IT & Software

Senior Full-Stack Engineer

Plan:it

London · England · United Kingdom

London / hybrid, 3–4 days per week in the office

This is a rare opportunity. Chance to join an early-stage startup as engineer #4. Autonomy, responsibility and working with cutting edge AI.

Company

A well-funded, early-stage startup building a genuinely AI-native product. AI at the core, with agentic systems already running in production. Small team, high standards, and an awesome team culture.

The Role

This is a senior full-stack engineering role for someone who thinks in systems, not just tickets. You'll build features end-to-end, maintain what you ship, and raise the quality bar across the codebase. The team is small, so you'll touch most parts of the stack most weeks - and you'll be expected to operate with minimal oversight.

Key responsibilities

  • Build features end-to-end
  • Spot and fix rough edges before users do
  • Build directly on top of agentic systems
  • Use AI tooling daily to plan, write, review, and ship code faster

Stack

TypeScript, React, AWS, GCP. Agentic systems and LLM-powered features already in production.

You'll be a good fit if you…

  • Early-stage or startup experience is a must!
  • Have 6+ years of professional software engineering experience - ideally with real ownership
  • Are genuinely comfortable across the full stack - UI, API, and database
  • Already use AI tooling daily - coding assistants, agents, or similar. This is a must
  • Have hands-on experience with agentic systems or LLM-powered features in production (nice to have)
  • Are high agency you find work that needs doing and do it

The Package

  • Up to £130k base (DoE) + equity
  • 30 days holiday
  • London - hybrid, 3–4 days per week in the office

Interview Process

  • On-site final and meet the team

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Reference: WJ-766_21450080

Apply now

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