Senior Software Engineer

Thirdfort

Senior Software Engineer developing reliable, scalable systems for fraud prevention in financial transactions. Collaborating with cross-functional teams and leveraging AI tools for improvement.

Posted 5/28/2026full-timeRemote • 🇬🇧 United KingdomSenior💰 £70,000 - £85,000 per yearWebsite

Tech Stack

Tools & technologies

GoJavaScriptPythonTypeScript

About the role

Key responsibilities & impact

Design, build and ship well-tested features across our platform, with support from more senior engineers.
Take ownership of user stories from refinement through to production and post-release support.
Collaborate closely with Product and Design to understand problems and translate requirements into pragmatic technical solutions.
Write clean, maintainable code and contribute to improving code quality through reviews and refactoring.
Participate in incident investigation and support, helping to improve system reliability and observability over time.
Continuously develop your technical skills and broaden your understanding of the wider system.
Contribute positively to our engineering culture by sharing knowledge, asking questions, and supporting your teammates.
Incorporate AI tools and workflows into your day-to-day development practice, using them to move faster, reduce toil, and raise the quality bar, and share what you learn with the team.

Requirements

What you’ll need

You have experience building and shipping production software as part of a team.
You're confident working with modern backend and frontend technologies (for example Go, TypeScript, JavaScript, Python).
You understand core engineering fundamentals such as APIs, data modelling, testing, and version control.
You enjoy solving problems end-to-end and taking responsibility for your work.
You can communicate clearly with both technical and non-technical stakeholders.
You're happy working in a fast-moving environment where requirements may evolve as we learn more.
You're passionate about AI and actively use AI-powered tools (such as Cursor, Copilot, Claude or LLM APIs) in your development workflow, or you're genuinely eager to build those habits. We care about curiosity and enthusiasm here, not a specific tool or years of experience.

Benefits

Comp & perks

Compensation - 70k-85k base salary
Flexible Working Hours
Enhanced parental leave
Remote working within the UK only, with optional access to offices in London or Manchester
Annual leave allowance of 26 days, increasing to 30 with tenure and the option to buy additional days
Enhanced sick leave
Private healthcare with our provider, AXA
Regular company and team socials
Uncapped budget for personal development
Share options for all UK employees
Customisable wellness budget and discounts on well-known brands

ATS Keywords

✓ Tailor your resume

Applicant Tracking System Keywords

Tip: use these terms in your resume and cover letter to boost ATS matches.

Hard Skills & Tools

GoTypeScriptJavaScriptPythonAPIsdata modellingtestingversion controlclean codecode quality

Soft Skills

problem solvingownershipcommunicationcollaborationcuriosityenthusiasmsupporting teammatesadaptabilityknowledge sharingresponsibility