Senior Backend Engineer (Python)

If you have not designed and shipped production REST APIs, worked hands-on with SQLAlchemy, and owned Python backend systems at real scale, this role is not the right fit right now.

• 5+ years of backend engineering experience, with at least 4 years writing production Python at a professional level.
• Proven experience designing and building REST APIs from scratch; not just consuming them. You understand versioning, error handling, authentication, and what makes an API a liability six months later.
• Production-level experience with SQLAlchemy, including complex queries, relationship management, and knowing when the ORM is the wrong tool.
• Strong working knowledge of relational databases; schema design, query optimisation, indexing, and understanding the cost of what you write.
• Experience with async processing and task queues in production, Celery or equivalent.
• You have owned systems end-to-end: built them, debugged them under pressure, and improved them based on what broke.
• Based in the Netherlands or open to relocating to Amsterdam or Groningen.

Paylogic is the ticketing and event operations platform behind some of Europe's biggest events. Tomorrowland runs on it. So does Paradiso. Millions of fans use our systems to buy tickets. Event organisers use them to run their operations end-to-end. We're looking for a Backend Engineer with solid Python experience to join the team in Amsterdam or Groningen. You ll work on systems that matter at scale, high-traffic ticketing shops, payment flows, automated payouts, and the internal tools that help events run smoothly, seen by millions of fans and thousands of event organisers. This is not a role for someone still building their Python foundation. You need to already have one. What you'll be working on Paylogic's backend has two distinct layers worth understanding before you apply. * Fan-facing systems. White-label ticket shops that go live the moment a high-demand event opens for sale. Throughput, reliability, and correctness under peak load are non-negotiable. This is where a poorly handled queue or a missing database index will cost someone their ticket and the start of their event experience. * Organiser-facing tools. The platform event organisers use to manage their events, configure ticket products, track payments, and handle operational workflows. Less visible to fans, but genuinely complex to model and maintain well. The kind of code that needs to still make sense in two years. Day-to-day, you'll be: * Designing and building Python services that are production-ready from day one, not retrofitted later. * Owning and shipping payment flows, payout logic, and REST API integrations end-to-end. * Diagnosing and solving performance problems at scale, not just in theory. * Driving technical decisions and contributing meaningfully to architecture discussions. * Keeping existing systems maintainable, not just shipping features on top of them. Tech stack: Python, FastAPI, Flask, Celery, Redis, Memcached, MySQL, SQLAlchemy. Testing: Pytest, Playwright, Selenium. Tooling: We use AI-assisted development using Claude Code. We encourage developers to use AI, but we re also critical of what it produces., Paylogic is part of EVENTIM, Europe's largest ticketing and live entertainment company, ranking as the world's number two provider. The client list runs from Tomorrowland and Andr Rieu to Comic Con and Zoute Grand Prix. The engineering challenges are as varied as the events.