending a notification. The notification can include an email, text message, a platform message, a phone call, or any suitable notification. The action may additionally include triggering a programmatic event. In one variation the programmatic event is a callback event, wherein an HTTP message is sent to a destination. Conditions may be customized or selected from a set of provided conditions. Example conditions can include a condition that triggers a notification for transactions over a particular amount; a condition based on available funds after the transaction to alert a user to funds below a threshold; and a condition based on the frequency of transactions or the entities involved in the transaction account. Conditions can be scoped for a developer account, a particular institution account, or for any suitable scope of entities. 
     At block  540 , the system  100  returns a transaction response so as to transmit the results of the transaction request. The transaction response is may be made in a synchronous API message from the API  110  that is sent in response to an initial request. Alternatively, a status API resource may be used such that an application/service can periodically check the status API resource to determine the processing status and/or the results. Alternatively, any suitable approach may be used to provide the results to the initial request. 
     In an implementation, the response provides the addressing information used for an endpoint. If there are no errors or warnings with respect to the account, then account information may be NACHA compliant as the endpoint information was accessed and obtained in a manner that validates the ownership of the account (e.g., by providing credentials and optionally multi-factor authentication responses). The transaction response can include the account number, the routing number, and/or any additional information for the endpoint that is used in executing the transaction. The transaction response may additionally include the available funds, such that the requesting entity can check for sufficient funds. The response may additionally indicate if sufficient funds are available if the transaction amount was provided, which functions to hide the available funds from the requesting entity while preventing overdraft transaction. The transaction response can additionally include other fields such as a status field, where the account may be labeled according to any categorization of the account. For example, the status may indicate that the account is normal or fraudulent. 
     Additionally or alternatively, the method can include optional block  550 . At block  550  the system  100  executes the transaction, which functions to process the transaction between two endpoints. In this variation a request to execute a transaction between at least two endpoints is received. Additionally, returning a transaction response may include returning results of the transaction in the response. In another implementation, the method includes executing the transaction. The transaction response can include information about the status of the transaction when the transaction is submitted, being processed, and/or completed. Transactions may not be instantaneous, and as such the initial transaction response may indicate if the transaction was successfully initiated. Successfully initiated means that the transaction endpoint information was successfully retrieved, that any conditional stages (such as a sufficient funds stage, a fraud-check stage, and custom conditions) are satisfied. A subsequent response or status resource may be updated that reflects the status of the transaction. A transaction resource may be updated with a pending process, when the transaction is initiated and proceeding normally. The transaction resource can be updated with a completed status possibly indicating the time of completion. If an error or issue is encountered, the status of the transaction resource may be updated to reflect the error or issue. The method may additionally include monitoring status of transaction and triggering programmatic event according to the status. 
     In one variation, executing the transaction can include establishing proxy accounts in at least two institutions, and expediting transactions between the two institutions through an internal deposit to a first proxy account in a first institution and a second internal deposit from a second proxy account in the second institution. In some cases, transactions between institutions are slower than transactions made within an institution. By establishing a cross institution account network, transactions can be facilitated between two accounts in different institutions with similar speeds of internal transactions. The proxy accounts may include a funds reserve, which may be periodically balanced between proxy accounts to maintain an operational reserve of funds. 
     Additionally, the method may be applied to create an abstraction between a user and the underlying account. A transaction endpoint can be abstracted to a user entity, which may be associated with multiple optional transactional endpoints (e.g., different bank accounts). Accordingly, the method may include selecting an institution, which functions to dynamically select a connected account to participate in a transaction. Various conditions may be set to respond to events when receiving a transaction request, collecting information for the transaction, and/or executing a transaction. In one variation, one institution is set as a primary account and another account managed by the same entity is set as a secondary account. If the primary account is not able to complete a transaction, the method may detect an error condition and automatically fails over to the secondary account. In another variation, a set of accounts may be preconfigured to be used depending on properties of the request. In combination with the proxy transfer endpoint, the identifying information for the proxy endpoint can be used, but the underlying service automatically will use an automatically selected account to use for the funds. For example, a set of entities and/or category of entities/transactions may be set to use particular accounts. Similarly, transactions to one proxy account may be automatically split into transactions with multiple associated accounts. For example, an account holder may set a proxy account to automatically split deposits between two accounts in a 30/70 balance. 
     Referring now to  FIG. 6 , the system  100  functions to provide an interface (e.g., via the API  110 ) for applications and services that can facilitate the process of transferring funds. The system  100  can function to provide verified account information used in ACH transfers, to execute transfer of funds, to enable programmatic events during transfer process, to mitigate risk and errors, and/or provide alternative transaction functionality. As described above in reference to  FIG. 1 , the system  100  is part of a larger API platform, which provides an API to access account data and execute transactions, among other items. In some variations, the system  100  is part of a multi-tenant API platform that enables a plurality of developers to create accounts and build applications and/or services that leverage the API of the API platform. In alternative variations, the system  100  is part of a single-tenant API platform and may provide an internal API for a dedicated set of products or services. For example, a product may be built on top of the API platform that enables end users to create accounts to manage accounts with one or more institutions (e.g., banks, credit card companies, investment managers, etc.). 
     The API  110  functions to provide an interface for accessing institution transaction endpoint information. The API  110  can additionally provide a normalized customer facing interface. In one implementation, the API  110  leverages an application proxy instance  121 , which simulates a proprietary first-party application accessing a closed API of an institution (e.g., the institution  142 ). The system  100  can include additional components or services that particularly facilitate the access of information relating to a transaction endpoint. For example, a service, script, or module can be configured to access statements or other suitable documents that can contain endpoint information such as account number and routing number information. The statements or information may be contained in pdf or other suitable document formats. The system  100  can include document readers that can access and extract the requested information from the statements. 
     In one variation, the API  110  allows an API request to specify an account, and a response output provides the information related to executing a transaction with the endpoint. In one implementation, the API  110  can include at least one API resource for interacting with the transaction endpoint. As shown in  FIG. 7 , an endpoint information request can include institution credentials of an account. The credentials can include username and password. The API protocol can additionally provide a mechanism for completing multi-factor authentication challenges such as security questions, or code-based multi-factor authentication. The API request may additionally include other properties such as developer account identifiers, API authentication tokens, institution type identifiers, and other suitable parameters. The response is a data object that includes at least automatically obtained information such as tracking number, routing number, and/or wire routing number. Additional response information can include funds amount (or alternatively a Boolean indicator if the funds are sufficient), an account status (e.g., is the account fraudulent, trusted, etc.), billing address of the account, name of the institution, type of account (e.g., saving, depository, etc.), and other suitable properties. Other API properties or features can include a mechanism to specify if endpoint information is requested or if the transaction should be executed. 
     The institution interface module  132  functions to model the internal interface of at least one first-party application with an external institution (e.g., institution  142 ). The account credentials of a user account (and optionally multi-factor authentication credentials) can be used for an application proxy to gain access to an institution through the institution interface module. The system  100  may additionally include a transaction engine  193 , which can facilitate the transfer of funds between two accounts. The transaction engine  193  can be integrated with the API  110 , such that an API request can direct the execution of a transaction. The transaction engine  193  can execute ACH transactions, but may alternatively or additionally use other financial tools to withdrawal funds and/or deposit funds. With a transaction engine, transactions can be executed between two accounts that have been configured with account credentials. The API response may include the status of the transaction, transaction errors, a status URI or any suitable response to facilitate executing a transaction as shown in  FIG. 8 . In one variation, proxy accounts can be used in different institutions. With sufficient reserves, transfers between institutions can be expedited by transferring funds to and from the proxy accounts, and then asynchronously updating the proxy accounts. 
     The system  100  can also include, in some implementations, a token generation engine  195  (which can manage token generation, as described herein), a permissioning module  196  (which can manage permissioning functionality, as described herein), and an institution transfer module  197  (which can manage transfer functionality, as described herein). 
     The system  100  can additionally include other aspects such as a messaging/notification system, which can manage alerts and/or triggering programmatic events (e.g., callbacks), an engine for generating user interfaces and/or user interface data, and/or the like. The system  100  may additionally or alternatively include any other suitable components to implement the functionality of described in the present disclosure. 
     In some implementations, the system  100  includes a document processing engine  194 . In some implementations, the document processing engine  194  is constructed to process account documents (e.g., account documents  192 ) of an external user account system (e.g., bank system  142 ) of an external institution. The account documents may be processed to identify, extract, and/or obtain transaction and/or account information. In some implementations, in a case where the documents are in a PDF format, the document processing engine  194  is constructed to scrape content of the PDF documents to identify and extract the transaction and/or account information. In some implementations, the document processing engine  194  is an extraction script that is constructed to pull the document and then isolate the transaction/account information from the document (e.g., as described above in reference to  FIG. 5 ). In some implementations, the system  100  accesses the document, stores the accessed document (e.g., in a memory or other storage medium of the system  100 ), and then controls the document processing engine to process the stored document to identify the transaction/account information. Alternatively, or in addition, such document processing may be performed on webpages or other sources of transaction/account information. 
       FIGS. 9-10  are flowcharts illustrating example methods of processing transactions, according to various embodiments. The methods of  FIGS. 5-6  are described below in reference to certain aspects of  FIG. 1  (or, alternatively,  FIG. 6 ). 
     Referring to  FIG. 9 , a method for processing a normalized API request at the system  100  includes: receiving a normalized API request associated with at least one account endpoint, the normalized API request being provided by an external user-facing system/application (e.g., system/application  152  of  FIG. 1 ) by using API  110  of the system  100 , the normalized API request specifying account credentials of each account endpoint of the normalized API request (block  910 ). 
     Responsive to the normalized API request: transaction information of each account endpoint of the normalized API request is collected by using an application proxy instance (e.g., one of proxy instances  121 ,  122 , and/or  123  of  FIG. 1 ) associated with the account endpoint to collect the transaction information from a corresponding institution system (e.g., an external user account system  141 ,  142 , and/or  143  of  FIG. 1 ) by using the associated account credentials specified by the normalized API request and a proprietary API) (e.g., one of APIs  161 ,  162 , and/or  163  of  FIG. 1 ) of the system  100  (block  920 ). 
     Further, a normalized API response is provided to the external user-facing system/application (block  930 ). The normalized API response provides the transaction information of each account endpoint of the normalized API request. Each application proxy instance is constructed to simulate an application of the corresponding external institution system. 
     In some implementations, the collected transaction information for each account endpoint includes at least an account number and a corresponding routing number for use in ACH transactions. In some implementations, the transaction information is collected by processing at least one statement accessed from the corresponding external institution system. 
     Additional examples and details of obtaining transaction and account information via proxy instances of the system may be found in the &#39;023 patent. 
     Referring to  FIG. 10 , a method for processing a normalized API request at the system  100  includes: receiving a normalized API request associated with at least one account endpoint (block  1010 ). The normalized API request is provided by an external application system by using a platform API of the platform system. The normalized API request specifies a transaction and at least one of an account token and account credentials of each account endpoint of the normalized API request. 
     Responsive to the normalized API request, transaction information of each account endpoint of the normalized API request is collected (block  1020 ). The transaction information is collected by using an application proxy instance associated with the account endpoint to collect the transaction information from a corresponding institution system by using at least one of an associated account token and associated account credentials specified by the normalized API request and by using a proprietary API of the institution system. 
     The transaction specified by the normalized API request is executed by using the collected transaction information (block  1030 ). A normalized API response is provided to the external system (block  1040 ). The normalized API response provides results of the transaction. Each application proxy instance is constructed to simulate an application of the corresponding external institution system. 
     In some implementations, the collected transaction information for each account endpoint includes at least an account number and a corresponding routing number for use in ACH transactions. 
     In some implementations, the transaction information is collected by processing at least one statement accessed from the corresponding external institution system. 
     In some implementations, the transaction information (and/or any other account-related information) is collected via one or more of: an application proxy instance, screen scraping (e.g., of a webpage of the institution), an API request to an API of the institution (e.g., that the system is authorized to access), or any combination of these methods. 
     Additional examples and details of such functionality of the system may be found in the &#39;023 patent. 
     In some implementations, the user information of the normalized API request includes a user account identifier for each user account of the external user-facing system/application (e.g., the external user-facing system/application  152 ) corresponding to the normalized API request. 
     In some implementations, the normalized API request includes parameters as shown in Table 1. 
     
