Senior Backend Performance Engineer (EU) - Node.js

We're hiring an engineer to build the backend infrastructure behind an exceptionally fast product — one that stays fast regardless of scale. The system is live and growing; your job is to drive latency down across every layer of the stack. This is a high-ownership role: you'll own backend performance across the platform and build custom infrastructure wherever off-the-shelf solutions can't keep up. What You'll Do Own backend performance across the platform — databases, APIs, queues, and background processing Design advanced caching and data synchronization systems Profile production systems and eliminate latency bottlenecks at every layer Build custom infrastructure where third-party solutions aren't fast enough Improve scalability while keeping response times low Work with feature teams to hit performance targets, and continuously benchmark against best-in-class SaaS products What We're Looking For Must have: 4+ years of backend engineering experience, including 4+ years building and scaling high-traffic production systems Proven track record of optimizing large-scale backend systems Deep expertise in Node.js, TypeScript, PostgreSQL, Redis, networking, and distributed systems Extensive experience with database optimization, caching, asynchronous processing, and API performance Experience building custom infrastructure instead of relying solely on third-party solutions Strong computer science fundamentals, algorithms, and systems design knowledge; exceptional engineering standards and attention to detail Experience building products where latency and scalability were critical to the business Nice to have: Experience with high-volume messaging or event-driven systems Experience at a startup or fast-moving product company Familiarity with performance observability tooling (profilers, tracing, APM)