Senior Software Engineer - Backend and Infrastructure

"Traders bring the performance. We build everything beneath it." About Prop League Trading is one of the most competitive pursuits in the world, and yet one of the least visible. Thousands of funded traders put real firms' capital and real nerve on the line every day, but the best of them can't prove it beyond screenshots. P&L resets when an account closes, results are scattered across firms and platforms, and real talent disappears into the noise. Prop League exists to change that. We bring every account a trader manages into one ecosystem and turn their performance into a competitive track record, from yearly seasons to weekly and monthly tournaments. At its heart is the Prop Rating: a single measure of skill that carries a trader's reputation from season to season and unlocks competitive entries you can only enter on merit. Traders get a stage and a name worth building. Prop firms get a clear way to spot emerging talent before anyone else does. It only works if every number is beyond question, and that's where you come in. The role Every number on a Prop League table has to be right: through the market open, a dropped connection, or a platform outage. Traders compete for those numbers, argue over them and stake their reputation on them. You'll build everything underneath them: the integrations, the data pipelines, the infrastructure and its security. The work is half building, half running. We're a small, senior team, so the systems you design are the ones that ship, and your decisions show up in the product every trading day. This role is for someone who wants to own a live system end to end, cares that every number is right, and leaves a codebase simpler than they found it. What you'll do Build and run trading-platform integrations: long-running real-time connections and scheduled data capture that stay correct through reconnects, retries, gaps and duplicates.Own the path from fills to results: reconciliation and verification, so every number holds up to scrutiny from traders and prop firms.Run production on AWS: ECS, KMS and networking defined as code, with monitoring that spots problems before traders do.Lead incident response: on-call, runbooks and blameless postmortems.Own platform security: credential encryption and key management, least-privilege access and security reviews.Keep PostgreSQL fast and safe as we grow: schema design, migrations, query performance, backups and recovery drills.Raise the bar on every change: review code with care, whoever or whatever wrote it, and simplify wherever complexity has crept in. What we're looking for We care more about what you've built and run than how many years you've been doing it. You've owned production backend systems end to end, including being on call for them.Strong TypeScript and Node.js. Depth in one backend ecosystem matters more than a long list of languages.Deep PostgreSQL experience: schema design, migrations, performance and access control.Production AWS experience: containers, IAM, KMS and VPC networking, managed as code.You've kept long-running services correct through disconnects, retries and restarts, and you think in idempotency and reconciliation.You use AI coding tools critically, and can say concretely where they help and where they fall short.You think security-first, write clearly, and stay steady when production breaks. Bonus points Experience with trading-platform or brokerage APIs, especially Tradovate, ProjectX or Rithmic.An interest in trading, or experience as a trader yourself. If you're new to futures, we'll teach you the basics.Security or compliance work in a regulated setting (SOC 2, ISO 27001, UK GDPR).Python, for data tooling and verification. Our stack TypeScript, Node.js, Next.js, React, PostgreSQL, Vercel and GitHub Actions. On AWS: ECS on Fargate, ECR, EC2, KMS, IAM, VPC and CloudWatch, managed with the AWS CDK. Integrations: Tradovate (NinjaTrader), ProjectX and Rithmic. What success looks like 30 days: you know the platform end to end, you've shipped to production, and you're on call for the systems you know.60 days: you own a core part of our data infrastructure, with the observability to prove it's healthy.90 days: you're shaping the platform roadmap and the engineering standards we build to. Why join Prop League £75,000–£90,000 base salary, depending on experience.Room to grow into technical leadership, up to CTO, as the team grows.Hybrid working, with regular days in London and flexible hours around the trading week.25 days' holiday plus UK bank holidays and a workplace pension.Real ownership of a live platform at a defining stage, in an industry that's growing fast.Join as part of the founding team, and help shape how Prop League builds and transforms the industry from the start. How to apply Apply here on LinkedIn with your CV, and tell us in a few lines about a production system you've owned. If you match most of this but not all, apply anyway. We'd still like to hear from you. Our process has three steps, and we'll get back to you after every one: Intro call (30 minutes).A system design conversation about a system you've run (60 minutes).A final conversation, then an offer. You'll need the right to work in the UK; we can't sponsor visas for this role. We welcome applicants from every background, and if you need adjustments at any stage, tell us and we'll make them. We're not accepting agency CVs for this role. Prop League will never ask candidates for money, bank details or trading-account logins during hiring. If a message claiming to be from us does, don't respond, and report it to careers@propleague.com.