Senior Developer | Java or C# & C/C++ | Financial Data Software House

• Salary: £70,000 circa (depending on experience)
• Location: Fully remote across the UK, with occasional London trips for socials and events (around four a year, at your own cost)
• Team: joining a dev team of six as a senior

They build software that produces financial data to thousands of investors and finance professionals: live prices, charts, and deep company intel, all in one place. It's a small, long-established, profitable business, ISO 27001 certified and London based. You will be working in a development team of six, and you'll be joining as a senior developer.

You'll be working across a wide tech stack, covering Java or C# to client-side JavaScript through to C++ backend that processes hundreds of thousands of market messages a second. The team doesn't just build the product, it keeps it running, so you'll get to know the whole system and take real ownership of keeping it up for customers.

This is genuinely a remote role, not remote-with-strings attached, with the odd trip to London for socials and the occasional get-togethers.

Non-Negotiables

• Java or C# (the platform has both, so being strong in one and happy to learn the other on the job is fine)
• JavaScript, HTML, CSS
• C or C++ exposure (doesn't have to be recent, university or early-career counts)
• Low-level and multi-threaded coding
• SQL (any flavour, MySQL in house)
• DevOps experience, and a genuine willingness to help keep a live service up

What You'll Work With

• A web platform with both Java and C# in the codebase
• A C++ real-time feed handling hundreds of thousands of market messages a second
• A large, long-running store of historical market price data
• A code-review process before anything ships
• Version control moving from CVS to Git this summer
• Self-hosted infrastructure across multiple data centres, on Linux

Nice to Haves

• Team leading or mentoring
• Networking and Linux internals (TCP/IP, protocols, socket programming)
• A degree in computer science or a numerate discipline
• A real interest in financial markets
• Unit testing or structured-testing experience
• Docker and containerisation

Why Join / Projects

The company and management team are very open to change. The stack has been kept deliberately lean over the years and there's now a clear appetite to modernise: moving off CVS onto Git, standing up a proper CI/CD process, and bringing in Docker and containerisation. If you've got opinions on how a small team should ship software in 2026, they want to hear them, and you'll actually see your suggestions land.

There's real engineering waiting too. A major data-format migration for one of their key suppliers should be wrapping up as you arrive, which clears the way for the big one: rewriting the real-time price feeds as multi-threaded code against a new data provider. If you're strong on C++ you could pick that up early. If it's more historic for you, they'll bed you in on something else first and come back to it. In many respects the project work you’ll be given will be shaped around your strengths.

This team owns running the service, not just writing it. There's a separate infrastructure team handling the hardware and networking, but keeping the software up and stable sits with the development team. If you want to write code and hand it over a wall, this isn't the one. If build it, ship it, own it is how you like to work, it's a strong fit.

Employee Benefits

• Fully remote across the UK
• Workplace BUPA private health scheme at heavily reduced cost through payroll
• Company-funded socials several times a year, summer and Christmas parties, all on the company

Urgent role, please apply ASAP for success!

Senior Developer | Java or C# & C/C++ | Financial Data Software House