       
         
           
               
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 NORMALIZED API 
                   
               
               
                 REQUEST PARAMETER 
                 DESCRIPTION 
               
               
                   
               
             
            
               
                 &lt;Platform Account ID&gt; 
                 An account of an external user-facing 
               
               
                   
                 system/application (e.g., “Dev Account 
               
               
                   
                 A”, “Dev Account B” of FIGS. 1 and 4A- 
               
               
                   
                 4B). 
               
               
                 &lt;User Account Identifier&gt; 
                 An identifier that identifies a user account 
               
               
                   
                 of the application system identified by the 
               
               
                   
                 &lt;Platform Account ID&gt; parameter. 
               
               
                 &lt;Institution ID&gt; 
                 An identifier that identifies an external 
               
               
                   
                 institution system (e.g., institutions 141, 
               
               
                   
                 142, and/or 143). 
               
               
                   
               
            
           
         
       
     
     In some implementations, the &lt;User Account Identifier&gt; is used to select at least one corresponding application proxy instance, and each selected application proxy instance includes user credentials (e.g., as depicted in  FIG. 4B ) to access the associated institution system. 
     In some implementations, the system  100  determines an application proxy instance associated with the normalized API request based on the &lt;Platform Account ID&gt; parameter, the &lt;User Account Identifier&gt; parameter, and the &lt;Institution ID&gt; parameter. In some implementations, the system  100  identifies an application proxy instance of the application proxy system  120  that is managed in association with the &lt;Platform Account ID&gt; parameter, the &lt;User Account Identifier&gt; parameter, and the &lt;Institution ID&gt; parameter, and uses the identified application proxy instance to collect the transaction information. 
     In some implementations, each proprietary API request includes parameters as shown in Table 2. 
     
       
         
           
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 PROPRIETARY API 
                   
               
               
                 REQUEST PARAMETER 
                 DESCRIPTION 
               
               
                   
               
             
            
               
                 &lt;User Credentials&gt; 
                 The user credentials of the 
               
               
                   
                 corresponding normalized API request. 
               
               
                   
                 The user credentials are specified by the 
               
               
                   
                 application proxy instance, e.g., 421-425, 
               
               
                   
                 (e.g., as shown in FIG. 4B) used to 
               
               
                   
                 provide the proprietary API request. 
               
