Lead Frontend Engineer

Remote (UK-based) | Full-Time

About Us

Reactive Markets is the 2026 OTC Trading Platform of the Year (Risk.net). Our network handles over $50 billion in daily trading volumes across FX, Equities, and Cryptocurrency, connecting 40+ of the world's leading liquidity providers. We build trading systems that operate at the edge of what's technically possible — where nanoseconds matter and a dropped message costs real money. Our engineering team is small, senior, and deeply invested in the craft of building cutting edge, reliable, high-performance systems.

The Role

We're looking for a hands-on engineering leader to own our Frontend team — the full-stack application engineers who build the trading platform our clients use. Despite the "frontend" name, this is not a UI-only role. The team works across the whole application stack in TypeScript and Rust, from the trader-facing interfaces down to the services behind them. It's distinct from our Backend team, who own the low-latency C++/Go trading engine.

This is a player-coach role. You'll still write code, review the work that matters, and make the architectural calls that keep the platform fast and maintainable — while owning the team's delivery, its standards, and the development of the engineers in it. The role only works if you can hold two things at once: hands on the platform (credible to your engineers because you understand the work) and off the critical path (leading with depth and raising the team up, so nothing depends on you alone at the keyboard).

You'd be the clear owner of this team — responsibility for it is currently shared informally across our CDO, our Head of Technical Delivery, and the most senior engineer. Part of the job is to take that on, close out the informal cover, and build a team that runs under its own steam. This is not a role where you write code and throw it over a wall: our engineers own the full lifecycle, and when something breaks, you lead the team that investigates and fixes it.

Occasional hours outside the normal working day are required for production releases, scheduled maintenance windows, and Level 3 support during critical incidents. We keep this to a minimum and recognise the commitment — but owning a production trading platform means being there when it matters.

What You'll Work On

• Driving the technical direction of the frontend application stack — architecture, standards, and the trade-offs that keep the platform fast and maintainable
• Hands-on TypeScript and Rust — building and reviewing the most critical or complex work yourself
• Real-time, data-dense trading interfaces across FX, Equities, and Cryptocurrency, and the application services behind them
• Owning code quality across the team through review, design sessions, and the standards you set and enforce
• Developing the engineers on the team — technical craft and the non-coding skills that let people scale
• Shaping the roadmap with the CTO, CDO, Technical Delivery, and Client facing teams, and turning priorities into delivered software
• Ensuring the team owns its Level 3 support, observability, and operational readiness — reliability is not optional

What We Need

• Strong full-stack engineering background with deep TypeScript / JavaScript (ES6+) (5+ years, including time leading or setting technical direction for a team)
• Familiarity with React and reactive state management (RX, MobX, or similar)
• Working knowledge of Rust, or the clear appetite and ability to get there — it's part of our stack
• Solid grasp of distributed systems, API design, and real-time data (REST, WebSockets, network protocols) — you understand what it takes to build software that's fast and reliable under load
• Able to make and defend architectural decisions, and explain the trade-offs to engineers and non-technical stakeholders alike
• Experience in financial services or trading technology

• You lead by example. You write code, review designs, and hold the highest standards. Engineers respect a lead who understands the work, not one who manages it from a distance
• You build strength across the team. You know when to be hands-on and when to step back. You lead with depth and raise the others up, rather than being the single point of failure
• You own it. You take responsibility for the team's delivery, quality, and production reliability — not just your own output. When something breaks, you lead the investigation and fix
• You develop people. You invest time in mentoring and growing the team, and you can point to engineers who are better for having worked with you
• You're direct and honest. You give specific, timely feedback, and you hold a quality line without becoming a bottleneck
• You communicate. We're a distributed team across multiple time zones. Clear, proactive communication — especially during incidents and in stakeholder updates — is essential
• You embrace AI tooling. We use AI tools (Claude, Gemini) to amplify our engineering capability — from code review and debugging to incident investigation and documentation

What You Get

• Real problems — trading systems where performance is measured in microseconds, not user clicks
• An excellent team — senior engineers who care about craft, collaborate openly, and hold each other to high standards
• Ownership — small teams, clear accountability, direct impact on the platform and our clients
• Competitive package — up to 30 days leave + bank holidays, private health insurance, pension, life insurance, dental/optical cashback, cycle to work, socials and offsites
• Remote-friendly — work from home with flexibility. We trust our people to deliver
• Sustainable pace — we work hard, but we don't burn people out. Balance is how we stay sharp
• Growth — career progression to senior roles, performance specialisation, or technical leadership. We invest in people who invest in us

We believe in transparency, honest feedback, and writing things down. We celebrate delivery, not activity. We frame AI as empowering people — removing toil, amplifying capability, enabling higher-value work. We aim to build systems that don't depend on the heroics of individuals to maintain and support — systems and processes that are resilient, documented, and sustainable.

Our Hiring Process

We keep our process focused and respectful of your time. Our process follows three stages.

• Stage 1: Initial Conversation with Talent Acquisition - Format: Video call, ~30-45 minutes
• Stage 2: Hiring Manager Conversation with the relevant team lead or hiring manager - Format: Video call, ~60 minutes
• Stage 3: Technical Interview with two members of the relevant engineering team - Format: Video call, interactive session, ~60 minutes

What to expect in each stage will be explained by Talent Acquisition if you're invited to interview. Throughout the process, we aim to keep momentum with no unnecessary delays between stages, and feedback typically comes within a few business days.

How to Apply

Please apply directly via this job posting — all applications, including those submitted via LinkedIn, are managed through our applicant tracking system, so you'll always land in the same place regardless of where you found this role.

Right to Work: Candidates must have the existing right to work in the UK. We are not currently able to offer visa sponsorship for this role.

Equal Opportunities: Reactive Markets is an equal opportunities employer. We welcome applications from all qualified candidates regardless of age, disability, gender reassignment, marriage or civil partnership, pregnancy or maternity, race, religion or belief, sex, or sexual orientation.

Reasonable Adjustments: If you need any adjustments or support during the application or interview process, please let us know — we're happy to accommodate.

Data Protection: By applying, you consent to Reactive Markets processing your personal data for recruitment purposes.