Senior Software Engineer (C# / .Net)

LineTenLondon, EnglandOn-siteFull-timeSenior, 5–8 yearsListed 2 weeks ago

Apply now

About this role

What we do

LineTen is on a mission to crack the code on urban delivery. By leading with our values and putting carrier partners first, we are paving the way for better delivery experiences. LineTen is a new approach to delivery with a free carrier API and an operations management platform for shippers. We're building the first global data-driven last-mile network that has the potential to solve industry-wide problems.

We’re hiring a Senior Software Engineer who treats software as a craft, not a checklist. You’ll join a small, high-trust team where ownership is expected, curiosity is encouraged, and outcomes matter more than activity. This is not a ticket-factory role: you’ll be expected to think critically, challenge assumptions, design robust solutions, and take responsibility for their long-term success.

You’ll work across backend services, distributed systems and frontend integrations, with a strong focus on correctness, maintainability and architectural clarity. You’ll also use AI-assisted development tools responsibly, understanding that speed only matters when paired with strong design, testing and review discipline.

How you’ll work

- Operate with high ownership in a low-process environment
- Proactively look for what can be improved rather than waiting for direction
- Value correctness, clarity and maintainability over “it just works”
- Work outside strict role boundaries when needed, without feeding burnout culture
- Communicate technical decisions clearly and push back constructively when required

Core technical skills

- C# / .NET 8+ , Entity Framework Core, async/await, MediatR / CQRS
- Strong understanding of distributed systems : consistency models, event-driven patterns, idempotency, race conditions
- Experience with Redis caching , Azure Blob Storage , and data-modelling trade-offs
- API design : RESTful contracts, versioning, webhooks, long-running operations (202 Accepted patterns)
- Real-time & frontend integration : SignalR / WebSockets, SPA frameworks (Vue / Nuxt or similar), TypeScript

What good looks like

- You leave systems clearer, more correct, and easier to evolve
- Problems are solved at the right level, not patched over
- Trade-offs are explicit and understood
- Other engineers trust your judgement and the quality of your code