               
                   
               
            
           
         
       
     
     In various other implementations, the normalized API requests and/or the proprietary API requests may include other sets of parameters, depending on the specifics of the APIs and the types of requests involved. For example, other requests may include identifier tokens, multiple account identifiers (e.g., when requesting transfer of funds), etc. Additional examples and details of such other types of requests and functionality of the system may be found in the &#39;023 patent. 
     In some implementations, the system may send various types of alerts and/or other indications to a user device (e.g., user devices  171 ,  172 , and/or  173 ). These various types of alerts and/or other indications may activate one or more applications (e.g., an SMS (simple message service) and/or MMS (multimedia messaging service) process and/or application, an email process and/or application, a process and/or application related to the system, a first-party and/or third-party process and/or application (e.g., of an institution and/or a user-facing application/service), and/or the like) on the user device. For example, as described herein, alerts may be communicated with the user device for the purpose of completing a multi-factor authentication process. In such an example, an SMS message with a secret/authentication code may be communicated to the user device, activating an SMS process and/or application (and/or another process and/or application) on the user device. Such an alert may be sent by the system and/or an institution system. In another example, the system may send alerts to the user device regarding access to a user account of the user, a transaction, and/or the like. Such alerts may notify the user that a new transaction has posted to their account, that a transaction has posted for a particular amount, a transaction has been denied, and/or the like. Such alerts may comprise SMS messages, email messages, and/or other types of messages that may activate various processes and/or applications, as described above. In yet another example, the system may send an alert to the user device including an account document, which may cause a process and/or application suitable for reading the account document to be activated on the user device. In various implementations, alerts may be provided via a permissions plug-in (as described below), and alerts may be provided associated with one or more authorization mechanisms (as also described below). 
     V. System Architecture 
       FIG. 11  is an architecture diagram of the system  100  according to an implementation in which the system is implemented by a server device. Alternatively, the system may be implemented by a plurality of devices, in a hosted computing environment (e.g., in a cloud server), and/or in any other suitable environment. 
     The bus  1102  interfaces with the processors  1101 A- 1101 N, the main memory (e.g., a random access memory (RAM))  1122 , a read only memory (ROM)  1104 , a computer readable storage medium  1105  (e.g., a non-transitory computer readable storage medium), a display device  1107 , a user input device  1108 , and a network device  1111 . 
     The processors  1101 A- 1101 N may take many forms, such as ARM processors, X86 processors, and/or the like. 
     In some implementations, the system includes at least one of a central processing unit (processor) and a multi-processor unit (MPU). 
     The processors  1101 A- 1101 N and the main memory  1122  form a processing unit  1199 . In some embodiments, the processing unit includes one or more processors communicatively coupled to one or more of a RAM, ROM, and computer readable storage medium; the one or more processors of the processing unit receive instructions stored by the one or more of a RAM, ROM, and computer readable storage medium via a bus; and the one or more processors execute the received instructions. In some embodiments, the processing unit is an ASIC (Application-Specific Integrated Circuit). In some embodiments, the processing unit is a SoC (System-on-Chip). In some embodiments, the processing unit includes one or more of an API, an application proxy system, one or more instance interface modules, account documents, a transaction engine, a document processing engine, and/or any other functionality or aspects of the system as described herein. 
     The network adapter device  1111  provides one or more wired or wireless interfaces for exchanging data and commands between the system and other devices, such as external user account systems (e.g., institutions  141 ,  142 , and/or  143 ), external user-facing systems/applications (e.g., applications  151  and/or  152 ), user devices (e.g., user devices  171  and/or  172 ), and/or the like. Such wired and wireless interfaces include, for example, a universal serial bus (USB) interface, Bluetooth interface, Wi-Fi interface, Ethernet interface, near field communication (NFC) interface, and/or the like. In some embodiments, the system communicates with other devices via the Internet. 
     Machine-executable instructions (e.g., computer readable program instructions) in software programs (such as an operating system, application programs, and device drivers) are loaded into the memory  1122  (of the processing unit  1199 ) from the processor-readable storage medium  1105 , the ROM  1104  or any other storage location. During execution of these software programs, the respective machine-executable instructions are accessed by at least one of processors  1101 A- 1101 N (of the processing unit  1199 ) via the bus  1102 , and then executed by at least one of processors  1101 A- 1101 N. Data used by the software programs are also stored in the memory  1122 , and such data is accessed by at least one of processors  1101 A- 1101 N during execution of the machine-executable instructions of the software programs. The processor-readable storage medium  1105  includes an operating system  1112 , software programs/applications  1113 , device drivers  1114 , the API  110 , the application proxy system  120 , the institution interface modules  131 ,  132 , and  133 , and account documents  192 . In some implementations, the processor-readable storage medium  1105  includes the transaction engine  193 , the document processing engine  194 , the token generation engine  195 , the permissioning module  196 , and the institution transfer module  197 . 
     Further details regarding the system architecture are described below. 
     VI. Example Network Environment of the System when Implementing Authorization Mechanisms 
       FIG. 12A  illustrates an example network environment  1200  in which a permissions management system  1204  may operate, according to an embodiment. As shown, the network environment includes the permissions management system  1204 , an external user account system  1206 , an external user-facing system/application  1208 , a permissions plug-in  1210 , a permissions plug-in  1211 , a trusted third-party processor system  1212 , a user computing device  1214 , and a user  1216 . The various aspects of the network environment  1200  may communicate via a network/Internet  1202 . The network/Internet  1202  may comprise a wired and/or wireless network, and/or in certain embodiments may comprise one or more wired and/or wireless network. The various components of the network environment  1200  may communicate via the network/Internet  1202 , and/or alternatively may communicate directly with one another via one or more other wired or wireless connections. In some embodiments, the permissions management system  1204  may include the functionality of the system  100  described above, and/or the functionality of the system  100  described above may be implemented in one or more other computing systems in the network environment  1200 . For clarity of description, however, the following description assumes that the permissions management system  1204  includes the functionality of the system  100  described above. 
     Additionally, the external user account system  1206  may comprise a system of an institution (e.g., one of institution systems  141 ,  142 , and/or  143 ), and while more than one the external user account system  1206  may be involved in communication with the permissions management system  1204 , one external user account system  1206  is shown in  FIG. 12A  for purposes of clarity. 
     Further, external user-facing system/application  1208  may comprise the system and/or application, merchant, and/or the like, with which the user may interact. For example, the user  1216  may interact with the external user-facing system/application  1208  via the user computing device  1214 . In one example, the external user-facing system/application  1208  may comprise an app, and/or web-based application, running on and/or rendered by the user computing device  1214  (e.g., a mobile device, and/or the like), as described above (e.g., in reference to app  151  and/or  152 ). 
     In an embodiment, the external user-facing system/application  1208  may include the permissions plug-in  1210 . The permissions plug-in  1210  may comprise a software/code module, snippet, and/or the like, which may be integrated into the external user-facing system/application  1208 . The permissions plug-in  1210  may be provided by the permissions management system  1204  and/or the external user account system  1206  such that the external user-facing system/application  1208  may include functionality provided by the permissions management system  1204  (either directly or indirectly via the external user account system  1206 ). In one implementation, the permissions plug-in  1210  comprises JavaScript code (or code written in any other programming language) integrated into the external user-facing system/application  1208 . The JavaScript code, when executed, may communicate with the permissions management system  1204  and/or the external user account system  1206  to provide certain functionality as described herein. Advantageously, in some implementations, the permissions plug-in  1210  may generate interactive user interfaces that may be presented to the user  1216 . Information may be obtained from the user  1216  via the interactive user interfaces of the permissions plug-in  1210  (e.g., account credentials, and/or the like). The permissions plug-in  1210  may obtain such information, and communicate the information to the permissions management system  1204  and/or the external user account system  1206  in a secure manner such that the external user-facing system/application  1208  does not have access to the information provided by the user  1216 . 
     Further, the permissions plug-in  1210  may advantageously handle establishing secure communications with the permissions management system  1204  and/or the external user account system  1206 , and/or other functionality as described herein, such that a developer of the external user-facing system/application  1208  need not be concerned with these aspects (thus speeding development of the external user-facing system/application  1208 ). 
