Open to opportunities

Serhii Vakulenchyk

@serhiivakulenchyk

Message

I build high-load Node.js payment systems with reliable event-driven transaction processing.

Georgia

Message

What I'm looking for

I'm looking to build reliable, high-load products end to end, especially around payments, event-driven systems, privacy-first mobile products, and practical AI-assisted engineering.

At Andersen Lab, I build payment services for a high-concurrency iGaming platform processing tens of thousands of transactions daily. I deliver multi-currency deposits and withdrawals, provider integrations, webhooks, reconciliation, and failure recovery.

I resolved duplicate callback race conditions with Redis-based distributed locks and scale zero-loss flows with Kafka and RabbitMQ. I also optimise MySQL and ClickHouse read paths, deploy through GitLab CI/CD, and lead production root-cause analysis using Coralogix.

Previously, I owned the data layer for Warner Music Group's ADA Hub at Enke Systems, supporting release distribution, DDEX/ERN exchange, PostgreSQL/Aurora, OpenSearch, and Oracle integration. My earlier full-stack work across Capgemini Engineering, Eastern Peak, EPAM Systems, and Sellbery helps me take features from backend architecture through React or Angular implementation.

Experience

Work history, roles, and key accomplishments

Current

Backend Node.js Developer

Current

Andersen Lab

Mar 2024 - Present (2 years 6 months)

Own payment services on a high-concurrency iGaming platform processing tens of thousands of transactions per day. Built integrations with international payment providers, resolved race conditions with Redis-based distributed locks, and optimized event-driven flows on Kafka and RabbitMQ.

TypeScript NodeJS NestJS TypeORM Kafka RabbitMQ MySQL Clickhouse Redis OpenSearch GraphQL REST React S3 Coralogix Docker Kubernetes GitLab CI CD

Senior Backend Engineer

Enke Systems

Apr 2023 - Mar 2024 (11 months)

Owned the data layer of a large TypeScript monorepo for a B2B music release management platform. Designed Prisma models, implemented DDEX/ERN exchange, built OpenSearch indexing, and integrated with legacy Oracle systems.

TypeScript NodeJS Fastify Prisma Knex PostgreSQL Oracle OpenSearch Redis AWS Lambda S3 Amazon SQS Step Functions Docker GitHub Actions Jest Test Containers

Full Stack Developer

Capgemini Engineering

Dec 2021 - Apr 2023 (1 year 4 months)

Refactored legacy modules, fixed message-queue backlog errors, optimized MySQL queries, and delivered new user-facing functionality. Conducted regular code reviews across the team.

TypeScript ES6 Angular React Redux NodeJS MySQL Gitlab Jira Figma

Backend Node.js Developer

Eastern Peak

Apr 2021 - Dec 2021 (8 months)

Led refactoring of the core service layer, rebuilt data synchronization between databases, and resolved queue-processing failures in the RabbitMQ pipeline.

NodeJS TypeScript REST APIs Socket.IO RabbitMQ PostgreSQL Gitlab Jira

Software Engineer

EPAM Systems

Apr 2020 - Apr 2021 (1 year)

As Backend Node.js Developer, owned architecture design and implementation on a scalable service, drove sprint planning, and built REST and Socket.IO services in TypeScript on MongoDB. As AngularJS Developer, delivered front-end modules and helped introduce a code review process.

TypeScript NodeJS MongoDB Angular Hybris Nginx REST APIs Socket.IO Bitbucket Gitlab Jira

Full Stack Developer

Sellbery

Aug 2018 - May 2020 (1 year 9 months)

Independently rewrote and shipped Facebook and Amazon marketplace integrations. Improved Angular application performance and built new product functionality with unit tests and database migration scripts.