The client operated a large-scale online trading platform connected to numerous external payment providers. As the platform evolved and the number of integrations continued to grow, the company needed to maintain software quality while migrating from a monolithic architecture to microservices. The challenge was to validate complex payment workflows, keep an extensive regression testing scope under control, and support reliable releases without disrupting business-critical transaction flows. The client required a QA partner capable of supporting large-scale financial systems, payment integrations, and long-term test automation initiatives.
To support the client’s migration to microservices and growing payment ecosystem, a1qa designed a QA strategy based on the Test Pyramid and shift-left testing principles. The approach helped maximize test coverage, keep testing efforts scalable, and maintain control over regression risks across business-critical transaction workflows.
The testing framework included:
Additionally, QA specialists combined it with shift-left testing, verifying the entire scope from the earliest requirements analysis stages to detect issues when they are cheaper and easier to fix.
Based on this strategy, a1qa established a multi-layered testing process where developers covered unit testing, QA automation engineers executed component and end-to-end tests, and manual QA specialists focused on critical business scenarios that required additional validation.
Having agreed on the testing strategy with the client, a1qa performed the following QA activities:
To help the client expedite software testing cycles, amplify overall coverage, and achieve failsafe operation of the payment module, a1qa specialists created and ran automated end-to-end and component tests. QA automation engineers developed a customized solution that accounted for the shared structure of approximately 80% of tests. This simplified the workflows, so the team did not have to create each test from the ground up. Moreover, this solution introduced a special naming system for all test utility classes, simplifying the process of understanding and maintaining the work performed by other experts. Finally, the engineers applied this new system to verify dynamic data fields within the software interface responsible for trading financial contracts, which successfully uncovered defects of various severity in the main branch before deployment.
a1qa experts also verified the operation of 34 third-party integrations with payment systems, including card processors, e-wallets, alternative payment methods (APMs), cryptocurrency payment gateways, and regional payment providers supporting international trading operations.
The quality control process covered payment transaction flows, data exchange, request and response processing, as well as interactions between the trading platform and external payment services, helping ensure stable and reliable operation across a complex payment ecosystem.
a1qa specialists conducted thorough regression testing to make sure that changes introduced during the migration to microservices did not compromise existing functionality. During testing, the experts covered all business-critical workflows, including those related to payments, integrations, transaction processing, etc.