     In an embodiment, the user computer device  1214  may include the permissions plug-in  1211  that functions similarly to the permission plug-in  1210  described above. Similar to the permissions plug-in  1210 , the permissions plug-in  1211  may comprise a software/code module, snippet, and/or the like. The permissions plug-in  1211  may be integrated into another software application executed by the user computing device  1214  (e.g., a software application dedicated to enabling communications with, e.g., the external user account system  1206 ) or may otherwise be executable by the user computing device  1214  (e.g., by a web browser of the user computing device  1214 ). The permissions plug-in  1211  may be provided by the permissions management system  1204  and/or the external user account system  1206  such that the user computing device  1214  may include functionality provided by the permissions management system  1204  (either directly or indirectly via the external user account system  1206 ). In one implementation, the permissions plug-in  1211  comprises JavaScript code or code written in any other programming language. The JavaScript code, when executed, may communicate with the permissions management system  1204  and/or the external user account system  1206  to provide certain functionality as described herein. Advantageously, in some implementations, the permissions plug-in  1211  may generate interactive user interfaces that may be presented to the user  1216 . Information may be obtained from the user  1216  via the interactive user interfaces of the permissions plug-in  1211  (e.g., account credentials, and/or the like). The permissions plug-in  1211  may obtain such information, and communicate the information to the permissions management system  1204  and/or the external user account system  1206  in a secure manner such that the external user-facing system/application  1208  does not have access to the information provided by the user  1216 . Further, the permissions plug-in  1211  may advantageously handle establishing secure communications with the permissions management system  1204  and/or the external user account system  1206 , and/or other functionality as described herein, such that a developer of the external user-facing system/application  1208  need not be concerned with these aspects (thus speeding development of the external user-facing system/application  1208 ). 
     VII. Example Systems and Interactions for Authorization Mechanisms 
       FIG. 12B  is a block diagram illustrating example interactions among the aspects of the network environment  1200 , according to various embodiments. As described herein, interactions among the various aspects of the network environment  1200  may enable securely authorizing access to user accounts and user account data (e.g., of the external user account system  1206 , or of multiple external user account systems), and/or securely authorizing initiation or execution of transactions related to the user accounts, via one or more application programming interfaces (“APIs”) and/or one or more authorization mechanisms. Further, interactions among the various aspects of the network environment  1200  may enable a user to revoke authorization to access their accounts. 
     In the diagrams of  FIGS. 12A-12B , and other diagrams described herein, in various implementations the interactions shown and described may be performed in orders different from those shown. For example, certain interactions may take place before or after other interactions, according to various implementations. 
     Interaction among the aspects of the network environment  1200  may be accomplished via various API calls (e.g., through API  110 ), as generally described above. Thus, for example, account credentials, account identifiers, user information, token identifiers, transaction requests, and/or any other information transmitted during the interactions described below may be communicated via normalized API requests. As described above, the API of the permissions management system  1204  may advantageously be clearly defined such that software applications and/or systems may be efficiently developed to interact with the permissions management system  1204  in an efficient manner. Additionally, each communication among aspects of the network environment  1200  may include multiple requests and/or acknowledgments in order to ensure effective communication. Further, communications may be made via secure connections. 
     Referring now to  FIG. 12B , as described above, the permissions management system  1204  includes API service  110  and one or more institution interface modules  132 . The institution interface modules  132  may be in communication with one or more external user account systems, e.g., institution  1240  and/or institution  1245 . The communication between the institution interface modules  132  and the one or more external user account systems may be though various APIs of the external user account systems, e.g., an API  1260 , or some other defined institution interface useable for programmatically communication user account information and/or other information. The system  1204  may, via API  110 , be in communication with an external user-facing system/application, e.g., application  1251  executing on a user computing device  1214 . The system  1204  may also, or alternatively, via API  110 , be in communication with an external user-facing system/application  1250  which may be in further communication with one or more user computing devices, e.g., user computing device(s)  1271 . 
     The system  1204 , as described herein, may include a permissioning module  196  and one or more institution transfer modules  197 . The permissioning module  196  may provide functionality and/or communications related to the one or more authorization mechanisms described herein, including fallback functionality. The institution transfer module(s)  197  may provide functionality and/or communications related to initiating and/or executing transactions related to user accounts, as described herein. As with the institution interface modules  132 , the institution transfer modules  197  may be in communication with one or more external user account systems, e.g., institution  1240  and/or institution  1245 . The institution transfer modules  197  may include some or all of the functionality of the institution interface modules  132  described above, enabling communications with various external user account systems. In some implementations, the institution transfer modules  197  are combined with the respective institution interface modules  132 . In some implementations, the institution transfer modules  197  differ from the institution interface modules  132 , and provide transaction functionality via other APIs or mechanisms suitable for accomplishing the functionality of the present disclosure. 
     The external user-facing system/applications  1250  and  1251  may respectively include the permissions plug-ins  1280  and  1281 , which permissions plug-ins provide functionality as described above in reference to permissions plug-ins  1210  and  1211  of  FIG. 12A , and as further described herein. 
     In addition to the detailed description of the functionality provided herein, additional examples and details are provided in the &#39;500 Publication. Various aspects of the embodiments described in the &#39;500 Publication may be applied to the disclosure of this description in various combinations. For example, the permissions plug-in of the present description may incorporate functionality described in reference to the permissions plug-ins  1210  and  1211  described in the &#39;500 Publication. As another example, the system  100  (including system  1204 ) of the present description may further include components and/or functionality the same as, or similar to, the computing system  100 / 1204  described in the &#39;500 Publication. As yet another example, the methods, user interfaces, interactions, etc. described in the present description may be an addition to, combined with, or replace portion of, the various methods, user interfaces, interactions, etc. described in the &#39;500 Publication including, for example, the user interfaces and associated functionality described in reference to  FIGS. 19A-19J and 20A-20C  of the &#39;500 Publication. 
     As noted above, the system  1204  also includes the institution transfer module  197 , which module may be in communication with an external user account system  1245  through an API  1265  or some other defined institution interface useable for programmatically initiating a transaction with other external user account systems, e.g., institution  1240 . In some implementations, the institution  1245  comprises an external transfer system, e.g., some institution that provides for initiation and/or execution of transactions or transfers. Such an external transfer system may, for example, not specifically store user accounts, but may be dedicated to transaction processing. In some implementation, the institution  1245  may comprise a trusted third-party processor system (e.g., system  1212 ), and/or other suitable system/institution, or some combination of systems/institutions. 
     The transaction is typically facilitated by a transaction network  1290 . For example, and without limitation, the transaction network could be a payments network, such as the Automated Clearing House (“ACH”) network for transactions in the United States. In some implementations, the transactions are Same Day ACH transactions executed on the ACH network. The institution transfer module  197  allows the system  1204  to initiate a transaction with a user account of the external user account system  1240 , typically by identifying the user account using one or more account identifiers, such as an account number and routing number. The transaction typically includes metadata (also referred to herein as “authorization parameters”) such as a transaction types, transaction descriptions, transaction amounts, transaction identifiers, and/or other transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). The transaction type (which may also be referred to as “transfer type”) typically includes variants such as a credit transaction, where the user account is incremented by some specified value, or a debit transaction, where the user account is decremented by some specified value. 
     As described above, the system, related functionality, and related interactions enable securely authorizing access to user accounts, and/or securely authorizing initiation or execution of transactions related to user accounts, via the various APIs and/or one or more authorization mechanisms. Such access may include access to user account data associated with the user accounts. Such transactions may include, e.g., an electronic payments, or the like. Such APIs may include public and/or non-public (e.g., proprietary) APIs. Advantageously, such one or more authorization mechanisms may include, e.g., a primary authorization mechanism, and one or more fallback authorization mechanisms. 
       FIG. 13  is a flowchart illustrating certain aspects of the one or more authorization mechanisms, according to an embodiment. For example, the operations of  FIG. 13  may be performed by the permissioning module  196  (and/or one or more additional aspects of the permissions management system  1204 ), in coordination with one or more of the permissions plug-ins  1280  and/or  1281  of  FIG. 12B . Additionally, in various embodiments, and as described herein, certain blocks of the flowchart may be omitted, or ordered differently, or additional blocks may be added. 
