Blockchains also introduced the concept of smart contracts, which are code stored in the blockchain that is executed after reaching certain conditions, without the need for trustful entities or third-party supervision. In contrast to classical applications, the backend of a DApp relies on such contracts, which are immutable and indisputable. The security provided by a blockchain provides smart contracts with a great potential for implementing multiple practical applications [17], but they need to be secure against possible attacks [18]. As it will be later detailed in Section 2, there have been previous attempts to implement blockchain-based solutions for academic document verification. However, most of such solutions focus on the verification of academic certificates, not considering the continuous monitoring of the Academic Records (ARs). Such academic history can be tracked and verified, as it becomes clear that fraud can come through the student's career and not only at its end. Although in recent years blockchain applications have become popular, they have also been criticized for having low performance, being too energy intensive or not decentralized enough [19]. The latest research has been devoted to the analysis of different techniques to benchmark and to optimize its operation, leading to what is called green blockchain [20; 21; 22]. These novel techniques pave the way to mass adoption, as these would turn blockchain technologies as efficient as many centralized systems, as well as benefiting from all the advantages provided by decentralization. In addition, evaluations involving low-power devices in proof-of-concept implementations are still scarce in the current literature and are rarely explored in depth. In contrast, while recent research has made significant contributions to academic verification, it still presents certain gaps and limitations. Specifically, there are areas that have not been fully explored or adequately addressed, opening the opportunity for new applications. Considering the previously mentioned issues, this article describes a blockchain-based solution for verifying the authenticity of ARs and professional merits. Such a solution relies on a DApp that makes use of a decentralized database [23] based on the Inter-Planetary File System (IPFS) protocol [24], which stores the raw off-chain data. Such data identify and track the academic information through the use of hashes that are stored in the blockchain [25]. The traceability and immutability of ARs is guaranteed with a hash that represents any kind of raw data (in this case, off-chain data) and that represents the changes in the data through their updates. The developed DApp can verify not only academic certificates, but also the complete academic career of a student. The low complexity and time required by the proposed solution to perform the verification avoids the vast amount of bureaucracy usually involved in this kind of validation. Moreover, these records can also be verified after the issue of an academic certificate, as well as before the student obtains his/her degree. Overall, the proposed system allows:  
* Students to share their ARs with any third-party, so that they can be verified. * Administrators to custody the validity of the changes. With the hashing technique, any minor change in an AR stored in the database will completely transform its hash, so administrators will always be aware of such changes. * Third-parties to easily and efficiently verify an AR, as they simply need to introduce the AR provided by a student. The performance of the proposed approach was evaluated as described later in Section 5, emphasizing energy efficiency and scalability. All the code of the developed DApp is available as open-source (under GPL-3.0 license), so it can be downloaded from GitHub [26] and then be used and/or modified by future researchers and developers. It is important to note that a preliminary version of the work presented in this article was previously published as a conference paper [27].