Founding Engineer (Backend)

Remotestar; Cambourne; On-site; GBP 106,000 - 159,000; Full time

Job summary

Remotestar seeks a backend-leaning Founding Engineer to help build core infrastructure for AI agents in an early-stage setting. 0–7 years of production software experience and a track record at FAANG or well-known VC-backed startups (Series A+) are desired.

You will own projects end-to-end—from scoping customer requirements through system design to production rollout—while shaping API design and scalable backend systems in a hands-on role.

Qualifications

• Strong TypeScript proficiency.
• Experience shipping features end-to-end in production.
• CS degree or technical degree from a top engineering school.

Responsibilities

• Build and design APIs and backend infrastructure that AI agents use to communicate, authenticate, and operate.
• Own 0→1 projects end-to-end—from scoping customer requirements through system design to production rollout (e.g., IMAP integration, usage-based pricing systems).
• Work across the full stack (~80% backend, ~20% frontend/other), touching distributed systems, databases, and developer tooling.
• Be a frontline point of contact for customer feedback and support enterprise deployments.

Skills

TypeScript

Education

CS degree

Job description

Location: San Francisco, CA (On-site, 5 days/week)

Role

We're looking for a backend-leaning Founding Engineer (0–7 years experience) who has shipped production software at a pedigreed company — FAANG, high-growth VC-backed startups (Series A+), or equivalent. You'll own projects end-to-end in a fast-moving, early-stage environment and help shape the core infrastructure that AI agents use to communicate and operate in the real world.

What You’ll Do

• Build and design APIs and backend infrastructure that AI agents use to communicate, authenticate, and operate
• Own 0→1 projects end-to-end — from scoping customer requirements through system design to production rollout (e.g., IMAP integration, usage-based pricing systems)
• Work across the full stack (~80% backend, ~20% frontend/other), touching distributed systems, databases, and developer tooling

Proactively pitch ideas — you're expected to bring product and growth thinking, not just execute tickets

• Be a frontline point of contact for customer feedback and support enterprise deployments
• Write clear, maintainable code and documentation while processing hundreds of thousands of emails per day

What We’re Looking For

• Strong proficiency in TypeScript or modern equivalent frameworks
• Experience at a FAANG or well-known VC-backed startup (Series A+)
• Deep backend fundamentals: REST API design, system design, server-side architecture
• Track record of shipping and owning features from 0→1 in production with real users
• CS or technical degree from a top engineering school (especially for new grads)
• High agency — you bring ideas and drive execution without needing scope handed to you
• Strong communicator of tradeoffs, blockers, and technical decisions
• Must be based in or willing to relocate to San Francisco (on-site 5 days/week)

Bonus Points

• Experience with email, messaging, or protocol-heavy systems (SMTP, IMAP, OAuth)
• Exposure to cloud infrastructure, distributed systems, or developer tooling — especially in AI/LLM or agent workflows
• Prior founding, fellowship, or 0-to-1 building experience
• Evidence of doing hard things outside of engineering — competitive athletics, self-directed projects, anything showing grit and agency