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Senior Full Stack Developer

Spliit LtdManchester Science Park, Manchester🇬🇧United KingdomPosted 17 Oct 2026

Why This Role Stands Out

This hybrid Senior Full Stack Developer role at Spliit Ltd offers you the chance to own features end-to-end, tackling complex FinTech challenges in payments and financial correctness. You'll thrive here if you're passionate about meticulous financial modeling and building resilient systems, with significant influence over architecture in a high-trust engineering environment. Embrace this opportunity to grow your skills and make a tangible impact on a cutting-edge platform.

Quick Overview

Salary
£65k - £85k/yr
Seniority
Mid Senior
Employment type
Full Time
Work mode
Hybrid
Location
Manchester Science Park, Manchester, United Kingdom
Posted
22 hours ago
SQLSQL ServerExpoAzureC#.NETReactReact NativeTypeScript

Job Description

About us

We're a Manchester-based FinTech building a smarter way for tenants to pay rent. Our platform pays landlords the full rent on time and collects smaller instalments from tenants via Open Banking Variable Recurring Payments (VRP). We're a small, high-trust engineering team solving genuinely hard problems in payments, credit, and financial correctness — where getting the maths and the money movement exactly right matters.

The role

We're looking for a Senior Full Stack Developer to own features end-to-end across our .NET backend and React Native mobile client. You'll work close to the domain — instalment maths, double-entry ledgers, scheduled money movement, and third-party integrations with banking and identity providers. This is a hands-on senior role with real ownership and influence over architecture.


What you'll work with

  • Backend: .NET 10 / C#, EF Core (SQL Server), a service-oriented solution with clean domain boundaries
  • Async & messaging: MassTransit, background workers, durable/idempotent scheduled jobs
  • Cloud & platform: Azure, .NET Aspire, containerised services
  • Mobile: Expo / React Native (TypeScript)
  • Integrations: Open Banking, VRP, BaaS, identity verification, credit decisioning
  • Practices: ADR-driven architecture, EF Core migrations, automated testing (MSTest, NSubstitute, FluentAssertions)

What you'll do

  • Design and ship features spanning the C# backend and the React Native app
  • Model financial domains carefully — money, fees, timing differences, ledgers — where precision is non-negotiable
  • Build resilient, idempotent background processing for payment execution and scheduling
  • Integrate with external banking, payments, and identity providers
  • Contribute to architectural decisions

What we are looking for

  • Strong commercial experience with C# / .NET and modern TypeScript
  • Solid EF Core / relational database skills (SQL Server ideal)
  • Experience building and consuming APIs, and working with asynchronous/message-based systems
  • React Native (Expo) experience, or strong React skills and appetite to work across mobile
  • A pragmatic, quality-first mindset — you care about correctness, testing, and clear design
  • Bonus: FinTech / payments / Open Banking experience, cloud (Azure), event-driven architecture

Experience:

  • C#: 5 years (required)
  • React Native: 2 years (required)

Work authorisation:

  • United Kingdom (required)

Work Location: Hybrid remote in Manchester


  • £65k–£85k salary depending on experience
  • Hybrid working from our Manchester office
  • 25 days holiday + bank holidays
  • Pension, and the chance to shape a product (and a team) from an early stage
  • Meaningful ownership and a direct line to the impact of your work
  • Sound like you? Apply with your CV and a short note on something you've built that you're proud of.

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