     At block  1310 , the permissions plug-in requests a user to select an institution using some user interface. The permissions plugin-in passes the selection of a particular institution to the permissions management system  1204 . The permissions management system  1204  performs a lookup within the system to determine what authorization mechanisms are supported by that particular institution. Such information may be stored in a database of the permissions management system  1204 , and may include information indicating which institutions support which of a plurality of possible authorization mechanisms, including, e.g., the primary authorization mechanism and/or one or more of the fallback authorization mechanisms. 
     a. Example Primary Authorization Mechanism 
     At block  1320 , a determination is made whether the institution supports the primary authorization mechanism. For example, and without limitation, the institution could support credential-based access mechanisms to the user&#39;s account on the external user account system. Where the institution supports the primary authorization mechanism, the system can use the primary authorization mechanism at block  1330 . 
     According to an implementation, where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), and where an external user account system associated with the user account provides support for a primary authorization mechanism, the system may use the primary authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The primary authorization mechanism may include the system obtaining the account credentials from the user, and generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, depending on the external user account system associated with the user account, the primary authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The primary authorization mechanism may include the system automatically accessing institution and/or account identifiers associated with the user account (e.g., a routing number and an account number associated with the user account) via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the primary authorization mechanism, automatic access of the institution and/or account identifiers, combined with the user-provided account credentials, may authorize the system to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Note that if there is a failure in primary authorization mechanism, at block  1340 , the system can commence the first fallback authorization mechanism as depicted in  FIG. 13 . For example, where a credential-based authorization flow is utilized and the user enters incorrect account credentials (or when the user declines to enter credentials), the system can commence the first fallback authorization mechanism flow in the permissioning plug-in. 
     Assuming there is no failure in the primary authorization mechanism (e.g., at block  1340 ), at block  1350 , in one embodiment, the system can generate a token associated with the user account. In some implementations, such a token may be useable by the system for certain types of further authorizations, or in a manner similar to the “token” described herein and in the &#39;500 Publication. 
     b. Example First Fallback Authorization Mechanism 
     Where the institution is determined to not support the primary authorization mechanism, or where the institution is not recognized by the permissions management system  1204 , or where the first authorization mechanism fails as indicated at block  1304  one or more fallback authorization mechanisms may be utilized. 
     For example, according to an implementation, where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism (or the primary authorization mechanism fails), the system may automatically use a first fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The first fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. As with the primary authorization mechanism, the first fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism, depending on the external user account system associated with the user account, the first fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The first fallback authorization mechanism may include the system automatically accessing institution and/or account identifiers associated with the user account via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the first fallback authorization mechanism, the system may compare the automatically accessed institution and/or account identifiers with the account identifiers obtained from the user. If the institution and/or account identifiers match, the institution and/or account identifiers are thereby verified and the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Thus, returning to  FIG. 13 , if the institution does not support the primary authorization mechanism, or there is some failure in the process of the primary authorization mechanism, the permissions management system  1204  may be configured to cause the permissions plug-in to request information in support of initiating the one or more fallback authorization mechanisms. For example, at block  1360 , a request is made of the user for an institution identifier, such as a routing number. This operation can be skipped where the permissions management system  1204  already has access to the correct institution identifier or can perform an independent lookup for the correct institution identifier. Alternatively, the user can be requested to confirm the institution identifier, which is displayed to the user in an interactive user interface. An example interactive user interface for block  1360  is illustrated by  FIG. 14A , according to one embodiment. In  FIG. 14A , the user is asked to provide the institution identifier, represented as a numerical routing number in  FIG. 14A . At block  1370 , a request is made of the user for the user&#39;s account identifier, such as an account number.  FIG. 14B  illustrates an example user interface used with the processing of block  1370 , according to one embodiment. As depicted in  FIG. 14B , the user may be asked to confirm the accuracy of the account number by requiring the user to enter the number twice and performing a validation check that the two numbers match. The check may be performed by the permissions plug-in or the permissions management system. At block  1371 , as described above, the first fallback authorization mechanism may include the system automatically accessing institution and/or account identifiers associated with the user account via the simulated instance(s) of software application(s) and/or APIs of the external user account system. Such institution and/or account identifiers may be accessed via documents of the user account, or via another suitable mechanism. Under the first fallback authorization mechanism, the system may compare the automatically accessed institution and/or account identifiers with the account identifiers obtained from the user. If the institution and/or account identifiers match, the institution and/or account identifiers are thereby verified and the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. 
     c. Example Second Fallback Authorization Mechanism 
     At block  1371 , where the institution is determined to not support the primary authorization mechanism or the first fallback authorization mechanism, or where the institution and/or account identifiers cannot be found for matching, or they do not match, the permissions management system  1204  may proceed with operations associated with a second fallback authorization mechanism. 
     For example, according to an implementation, where a user can provide account credentials associated with a user account (e.g., a username and a password associated with the user account), but where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first fallback authorization mechanism (or the primary authorization mechanism and/or the first fallback authorization mechanism fail), the system may automatically use a second fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The second fallback authorization mechanism may include the system obtaining, in addition to account credentials associated with a user account, account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The second fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account. As with the primary authorization mechanism and the first fallback authorization mechanism, the second fallback authorization mechanism may include the system generating or instantiating one or more proxy, virtualized, or simulated instances of one or more software applications that are configured to interface with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. Alternatively, as with the primary authorization mechanism and the first fallback authorization mechanism, depending on the external user account system associated with the user account, the second fallback authorization mechanism may include the system interfacing directly with computing systems of the external user account system via public or non-public (e.g., proprietary) APIs of the external user account system, using the account credentials, as described herein. The second fallback authorization mechanism may include the system automatically accessing user account data of the user account, via the simulated instance(s) of software application(s) and/or APIs of the external user account system, to automatically verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) shown in the user account match the amounts of the deposit(s) initiated by the system). The one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user account data) related to the authorization transactions, such as transaction types (e.g., credit transaction, debit transaction, and/or the like), transaction descriptions, transaction amounts, transaction identifiers, and/or other transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the second fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., the simulated instances of software applications and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Thus, returning to  FIG. 13 , if the institution does not support the primary authorization mechanism or the first fallback authorization mechanism, or there is some failure in the operations of the primary and first fallback authorization mechanisms, at block  1380  the system proceeds to initiate one or more authorization transactions with the identified institution. In some implementations, the transactions are Same Day ACH transactions executed on the ACH network. The system, in one embodiment, can use the institution transfer module  197  to make a call to an API at another institution which proceeds to initiate the transaction through the transaction network. Alternatively, where the system has a direct connection to the transaction network, the system can initiate the transaction through the transaction network without the need for an intermediary institution. 
     At block  1390 , in one embodiment, the system can generate an interim token associated with the user account while the system awaits confirmation of the transaction(s) initiated at block  1380 . In some implementations, such an interim token may be useable by the system for certain types of further authorizations, or in a manner similar to the “token” described herein and in the &#39;500 Publication. 
