Building the Future of Finance: Payment Gateway System Design with Cryptocurrency
Tags: cryptocurrency, systemdesign, paymentgateway, aws
Published: 2023-09-15 08:41:52

# Overview

In the ever-evolving landscape of finance and technology, the concept of a Payment Gateway has become integral to our daily lives. Whether we're shopping online, transferring funds, or simply swiping a card, Payment Gateways seamlessly facilitate transactions, providing the bridge between customers and businesses. However, the world of payments is no longer confined to traditional currencies alone. With the advent of blockchain technology and cryptocurrencies, Payment Gateways have taken on a revolutionary new dimension, offering secure, transparent, and decentralized solutions. In this article, we will delve into the intricacies of Payment Gateway system architecture in the context of cryptocurrencies, exploring how this innovative fusion is shaping the future of financial transactions.

# Start with System Workflow

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/mq3dupj645lw67hylqfo.png)

### Explain the workflow:

1. Users request the Payment Gateway to create a new transaction.
2. The Payment Gateway interacts with the Blockchain through a network that requests users to create a new wallet address and store them in the database.
3. It then responds with the Wallet Address to the users who made the request.
4. Users proceed to send cryptocurrency to this wallet.
5. From the Payment Gateway, we will create some workers to track transactions on the wallet addresses we have created. When users send cryptocurrency, we can observe the transactions in these wallets on the blockchain.
6. Finally, we notify users when the transaction is completed and execute some business logic that we have defined.

# Simple System Design with AWS

Based on the workflow outlined above, I will design the system using AWS. This represents a simple architecture to initiate the project. As a minimalist, I always strive to commence my projects with a straightforward mindset, focusing on small tasks, simple thinking.

## Database design

### Transaction table

| Transaction ID | User Id | Wallet Address | Network | Amount | Status |
| --- | --- | --- | --- | --- | --- |
| 20230000001 | user_id_1 | 0x1234567890abcdefABCDEF1234567890abcdefAB | ERC20 | 0.00432 | Failed |
| 20230000003 | user_id_2 |  | ERC20 | 0.00231 | New |
| 20230000003 | user_id_3 | bnb1hgm0p7khfk85zpz5v0j8wnej3vmcftspee6l4p | BEP20 | 1.5 | Success |

The transaction table will store information about transactions that users create and map them to wallet addresses created on the blockchain. Below are some explanations of the field names in the table:

- **Transaction ID**: This is the ID of the transaction, which will be inserted when users request to create a new transaction.
- **User ID:** This field represents the ID of the user.
- **Wallet Address**: This field indicates the address of the wallet on the blockchain, which will be created in Step 2 of the workflow I described.
- **Network**: This field specifies the blockchain network.
- **Amount**: This field represents the amount of cryptocurrency.
- **Status**: This field will be updated when triggering a transaction of the wallet address on the blockchain.

There are also many other tables depending on your business, here I only mention the transaction table because it is directly related to the design of this system.

## Simple Architecture to kickstart:

![Image description](https://dev-to-uploads.s3.amazonaws.com/uploads/articles/14blic5xhvtbi41ld1gs.png)

I understand that this is a simple design for initiating a project. In reality, there will be numerous complex operations we need to take into consideration, such as security issues, project reliability, and usability of the system. We will need to address concerns like how to securely store wallet private keys, implement logging, monitoring, and error handling..etc..

I am a Java Backend Developer and a beginner in system architecture design, so there will inevitably be some shortcomings. I hope to receive everyone's support and contributions.