AI Engineer – Build AI‑Powered Revenue Platform

About the role

You’ll help build the AI infrastructure and AI‑powered approval workflows for Sequence’s revenue platform, which processes over $1 billion annually. You’ll own end‑to‑end development from design through production, ensuring reliability for business‑critical systems.

Key responsibilities

• Build and own the AI infrastructure platform for reliable software on top of non‑deterministic models, including agentic workflows, prompt iteration, tools, and evaluations.
• Develop flexible AI‑powered approval workflow routing configurable in natural language and turn it into deterministic, auditable business logic.
• Create an intelligent collections agent that executes natural‑language instructions for payment reminders and escalations autonomously.
• Contribute to architecture and design as part of a lean team of 20+ engineers, influencing fundamental systems.
• Ensure AI security, evaluate threat vectors, and treat models as untrusted by default.

Required profile

• Proven experience shipping LLM‑based systems to real customers and handling production failures.
• Designed agentic systems with knowledge of embeddings, memory, tool use, long‑running state, and failure recovery.
• Built evaluation infrastructure (datasets, LLM as judge, prompt regression tests, monitoring) and understands reliability standards.
• Demonstrated ability to write resilient, business‑critical software on top of non‑deterministic models.
• Comfortable with ambiguity, early‑stage ideation, and clear communication.

Required skills

• Kotlin
• Http4k
• Spring Boot
• Exposed
• Result4k
• PostgreSQL
• BigQuery
• Vertex AI
• Langsmith
• Google Cloud Pub/Sub
• Google Cloud Platform
• Terraform
• TypeScript
• React
• Google Cloud Monitoring
• Sentry
• GitHub

What we offer

• Salary: £115,000 – £130,000 per year
• Equity: meaningful share options
• 25 days holiday plus bank holidays
• Modern, flexible pension via Penfold with salary‑sacrifice option
• Visa sponsorship available
• Hybrid work model: three days per week in the London office