Role Overview
Seeking a Senior Backend‑leaning Software Engineer to join Simon's team, working within the origination and customer onboarding domain. This role focuses heavily on backend systems, operating across both legacy .NET Framework 4.8 and modern .NET 8 services. The engineer will support critical customer onboarding APIs, contribute to modernisation efforts, and own work end‑to‑end in a squad with limited capacity, requiring strong independence and technical maturity. Light UI work may occasionally be required.
Team Context & Ways of Working
Backend‑heavy engineering squad
Work covers customer origination, onboarding flows, and related microservices
Engineers operate with high autonomy due to capacity constraints
Strong emphasis on reliability, stability, and risk‑aware delivery
Collaborative environment but suited to someone confident working independently
Tech Focus
Backend (.NET)
.NET Framework 4.8 (migration + maintenance work)
.NET 8 APIs (already live and actively developed)
Legacy API patterns and libraries as well as modern cloud‑friendly .NET 8 services
Databases
mySQL (schema knowledge required)
SQL Server
PostgresNot required immediately, but likely useful in future work
Other Technologies
Light frontend/UI tasks (as needed)
API test automation
Playwright (nice to have)
Core Responsibilities
Design, build, and maintain backend services across both modern and legacy .NET stacks
Participate in migration initiatives from .NET Framework to .NET 8
Work directly with SQL databases, including schema updates, optimisations, and data modelling
Build robust, well‑tested APIs that support customer onboarding flows
Troubleshoot, maintain, and enhance existing legacy APIs and services
Integrate backend systems with internal frontends and other platform services
Work independently to deliver features in a capacity‑constrained environment
Ensure compliance with risk, security, and reliability expectations
Required Experience
Strong backend engineering experience with .NET
Comfortable working with legacy APIs and modern .NET 8
Hands‑on experience with SQL databases and schema design
Ability to work autonomously and make sound technical decisions
Strong understanding of API design, distributed systems, and backend architecture fundamentals
Experience navigating legacy codebases while contributing to modernisation efforts
Nice to Have
Experience with automated API testing (Playwright)
Background working in regulated/financial environments
Familiarity with event‑driven or message‑based patterns
Experience with microservices architecture and migrations