Volodymyr K.

Senior Full Stack Developer (5+ years) — APIs · Microservices · Data & Cloud I design and build reliable back ends that scale. For a decade I’ve turned business goals into secure APIs, resilient services, and clean data layers—speeding releases and reducing production noise. I’m comfortable joining greenfield builds or rescuing complex systems and leaving them faster, safer, and easier to maintain. How I can help Architecture & new services: domain modeling, microservices/monolith, event-driven patterns API-first delivery: REST/GraphQL/gRPC, versioning, rate limiting, pagination, OpenAPI docs Data layer: PostgreSQL/MySQL schema design, migrations, indexing, caching (Redis), search (Elasticsearch) Performance & reliability: profiling, queues/workers (Kafka/RabbitMQ/SQS), background jobs, circuit breakers, idempotency Security: OAuth2/JWT, RBAC/ABAC, secrets management, OWASP hardening, audit logs Integrations: payments (Stripe), email/SMS, 3rd-party partner APIs, SSO/IdPs DevOps enablement: Docker/Kubernetes, CI/CD, IaC basics (Terraform), observability dashboards and alerts Rescue & modernization: audits, refactors, test coverage, strangler pattern, cost optimization Tech stack Node.js/TypeScript (NestJS, Express) • Python (FastAPI, Django/DRF) • Go (Gin/Echo) • Java (Spring Boot when needed) • PostgreSQL/MySQL • MongoDB • Redis • Elasticsearch • Kafka/RabbitMQ/SQS • Docker/K8s • AWS/GCP/Azure • GitHub Actions/GitLab CI • OpenTelemetry, Prometheus/Grafana, ELK • Jest/pytest/go test, Pact for contract tests. What you get Maintainable code, predictable timelines, and transparent communication Practical suggestions to reduce scope and cloud cost—without cutting quality A partner who treats reliability, security, and documentation as non-negotiable Have a brief, repo, or backlog? Share it and I’ll reply with a short action plan—quick wins, timeline, and how we’ll measure success for your next release.