Senior Fullstack Engineer

£450–550 per day

6 months

Outside IR35

Hybrid – 2 days per week on site (London)

We’re supporting a high-growth, AI-driven product business building a scalable platform from the ground up. They operate as a small, high-calibre team with high standards, low bureaucracy, and real ownership. They’re looking for a Senior Fullstack Engineer (back end leaning) to take responsibility for core backend systems and help shape product direction in fast-moving environment.

This is a role for someone who is comfortable building without perfect specs and takes initiative naturally.

Requirements

• Strong Node.js and GraphQL (NestJS) experience
• PostgreSQL, Prisma, and solid data structures / OOP fundamentals
• Experience building high-concurrency, event-driven systems
• GCP experience (Terraform desirable)
• Experience working with AI/LLMs in production environments
• Strong focus on system reliability (monitoring, alerting, logging, testing, incident-aware design)
• Demonstrated ownership of features or systems end-to-end, with the ability to operate independently
• Comfortable making progress in environments with evolving or incomplete requirements
• Pragmatic approach to delivery — able to balance speed with long-term maintainability
• Proven ability to operate effectively under pressure or shifting priorities
• Ideally has built, launched, or scaled a product, startup, or meaningful side project