Senior Full-Stack Engineer: Real-Time Voice & AI APIs

Hopper Inc.; Greater London; Hybrid; GBP 95,000 - 140,000; Full time

Benefits offered by this job

Competitive salary

Pre-IPO equity

Vitality Health insurance for employee

Smart Pension

Generous parental leave

FlexDesk co-working on demand

Work-from-home stipend

Carrot Cash travel stipend

Unlimited PTO

Entrepreneurial culture

Open communication with leadership

Small teams, massive impact

Job summary

Hopper Inc. is seeking a senior full stack engineer to anchor HTS Assist, owning realtime and voice end-to-end.

You will build across React/TypeScript front ends, Scala and Python services, and cloud infra, with a focus on multi-tenant, scalable architecture and safety/compliance integration. The role emphasizes ownership, mentoring, and shaping the platform from code to customer interactions, with exposure to CPaaS like Twilio and Connect and modern telemetry practices.

Qualifications

• 6+ years of software engineering experience with senior ownership of production systems.
• Real-time systems experience such as voice apps or low-latency products.
• Strong frontend with React/TypeScript and backend with Scala or Python.
• Cloud infrastructure experience on GCP or AWS.
• Proven track record designing and maintaining RESTful APIs and microservices.
• Familiarity with AI coding tools and responsible shipping practices.
• Operating-systems mindset: SLAs, observability, on-call, rollback planning.
• Excellent communication across product, design and ops; able to ship iteratively.

Responsibilities

• Own the voice channel end-to-end including telephony and CPaaS integrations.
• Build features across stack: React front ends, Scala/Python services, and GCP/AWS infra.
• Design for multi-tenant scale via configuration rather than forks.
• Implement safety, compliance, guardrails, and PII redaction points.
• Maintain platform health with observability, alerts, incident response and SLAs.
• Enable go-lives through partner telephony integrations and platform capabilities.
• Mentor teammates and participate in code and architecture reviews.

Tools

React/TypeScript

Scala

Python

GCP

AWS

Twilio

Amazon Connect

WebRTC/SIP

RESTful APIs

Observability

Code reviews

Job description

Hopper Inc. is seeking a senior full stack engineer to anchor HTS Assist, owning realtime and voice end-to-end.

You will build across React/TypeScript front ends, Scala and Python services, and cloud infra, with a focus on multi-tenant, scalable architecture and safety/compliance integration. The role emphasizes ownership, mentoring, and shaping the platform from code to customer interactions, with exposure to CPaaS like Twilio and Connect and modern telemetry practices.