       FIG. 15  is a flowchart illustrating confirmation of authorization transactions, according to an embodiment. As with  FIG. 13 , the operations of  FIG. 15  may be performed by the permissioning module  196  (and/or one or more additional aspects of the permissions management system  1204 ), in coordination with one or more of the permissions plug-ins  1280  and/or  1281  of  FIG. 12B . Additionally, in various embodiments, and as described herein, certain blocks of the flowchart may be omitted, or ordered differently, or additional blocks may be added. 
     At block  1510 , the system awaits confirmation of the one or more authorization transactions initiated in  FIG. 13  (e.g., at block  1380 ). In one embodiment, the system can determine whether there is support for user account data (e.g., transaction information) to be pulled from that particular external user account system, for example, using an institution interface module. If there is such support for automatically accessing user account data of the user account (e.g., at block  1520 ), at block  1530 , the system can continue with the second fallback authorization mechanism and pull transaction information to verify and confirm the authorization transactions. Then the system, at block  1550 , can use the pulled transaction information to compare the one or more authorization parameters of the transactions. For example, and without limitation, the system can compare transaction types (e.g., credit transaction, debit transaction, and/or the like), transaction descriptions, transaction amounts, transaction identifiers, and/or other transaction metadata (e.g., datestamps, timestamps, sources, and/or the like) to verify and confirm that the initiated authorization transactions resulted in the intended transaction associated with the correct user account. As described above, if the authorization parameters match, at block  1560 , then the system can proceed to block  1570  with the process of authorizing further activity on the user account. This can involve, for example, by changing the state of a token associated with the user account. The user can be notified that the account access has been authorized in a user interface, such as the one depicted in  FIG. 16B . If not, at block  1580 , the system can flag the account linkage as not authorized and can proceed with another attempt with one or more fallback authorization mechanisms, or can proceed with alternative security procedures in order to further protect the user account. In an implementation, at optional block  1561  the system can optionally allow the user to provide manual confirmation or verification that the authorization parameters match. If confirmed, the system can proceed with block  1570 . 
     d. Example Third Fallback Authorization Mechanism 
     At block  1520 , if the identified institution does not support automatic user account data (e.g., transaction information) access, the permissions management system  1204  may proceed with operations associated with a third fallback authorization mechanism. 
     For example, according to an implementation, where a user cannot or does not desire to provide account credentials associated with a user account, where user account credentials associated with the user account do not exist or are not supported by the external user account system, or where the external user account system associated with the user account does not provide support for the primary authorization mechanism or the first or second fallback authorization mechanisms (or the primary authorization mechanism and/or the first and/or second fallback authorization mechanisms fail), the system may automatically use a third fallback authorization mechanism to securely authorize access to the user account and/or securely authorize initiation or execution of transactions related to the user account. The third fallback authorization mechanism may include the system obtaining institution and/or account identifiers (e.g., a routing number and an account number associated with the user account) associated with the user account from the user. The third fallback authorization mechanism may also include the system initiating one or more authorization transactions (e.g., deposit(s)) to the user account, subsequently requesting that the user provide information related to the one or more authorization transactions (e.g., amounts of the deposit(s) shown in the user account, as obtained by the user via another channel different from the system), and using the user-provided information to verify the one or more authorization transactions (e.g., to verify amounts of the deposit(s) provided by the user match the amounts of the deposit(s) initiated by the system). As with the second fallback authorization mechanism, with the third authorization mechanism the one or more authorization transactions may be verified based on one or more authorization parameters (e.g., as included in the user-provided information) related to the authorization transactions, such as transaction amounts, transaction identifiers, and/or transaction metadata (e.g., datestamps, timestamps, sources, and/or the like). Thus, the one or more authorization transactions may be verified by matching of one or more authorization parameters. Under the third fallback authorization mechanism, if the one or more authorization transactions are verified, the system may then be authorized to access the user account and/or to initiate or execute transactions related to the user account. The system may accomplish ongoing access to the user account and/or initiation or execution of transactions related to the user account via, e.g., and as with the primary authorization mechanism and the first and second fallback authorization mechanisms, simulated instance(s) of software application(s) and/or APIs of the external user account system, as described herein. Revocable authorization for others (e.g., an external user-facing system/application) to access to the user account and/or initiate or execute transactions related to the user account may then be accomplished via the generation and issuing of a token, as described herein. 
     Thus, returning to  FIG. 15 , at block  1540 , the system can proceed with a third fallback authorization mechanism for confirming the transaction parameters. For example, the permissions plug-in can be used to present user interfaces to have the user input authorization parameters based, for example, on their independent access to transaction information about their user account on the external user account system. The user can be notified that the transaction attempts have been made, for example in one embodiment, by presenting an interactive user interface such as the one depicted in  FIG. 14C .  FIG. 16A  illustrates another example interactive user interface, according to one embodiment, in which the user is later requested to confirm the amounts associated with two transactions initiated on their user account. The user interface can be readily modified to have the user input any authorization parameter advantageous for confirming the transaction(s). Returning again to  FIG. 15 , at block  1550 , the parameters input by the user are compared with the transaction information retained by the system when the transactions were initiated in  FIG. 13 . As described above, if the authorization parameters match, at block  1560 , then the system can proceed to block  1570  with authorizing further activity on the user account. This can involve, for example, by changing the state of a token associated with the user account. The user can be notified that the account access has been authorized in a user interface, such as the one depicted in  FIG. 16B . If the parameters do not match, then the user can be presented with a user interface notifying the user that the account authorization process did not succeed, for example using a user interface such as the one depicted in  FIG. 16C . An option to retry the authorization mechanism can be offered, as depicted in  FIG. 16C . If the user makes too many attempts with the authorization flow, the user account can be protected by security procedures which present a security user interface, such as the one depicted in  FIG. 16D . In an implementation, at optional block  1561  the system can optionally allow the user to provide manual confirmation or verification that the authorization parameters match. If confirmed, the system can proceed with block  1570 . 
     e. Additional Aspects of Authorization Mechanisms 
     In various embodiments, the one or more authorization mechanisms may be ordered or prioritized differently than as described herein. For example, in an embodiment, the first fallback authorization mechanism as described herein may instead be prioritized as the primary authorization mechanism. Other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     Similarly, in various embodiments, certain features and variations of the one or more authorization mechanisms may be different from those described herein. For example, in an embodiment, the primary authorization mechanism may not include automatic access of institution and/or account identifiers. Rather, the primary authorization mechanism may initially provide secure authorization to access a user account, which authorization may be followed (immediately, or at some later point in time) by the first fallback authorization mechanism to provide secure authorization to initiate or execute transactions related to the user account (e.g., by obtaining institution and/or account identifiers from the user and matching/verifying those institution and/or account identifiers). Thus, in this embodiment, the primary authorization mechanism may be understood as a first primary authorization mechanism to access the user account (and associated user account data), and the first fallback authorization mechanism may be understood as a second primary authorization mechanism to initiate or execute transactions related to the user account (which may then be followed by one or more fallback authorization mechanisms, such as the second and third fallback authorization mechanisms, as described herein). As noted above, other combinations, orderings, and priorities of the one or more authorization mechanisms are also contemplated by the present disclosure. 
     While note shown in the example user interfaces or the flow charts, in various implementations, and in various of the one or more authorization mechanisms, in response to the user providing an indication/selection of an institution, the system may, via the permissions plug-in, provide a listing of user accounts of the user at the institution. The user may then select one of the listed user accounts for proceeding with various functionality described herein (e.g., the one or more authentication mechanisms, account access, transactions initiation, etc.). 
     In various implementations, authorization parameters will often provide information regarding characteristics of the user account relevant to future processing and that can be captured in an electronic record associated with the user account and associated authorizations. For example, and without limitation, if a first transaction attempting to initiate a credit to an account succeeds but a second transaction attempting to initiate a debit from an account fails, this would mean that the user account has limited functionality at the external user account system. This characteristic can be recorded in the user account electronic record so that future transactions on the user account, or on other user accounts at the external user account system, can take that characteristic into account during processing. 
