At amBrain, I delivered backend development, integrations, and testing for fintech, e-commerce, and enterprise communication products. On a cryptocurrency exchange, I owned the end-to-end SumSub KYT / Travel Rule integration, including verified webhooks, durable queued delivery, and historical transaction backfills.
I fixed a race condition that could send a crypto withdrawal twice by changing when its status was committed and guarding against repeat sends. I also standardized money handling with BCMath strings and added feature tests for exchange rates, commissions, and exchange logic.
Across a 14-microservice e-commerce platform, I built gift-certificate features and implemented coupon and loyalty mechanics spanning multiple services. I kept related service data consistent through RabbitMQ messaging and scheduled retries for failed 1C and Mindbox synchronization.
For an enterprise communication platform, I developed REST APIs and chat features, integrating Laravel Broadcasting with a Node.js WebSocket service for real-time messaging. I also built isolated test infrastructure for the e-commerce users service and authored 33 of its 78 feature-test files.
