I’m Marcin Krysiński — I design and build backend systems in Node.js & TypeScript. APIs, data layers, event pipelines and the microservices that hold them together.
I’ve spent my career in the parts of software users never see — the APIs, databases, queues and services that have to stay correct under load. I work primarily in Node.js and TypeScript.
A focused stack I know deeply — chosen to fit the problem
The runtime behind every service I ship — event-driven and fast to iterate.
Strict types across the service boundary, so refactors are safe, not scary.
Typed schemas that hand each client exactly the data it asks for — nothing more.
Relational data done properly: real constraints, considered indexes, honest queries.
Auth, realtime data and managed backends when speed to launch is what matters.
Queues and event streams that decouple services and absorb back-pressure.
Independently deployable services with clear contracts between them.
REST and GraphQL APIs modeled around your domain — typed end to end, documented, and built to evolve.
Splitting a monolith, or designing services that stay independently deployable with clear contracts.
PostgreSQL schema design, query tuning, and caching that survives a real traffic spike.
Brokers, queues and background workers with idempotency and back-pressure built in from the start.
Structured logs, metrics and traces so you find the regression before your customers do.
An audit of an existing backend: correctness, security, performance, and the parts that wake you at 3am.
You brief the person who writes the code. Questions get answered the same day, not relayed through a project manager.
I’d rather ship the boring, correct version than the clever one. Constraints, types and tests do the heavy lifting.
Success is a system you stop thinking about — observable, idempotent, and calm when traffic spikes.
A short note is plenty — a new API, a rescue, a performance review. I’ll reply within two business days with next steps or a few questions.
I’ll be in touch shortly. Prefer email? Reach me directly at marcin_krysinski@outlook.com .