     Advantageously, the one or more authorization mechanisms including, e.g., the primary authorization mechanism and the one or more fallback authorization mechanisms, may enable multiple paths for secure and automated and/or semi-automated user account authorization. Advantageously, the one or more authorization mechanisms may enable adaptation of the system to the capabilities of various external user account systems. Advantageously, the system may further enable authorizations to access user accounts and/or initiate or execute transactions related to user accounts to be provided to an external user-facing system/application, without disclosing institution and/or account identifiers or account credentials to the external user-facing system/application. For example, the disclosure includes, in some embodiments, automatic generation of electronic records that securely store account information (e.g., account credentials and/or account identifiers). In some implementations the electronic records may include one or more permissions related to the account and the external user-facing system/application. A token (e.g., a unique identifier associated with the electronic record, also referred to herein as a “unique record identifier”) may be shared with the external user-facing system/application, but in some implementations neither the electronic record itself, nor the institution and/or account identifiers or credentials, may be shared with the external user-facing system/application. Accordingly, the external user-facing system/application (e.g., a merchant system or a software application developed by a developer) may request user account data and/or initiate transactions by providing the token, but does not itself know, e.g., account numbers, etc. Further, in some implementations the user may set various permissions related to the token/electronic record, and may also revoke permissions associated with the token/electronic record (e.g., de-authorize the external user-facing system/application), thus providing increased security to the user&#39;s account. The disclosure further includes various interactive user interfaces and functionality to facilitate the above-described functionality. 
     VIII. Additional Implementation Details and Embodiments 
     In an implementation the system  100 / 1208  (or one or more aspects of the system) may comprise, or be implemented in, a “virtual computing environment”. As used herein, the term “virtual computing environment” should be construed broadly to include, for example, computer readable program instructions executed by one or more processors (e.g., as described above in the example of  FIG. 11 ) to implement one or more aspects of the modules and/or functionality described herein. Further, in this implementation, one or more modules/engines/etc. (e.g., as described in reference to  FIG. 11  and throughout this application) of the system may be understood as comprising one or more rules engines of the virtual computing environment that, in response to inputs received by the virtual computing environment, execute rules and/or other program instructions to modify operation of the virtual computing environment. For example, a communication received from a user computing device may be understood as modifying operation of the virtual computing environment to cause a module/engine of the system to gather data associated with the communication, communicate with other computer devices/systems via one or more APIs, and/or the like. Such functionality may comprise a modification of the operation of the virtual computing environment in response to inputs and according to various rules. Other functionality implemented by the virtual computing environment (as described throughout this disclosure) may further comprise modifications of the operation of the virtual computing environment, for example, the operation of the virtual computing environment may change depending on the information gathered by via various APIs. Initial operation of the virtual computing environment may be understood as an establishment of the virtual computing environment. In some implementations the virtual computing environment may comprise one or more virtual machines, containers, and/or other types of emulations of computing systems or environments. In some implementations the virtual computing environment may comprise a hosted computing environment that includes a collection of physical computing resources that may be remotely accessible and may be rapidly provisioned as needed (commonly referred to as “cloud” computing environment). 
     Implementing one or more aspects of the system as a virtual computing environment may advantageously enable executing different aspects or modules of the system on different computing devices or processors, which may increase the scalability of the system. Implementing one or more aspects of the system as a virtual computing environment may further advantageously enable sandboxing various aspects, data, or modules of the system from one another, which may increase security of the system by preventing, e.g., malicious intrusion into the system from spreading. Implementing one or more aspects of the system as a virtual computing environment may further advantageously enable parallel execution of various aspects or modules of the system, which may increase the scalability of the system. Implementing one or more aspects of the system as a virtual computing environment may further advantageously enable rapid provisioning (or de-provisioning) of computing resources to the system, which may increase scalability of the system by, e.g., expanding computing resources available to the system or duplicating operation of the system on multiple computing resources. For example, the system may be used by thousands, hundreds of thousands, or even millions of users simultaneously, and many megabytes, gigabytes, or terabytes (or more) of data may be transferred or processed by the system, and scalability of the system may enable such operation in an efficient and/or uninterrupted manner. In another scenario, the system may be accessing data items from multiple data sources. There may be multiple sets of subroutines or sub-processes which can be used to access data from multiple data sources, with each set of subroutines specifically tailored to a specific data source. Since the necessary data items and the corresponding data sources may be determined beforehand, the efficiency of the system is improved by allowing the system to obtain data from multiple data sources at the same time. 
     In an embodiment, any or all of the modules and engines of the system are configured to act in real time or substantially real time. Thus, when data is received by the modules, the modules process that data as soon as practicable or necessary to provide users with timely information. In order to achieve this, specialized hardware may be used to gain efficiency, and executable code may be designed to minimize latency or computation time. In an embodiment, the modules, possibly with other modules of the system, are executed within a real-time operating system, to enhance the responsiveness of the system. Various embodiments of the present disclosure may be a system, a method, and/or a computer program product at any possible technical detail level of integration. The computer program product may include a computer readable storage medium (or mediums) having computer readable program instructions thereon for causing a processor to carry out aspects of the present disclosure. 
     The functionality described herein may be performed as software instructions are executed by, and/or in response to software instructions being executed by, one or more hardware processors and/or any other suitable computing devices. The software instructions and/or other executable code may be read from a computer readable storage medium (or mediums). 
     The computer readable storage medium can be a tangible device that can retain and store data and/or instructions for use by an instruction execution device. The computer readable storage medium may be, for example, but is not limited to, an electronic storage device (including any volatile and/or non-volatile electronic storage devices), a magnetic storage device, an optical storage device, an electromagnetic storage device, a semiconductor storage device, or any suitable combination of the foregoing. A non-exhaustive list of more specific examples of the computer readable storage medium includes the following: a portable computer diskette, a hard disk, a solid state drive, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or Flash memory), a static random access memory (SRAM), a portable compact disc read-only memory (CD-ROM), a digital versatile disk (DVD), a memory stick, a floppy disk, a mechanically encoded device such as punch-cards or raised structures in a groove having instructions recorded thereon, and any suitable combination of the foregoing. A computer readable storage medium, as used herein, is not to be construed as being transitory signals per se, such as radio waves or other freely propagating electromagnetic waves, electromagnetic waves propagating through a waveguide or other transmission media (e.g., light pulses passing through a fiber-optic cable), or electrical signals transmitted through a wire. 
     Computer readable program instructions described herein can be downloaded to respective computing/processing devices from a computer readable storage medium or to an external computer or external storage device via a network, for example, the Internet, a local area network, a wide area network and/or a wireless network. The network may comprise copper transmission cables, optical transmission fibers, wireless transmission, routers, firewalls, switches, gateway computers, and/or edge servers. A network adapter card or network interface in each computing/processing device receives computer readable program instructions from the network and forwards the computer readable program instructions for storage in a computer readable storage medium within the respective computing/processing device. 
