Software Engineer

TS

Three Sigma

Software Engineering
London, UK
GBP 45k-55k / year + Equity
Posted on Oct 5, 2025

Location

London

Employment Type

Full time

Location Type

Hybrid

Department

Engineering

Deadline to Apply

October 16, 2025 at 7:00 PM EDT

Compensation

  • Software EngineerSalary £45K – £55K • 0.25% – 0.5%

Location: London (Hybrid, 4 days/week in office) • Team: Early engineering • As: Full-stack engineer

Why this role

Ship useful software fast. You’ll design, build, and own features end-to-end in a small team working directly with the founders. You’ll build and ship features that matter, take real ownership of your work, and grow quickly as part of a high-velocity team.

What You’ll Do

  • Design, build, and ship user-facing features across the stack.

  • Develop and maintain REST APIs and backend services with scalable, maintainable designs.

  • Implement secure data flows and integrations.

  • Build complex workflow tools and interactive UIs (think editors, tables, real-time updates).

  • Keep quality high through tests, reviews, and clear, simple code.

  • Work directly with founders and product from concept to release + iteration.

What We’re Looking For

  • Startup mindset: bias for action, ability to work independently, comfort with ambiguity.

  • Strong fundamentals: solid grounding in computer science (data structures, algorithms, systems).

  • Full-stack skills: React/TypeScript or similar on the frontend, Python/Django (or another MVC framework) on the backend.

  • Track Record: ~2+ years professional experience or open-source/projects that show you can build and ship.

  • Collaboration: strong communication, team-first attitude.

Nice to Have

  • Experience with Next.js or modern server-side frameworks.

  • Familiarity with component libraries/design systems.

  • Curiosity for DevOps, CI/CD, or infra as code.

Why Join Us

  • Ownership: we expect every engineer to think beyond code, shaping product and architecture.

  • Learning & Growth: work directly with founders in a fast-paced environment.

  • Startup energy: small team, ambitious mission, rapid iteration, big upside.

Compensation Range: £45K - £55K