FULLSTACK
DEVELOPER
MateuszGoszczycki
Real-time Systems
WebSocket auction engines, Socket.IO gateways with isolated rooms, atomic Prisma transactions.
Payment Infrastructure
Stripe Connect — seller onboarding, escrow payouts, webhook-driven state machines.
AI Pipelines
Gemini Vision verification, Bull queues with exponential backoff — zero blocking of user flows.
Client Delivery
Requirements gathering, feedback loops, stakeholder comms — delivered for a paying client on schedule, live at autosell.pl.
Available · Immediate start
Remote · CET · Open to relocation
Shipped for a real, paying client — autosell.pl is live with real users
Full ownership mindset — schema, API, UI, deployment, all mine
6 years running a kitchen under pressure — production incidents don't scare me
Career pivot from zero in 2 years — I learn fast and ship faster
Built and deployed a production automotive marketplace for a paying client, live at autosell.pl and used by real users.
- Delivered the full system end-to-end as a sole developer
- Built a search system with 30+ filters that ranks listings by relevance, not just date
- Implemented real-time messaging between buyers and sellers, with message history and read receipts
- Integrated TPay payment gateway for listing fees
- Implemented authentication and basic security features for production use
- Wrote integration tests with Jest and Supertest covering search filters, auth, and input validation
- Deployed to production using Docker on a Linux VPS
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Open toWork.
Seeking Mid-Level Full-Stack roles and ambitious projects. I take full ownership from architecture to deployment — remote-first, CET timezone.
Typically replies within 24 hours
© 2026 Mateusz Goszczycki · All rights reserved
Working globally · CET timezone