Senior Full Stack Engineer (Realtime & Voice) - IT Role in the UK at Hopper
Hopper is seeking a Senior Full Stack Engineer (Realtime & Voice) to join its IT team in the UK on a senior level. In this role, you will anchor HTS Assist—Hopper's agentic AI assistant for travel—owning the realtime and voice layer end to end. You will build across React and TypeScript front ends, Scala and Python services, and cloud infrastructure on GCP, helping resolve flight changes, cancellations, refunds, and bookings over chat and voice for major travel brands.
Core Responsibilities
- Own the voice channel end to end, including telephony and CPaaS integrations like Twilio and Amazon Connect, streaming STT/TTS pipelines, realtime model orchestration, and latency budgets.
- Build product features across the stack, design for multi-tenant scale using configuration rather than forks, and implement safety and compliance plumbing such as PII redaction and guardrails.
- Maintain revenue-critical deployments through observability, alerting, incident response, and SLA performance, while raising the engineering bar via code reviews and mentoring.
Requirements and Background
- Master's degree and 6+ years of software engineering experience with senior-level ownership of production systems and full-stack range.
- Hands-on realtime systems experience (voice applications, WebRTC/SIP, streaming media, or low-latency products).
- Strength in React and TypeScript, depth in Scala or another JVM language and/or Python, and cloud infrastructure experience on GCP or AWS.
- Track record designing and maintaining RESTful APIs, microservices, or event-driven systems, alongside familiarity with AI coding tools and an operable-systems mindset.
Perks include pre-IPO equity packages, 100% employee coverage for a group insurance plan through Vitality Health, Smart Pension contributions, generous parental leave, a work-from-home stipend, FlexDesk access, Carrot Cash travel stipend, and unlimited PTO. The salary listed is rs 100.