Looking for full-stack engineer jobs in the UK with visa sponsorship? Apollo Research is hiring a Full-stack Software Engineer to build and scale Watcher, its coding agent security product deployed in production and monitoring billions of AI agent tokens per month. The role is based on-site in London or San Francisco.
Full-Stack Engineer Jobs in the UK: Overview
| Job Title | Full-stack Software Engineer (Product) |
| Employer | Apollo Research |
| Location | London, UK or San Francisco, USA (on-site) |
| Salary | London: £149,000–£195,000; San Francisco: $222,000–$290,000 |
| Job Type | Full-time |
| Experience | 4+ years building production software |
| Visa Sponsorship | Available in both the UK and US |
| Closing Date | Not specified in the available job information |
About the Employer
Apollo Research focuses on risks from AI models evading human oversight, including deceptive alignment and scheming. It works with major AI labs including OpenAI, Anthropic, Google and Meta, and builds Watcher, a coding agent security product used in production by engineering teams at scale-ups and enterprises.
Job Responsibilities
- Design, build and ship Watcher features across the stack: agent hooks, CLI tooling, ingestion and grading pipelines, real-time monitoring UI and an org-wide analytics dashboard
- Own features end to end, from ambiguous requirements to production, including talking to users and making technical decisions
- Build integrations with coding agents, LLM gateways and the wider agent-monitoring ecosystem
- Design and operate backend systems processing large volumes of agent logs in real time
- Own reliability: error handling, observability, logging, metrics and alerting
- Build integrations with the enterprise security stack, including SIEM systems
Requirements
- 4+ years building and operating production software with real users
- Full-stack capability across backend (APIs, data pipelines, databases, cloud infrastructure) and frontend (modern web UI); stack is primarily Python and TypeScript
- High agency and ownership, comfortable making decisions fast with incomplete information
- Heavy prior use of Claude Code, Codex, Cursor or similar tools
- Comfortable with fast-moving startup pace and changing priorities
- Not required: formal AI safety background or management experience
Visa Sponsorship and International Applicants
Apollo Research confirms it sponsors visas in both the UK and the US. Sponsorship is not guaranteed for every role or candidate, but the company states it will work with a successful applicant to find the right visa route, with relocation support and visa fees covered where applicable. This makes it a genuine option for international applicants targeting full-stack engineer jobs in the UK. See more in our Visa Sponsorship Jobs hub.
Salary and Benefits
- London salary £149,000–£195,000; San Francisco salary $222,000–$290,000, plus equity
- Relocation support and visa fees covered where applicable
- Unlimited vacation and unlimited sick leave
- Up to 6 months paid parental leave
- Comprehensive health, dental and vision insurance
- Yearly $1,000 professional development budget
- Strong London and SF salary bands
- Visa sponsorship and relocation support
- High ownership on a live production product
- On-site role
- not remote
- Sponsorship not guaranteed for every candidate
- Fast startup pace expected
How to Apply
Apply directly through Apollo Research’s Lever listing with your CV. A cover letter is not required. The process includes a screening interview, a 3-hour take-home test, three technical interviews and a final interview with the CEO.
Application Tips
- AI tools are allowed on the take-home test, but you’re responsible for the quality of everything you submit
- Practice by building simple monitors for coding agents on your own Claude Code, Cursor or Codex traffic
- No cover letter needed; instead share links to relevant work samples
See more Visa Sponsorship Jobs and Technology Jobs in the UK and beyond.
