Senior C++ Developer (Hybrid, UK-Based)

Senior C++ Developer (Hybrid, UK-Based)

Location: London

Salary: £80,000 - £100,000 + EMI Share Options + Private Medical Insurance

Vacancy Type: Full-time, Permanent

We take care of time, so our customers don t have to.

At Hoptroff, we build nanosecond-accurate, software-driven timing systems used by global investment banks, telecoms operators, and broadcasters - including the MiFID II-compliant trade timestamping that financial regulators depend on. When microseconds aren t tight enough and milliseconds are an eternity, our software is what s keeping the world in sync.

We re entering an exciting phase of growth and looking for a Senior C++ Developer to join our small, high-calibre engineering team. You ll write modern C++ (C+ or later) at the heart of our Linux-based clock and time synchronisation platform - tight, performance-sensitive code where jitter is measured in nanoseconds and correctness is non-negotiable. You ll own significant components of the platform, contribute to architecture, and work closely alongside a junior developer and a contractor on a tight, collaborative team.

The Role

Reporting to the Software Development Manager, you ll lead the design, development, and optimisation of C++ software within our Linux-based timing systems. Day to day, you will:

• Design, build, and optimise low-latency, high-precision C++ at the heart of our timing products - code where performance, determinism, and jitter really matter
• Make architectural decisions on systems that have to be correct, fast, and observable in production - balancing maintainability with the hard real-time constraints of precision timing
• Develop online and offline tooling to support time synchronisation and system monitoring
• Build and maintain automated test cases using Python-based system test frameworks
• Provide senior-level technical input across product, QA, hardware, and commercial conversations
• Share knowledge, review code, and support the development of our junior C++ developer
• Help shape engineering standards, tooling, and processes

Essential Experience

• Extensive professional experience writing modern C++ in production - fluent in modern C++ idioms and confident with C+/23 features such as concepts, ranges, coroutines, and constant expressions (constexpr/consteval)
• A track record of delivering low-latency, performance-sensitive systems on Linux - production code where determinism, throughput, and tail latency matter
• Strong computer science fundamentals: data structures, algorithms, concurrency, performance optimisation
• Demonstrable ability to design software architecture and make sound technical trade-offs
• Strong debugging and profiling skills (perf, valgrind, sanitizers, flame graphs) - you ve cared about cache lines, lock contention, jitter, and tail latency, not just correctness
• Confident with Git, CI/CD pipelines, modern build tooling (CMake), and automated testing frameworks
• Clear technical communicator - you can explain trade-offs to engineers and non-engineers alike

Nice to Have

• Linux networking experience (sockets, networking concepts and standard tooling)
• Experience interacting with hardware on Linux (device drivers, system interfaces, low-level I/O)
• Low-level Windows systems development (Windows APIs, system services, platform-specific debugging)
• PostgreSQL or other relational database experience
• Python and/or Go (Golang) for tooling, automation, or supporting services
• Familiarity with time synchronisation protocols such as PTP or NTP
• Open-source contributions or evidence of staying current with the C++ standard
• Open to integrating AI tools where they add value

What We Offer

• Salary of £80,000 - £100,000, depending on experience
• EMI Share Options
• Private Medical Insurance
• Hybrid working - 2 days per week at our London (Shoreditch) office, with regular team events
• Based at a Shoreditch FinTech incubator - a thriving community of like-minded businesses with a full social calendar, networking opportunities, and (importantly) dog-friendly
• Your code will sit underneath MiFID II-compliant trade timestamps at major banks, broadcast sync at tier-1 broadcasters, and timing infrastructure at telecoms operators - tangible, high-stakes impact at global scale
• A team that invests in modern tooling and continuous learning

To Apply

If you feel you are a suitable candidate and would like to work for HopTroff, please do not hesitate to apply.