AI Product Engineer

Location: London, UK; hybrid with three days per week in the office

Salary: £115,000–£130,000 per year, plus equity

Company

hirify.global is building an AI-powered revenue platform for finance teams, covering quoting, billing, and revenue recognition.

What you will do

• Build and own AI infrastructure for reliable software on top of non-deterministic models, including agentic workflows, tools, prompt iteration, and evaluations.
• Develop AI-powered approval workflows that convert natural-language customer rules into deterministic and auditable business logic.
• Build an intelligent collections agent that autonomously manages reminders, escalations, and payment-collection workflows.
• Design and ship production backend systems with strong reliability, security, monitoring, and recovery from partial failures.
• Work end-to-end with product, design, and customers to identify, build, ship, and support business-critical features.
• Contribute to architecture and engineering practices as the team grows.

Requirements

• Experience shipping LLM-based systems to real customers and understanding their production failure modes.
• Experience designing agentic systems using components such as embeddings, memory, tool use, long-running state, and failure recovery.
• Experience building evaluation infrastructure, including datasets, LLM-as-judge systems, prompt regression tests, and monitoring.
• Production backend engineering experience and a strong focus on reliability for business-critical systems.
• Understanding of AI security, multi-provider AI tooling, and secure operation of models treated as untrusted by default.
• Clear communication, customer focus, ownership, and comfort working in an ambiguous, fast-moving environment with on-call responsibility.

Nice to have

• Experience with Kotlin, Http4k, Spring Boot, Exposed, Result4k, Postgres, BigQuery, Vertex AI, LangSmith, Google Cloud Pub/Sub, Terraform, TypeScript, or React.
• Experience working in an early-stage product engineering team.

Culture & Benefits

• Small, cross-functional engineering organization with significant ownership and influence over architecture.
• Three office days per week and team lunches on Wednesdays.
• Meaningful share options.
• 25 days of holiday plus bank holidays.
• Flexible pension through Penfold with salary sacrifice available.
• Visa sponsorship available.

Hiring process

• The process typically takes approximately two weeks from start to finish.