Software engineer @ 🎽 Pay

Tunic Pay
Tunic Pay

Software Engineering

Posted on Aug 5, 2026
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We’re looking for a creative, experienced software engineer based in London to join our fintech startup at the ground floor. If you are excited about independence, impact, and contributing to the battle against scams and financial crime, read on to learn more ⬇️

About the role 🎭

Banks approve or reject payments with almost no context. We're building the intelligence layer that changes that — running real-time investigations on payments before they clear. The technical challenge is to orchestrate multi-source evidence gathering, synthesize unstructured data with AI agents, and return a nuanced evaluation in the shortest possible time and with the greatest possible reliability.

What you’ll work on

  • Build and evolve the APIs and UIs that banks use to integrate our investigation engine into their payment flows
  • Connect our investigation engine to the data it needs: third-party APIs, unstructured documents, scraped sources, and whatever else works. Some sources have clean APIs, but most don’t.
  • Design the orchestration layer that coordinates evidence gathering across heterogeneous sources (some structured, most not)
  • Ship reliable code with strong emphasis on usability, security, and observability
  • Make build/buy and now/later decisions about a rapidly evolving codebase. Clearly communicate trade-offs and own the consequences
  • AI: yes, experimentation, endlessly. Experiment with and deploy specialised AI agents — we’re actively shipping LLM-powered investigation flows, not just prototyping.
  • Team: Participate in planning based on customer feedback and engage in effective code reviews (on both sides of the table!)

    • This is not a feature factory role — engineers here drive product decisions and own systems end-to-end: design, build, ship, observe, and iterate.

    Why this is hard

    Most payments are legitimate and should flow without friction. But some are scams, and the evidence that distinguishes them is messy — unstructured, scattered across sources, rarely behind clean APIs. We need to make that judgment fast enough that good payments aren't delayed, while applying progressive friction when risk warrants it. Banks need to understand our reasoning, not just our scores. And we're critical infrastructure: when we're wrong or unavailable, real people lose money or can't move it.

    Our stack today:

  • Backend: Python, Kotlin
  • Frontend: TypeScript, React
  • Infra: Cloud-native, event-driven services, async workflows (GCP managed using Terraform)
  • Data: SQL-first, correctness > dashboards

    • But honestly, if you’ve built fault-tolerant distributed systems before, the specific tools matter less than your judgement on when to reach for them.

    About YOU 🦄

    Here are some thoughts on who would be successful in the role. We know we won’t be able to assess these from your CV, but our interview process will be designed around them:

  • Product ownership: you ask “who is the user, what’s the job-to-be-done, what’s the smallest useful thing we can ship?” and you don’t wait for perfect specs and instead create solutions & communicate tradeoffs.
  • Systems thinkings: You have experience in building fault-tolerant distributed systems. You think about how components fit together and anticipate knock-on effects.
  • Collaboration: You’re direct, pro-active, generous to others, and low ego. No bug is too small if an outcome or colleague depends on it!

    • Some hard skills we’d value

  • Architecture: Experience building and maintaining fault-tolerant distributed systems.
  • Data: Ability to develop and manage well-functioning databases. Experience working in sensitive data contexts and good understanding of data governance practices and privacy concerns.
  • Years of experience: 5 or more. We’re looking for professionals who can structure their own work and be a strong technical voice for the team while getting their hands dirty (we’re not overly strict on exact number of years!).
  • Stage of experience: We value people who have worked in early stage companies and demonstrate fluency with ongoing speed: precision tradeoffs and iterativeness.
  • Industry: Prior experience in fintech is a huge plus.

    • Not got 100% of qualifications? Research shows that women and under-represented minorities are less likely to apply for a role if they do not have 100% of the requirements. We’re paying attention to this, so please feel free to apply regardless (<2mins) or send us a note on info@tunicpay.com if you’d like to discuss if there’s a fit.

    How to apply đź“„

    Yes! Apply here: ‣

    Apply now
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