     Computer readable program instructions (as also referred to herein as, for example, “code,” “instructions,” “module,” “application,” “software application,” and/or the like) for carrying out operations of the present disclosure may be assembler instructions, instruction-set-architecture (ISA) instructions, machine instructions, machine dependent instructions, microcode, firmware instructions, state-setting data, configuration data for integrated circuitry, or either source code or object code written in any combination of one or more programming languages, including an object oriented programming language such as Smalltalk, C++, or the like, and procedural programming languages, such as the “C” programming language or similar programming languages. Computer readable program instructions may be callable from other instructions or from itself, and/or may be invoked in response to detected events or interrupts. Computer readable program instructions configured for execution on computing devices may be provided on a computer readable storage medium, and/or as a digital download (and may be originally stored in a compressed or installable format that requires installation, decompression or decryption prior to execution) that may then be stored on a computer readable storage medium. Such computer readable program instructions may be stored, partially or fully, on a memory device (e.g., a computer readable storage medium) of the executing computing device, for execution by the computing device. The computer readable program instructions may execute entirely on a user&#39;s computer (e.g., the executing computing device), partly on the user&#39;s computer, as a stand-alone software package, partly on the user&#39;s computer and partly on a remote computer or entirely on the remote computer or server. In the latter scenario, the remote computer may be connected to the user&#39;s computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or the connection may be made to an external computer (for example, through the Internet using an Internet Service Provider). In some embodiments, electronic circuitry including, for example, programmable logic circuitry, field-programmable gate arrays (FPGA), or programmable logic arrays (PLA) may execute the computer readable program instructions by utilizing state information of the computer readable program instructions to personalize the electronic circuitry, in order to perform aspects of the present disclosure. 
     Aspects of the present disclosure are described herein with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the disclosure. It will be understood that each block of the flowchart illustrations and/or block diagrams, and combinations of blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer readable program instructions. 
     These computer readable program instructions may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions/acts specified in the flowchart and/or block diagram block or blocks. These computer readable program instructions may also be stored in a computer readable storage medium that can direct a computer, a programmable data processing apparatus, and/or other devices to function in a particular manner, such that the computer readable storage medium having instructions stored therein comprises an article of manufacture including instructions which implement aspects of the function/act specified in the flowchart(s) and/or block diagram(s) block or blocks. 
     The computer readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable apparatus or other device to produce a computer implemented process, such that the instructions which execute on the computer, other programmable apparatus, or other device implement the functions/acts specified in the flowchart and/or block diagram block or blocks. For example, the instructions may initially be carried on a magnetic disk or solid state drive of a remote computer. The remote computer may load the instructions and/or modules into its dynamic memory and send the instructions over a telephone, cable, or optical line using a modem. A modem local to a server computing system may receive the data on the telephone/cable/optical line and use a converter device including the appropriate circuitry to place the data on a bus. The bus may carry the data to a memory, from which a processor may retrieve and execute the instructions. The instructions received by the memory may optionally be stored on a storage device (e.g., a solid state drive) either before or after execution by the computer processor. 
     The flowchart and block diagrams in the Figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of instructions, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the blocks may occur out of the order noted in the Figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In addition, certain blocks may be omitted in some implementations. The methods and processes described herein are also not limited to any particular sequence, and the blocks or states relating thereto can be performed in other sequences that are appropriate. 
     It will also be noted that each block of the block diagrams and/or flowchart illustration, and combinations of blocks in the block diagrams and/or flowchart illustration, can be implemented by special purpose hardware-based systems that perform the specified functions or acts or carry out combinations of special purpose hardware and computer instructions. For example, any of the processes, methods, algorithms, elements, blocks, applications, or other functionality (or portions of functionality) described in the preceding sections may be embodied in, and/or fully or partially automated via, electronic hardware such application-specific processors (e.g., application-specific integrated circuits (ASICs)), programmable processors (e.g., field programmable gate arrays (FPGAs)), application-specific circuitry, and/or the like (any of which may also combine custom hard-wired logic, logic circuits, ASICs, FPGAs, etc. with custom programming/execution of software instructions to accomplish the techniques). 
     Any of the above-mentioned processors, and/or devices incorporating any of the above-mentioned processors, may be referred to herein as, for example, “computers,” “computer devices,” “computing devices,” “hardware computing devices,” “hardware processors,” “processing units,” and/or the like. Computing devices of the above-embodiments may generally (but not necessarily) be controlled and/or coordinated by operating system software, such as Mac OS, iOS, Android, Chrome OS, Windows OS (e.g., Windows XP, Windows Vista, Windows 7, Windows 8, Windows 10, Windows Server, etc.), Windows CE, Unix, Linux, SunOS, Solaris, Blackberry OS, VxWorks, or other suitable operating systems. In other embodiments, the computing devices may be controlled by a proprietary operating system. Conventional operating systems control and schedule computer processes for execution, perform memory management, provide file system, networking, I/O services, and provide a user interface functionality, such as a graphical user interface (“GUI”), among other things. 
     As described above, in various embodiments certain functionality may be accessible by a user through a web-based viewer (such as a web browser), or other suitable software program). In such implementations, the user interface may be generated by a server computing system and transmitted to a web browser of the user (e.g., running on the user&#39;s computing system). Alternatively, data (e.g., user interface data) necessary for generating the user interface may be provided by the server computing system to the browser, where the user interface may be generated (e.g., the user interface data may be executed by a browser accessing a web service and may be configured to render the user interfaces based on the user interface data). The user may then interact with the user interface through the web-browser. User interfaces of certain implementations may be accessible through one or more dedicated software applications. In certain embodiments, one or more of the computing devices and/or systems of the disclosure may include mobile computing devices, and user interfaces may be accessible through such mobile computing devices (for example, smartphones and/or tablets). 
     Many variations and modifications may be made to the above-described embodiments, the elements of which are to be understood as being among other acceptable examples. All such modifications and variations are intended to be included herein within the scope of this disclosure. The foregoing description details certain embodiments. It will be appreciated, however, that no matter how detailed the foregoing appears in text, the systems and methods can be practiced in many ways. As is also stated above, it should be noted that the use of particular terminology when describing certain features or aspects of the systems and methods should not be taken to imply that the terminology is being re-defined herein to be restricted to including any specific characteristics of the features or aspects of the systems and methods with which that terminology is associated. 
     Conditional language, such as, among others, “can,” “could,” “might,” or “may,” unless specifically stated otherwise, or otherwise understood within the context as used, is generally intended to convey that certain embodiments include, while other embodiments do not include, certain features, elements, and/or steps. Thus, such conditional language is not generally intended to imply that features, elements and/or steps are in any way required for one or more embodiments or that one or more embodiments necessarily include logic for deciding, with or without user input or prompting, whether these features, elements and/or steps are included or are to be performed in any particular embodiment. 
     The term “substantially” when used in conjunction with the term “real-time” forms a phrase that will be readily understood by a person of ordinary skill in the art. For example, it is readily understood that such language will include speeds in which no or little delay or waiting is discernible, or where such delay is sufficiently short so as not to be disruptive, irritating, or otherwise vexing to a user. 
     Conjunctive language such as the phrase “at least one of X, Y, and Z,” or “at least one of X, Y, or Z,” unless specifically stated otherwise, is to be understood with the context as used in general to convey that an item, term, etc. may be either X, Y, or Z, or a combination thereof. For example, the term “or” is used in its inclusive sense (and not in its exclusive sense) so that when used, for example, to connect a list of elements, the term “or” means one, some, or all of the elements in the list. Thus, such conjunctive language is not generally intended to imply that certain embodiments require at least one of X, at least one of Y, and at least one of Z to each be present. 
     The term “a” as used herein should be given an inclusive rather than exclusive interpretation. For example, unless specifically noted, the term “a” should not be understood to mean “exactly one” or “one and only one”; instead, the term “a” means “one or more” or “at least one,” whether used in the claims or elsewhere in the specification and regardless of uses of quantifiers such as “at least one,” “one or more,” or “a plurality” elsewhere in the claims or specification. 
     The term “comprising” as used herein should be given an inclusive rather than exclusive interpretation. For example, a general purpose computer comprising one or more processors should not be interpreted as excluding other computer components, and may possibly include such components as memory, input/output devices, and/or network interfaces, among others. 
     While the above detailed description has shown, described, and pointed out novel features as applied to various embodiments, it may be understood that various omissions, substitutions, and changes in the form and details of the devices or processes illustrated may be made without departing from the spirit of the disclosure. As may be recognized, certain embodiments of the inventions described herein may be embodied within a form that does not provide all of the features and benefits set forth herein, as some features may be used or practiced separately from others. The scope of certain inventions disclosed herein is indicated by the appended claims rather than by the foregoing description. All changes which come within the meaning and range of equivalency of the claims are to be embraced within their scope.