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Complexio

Lead Full-Stack Engineer

Posted 4 Days Ago
In-Office or Remote
3 Locations
Senior level
In-Office or Remote
3 Locations
Senior level
Lead the development of an enterprise AI knowledge assistant's frontend, focusing on user experience, real-time data interfaces, and product direction.
The summary above was generated by AI

Complexio is building Stevie — an enterprise AI knowledge assistant that gives executives and operators a complete view of their organization through knowledge graphs. Our customers are large maritime shipping companies managing hundreds of vessels, thousands of daily emails, and complex commercial operations.

We're looking for a Senior or Lead Frontend Engineer to own Stevie's frontend. The interface is the product — it determines whether enterprise customers trust the intelligence, get value quickly, and come back. You'll shape all of that.

Why This Role

   Enterprise AI UX is unsolved. You won't copy patterns — you'll create them. Citations from knowledge graphs, streaming AI responses that feel trustworthy, confidence indicators on operational intelligence.

   You own the full frontend. No separate frontend team. You are it — with real influence on product direction and architectural decisions.

   Flat org, real impact. Domain owners have authority. Engineering decisions are made by engineers, not managers.

You'll own the full frontend — conversational AI interfaces, content feeds, document generation, collaborative features. The product is evolving fast and you'll shape what gets built and how.


Requirements

Must-haves

   5+ years of frontend experience in production. You understand rendering models, performance characteristics, and architectural patterns deeply.

  •    Strong product sense. You push back when the UX doesn't make sense. You've shipped real user-facing products.
  •    Real-time/streaming UI experience. WebSockets, SSE, or similar live data patterns.
  •    Comfort with ambiguity. You take vague problems and turn them into concrete frontend solutions.
  •    You ship. End-to-end — prototype to production to iteration on feedback.

Strong signals

  •    Enterprise/B2B SaaS. You know the difference between consumer UX and building for a CFO who needs to trust a number.
  •    AI product experience. Latency UX, citation rendering, hallucination presentation.
  •    Design sensibility. Polished interfaces without a designer in the room.
  •    Backend literacy. You can read a REST API and collaborate with backend engineers on data contracts.
  •    Startup experience. Small teams, multiple hats, fast without cutting corners.

How We Work

  •    Direct communication. Honest feedback, hard questions, no hiding behind process.
  •    Ownership over tasks. You're asked what you shipped and learned, not to fill out status reports.
  •    Speed with quality. We ship fast because we scope well. Customer feedback cycles are weeks, not quarters.
  •    AI-augmented workflow. We use AI tools extensively and expect you to be comfortable with AI-assisted development.

Top Skills

Rest Api
Sse
Websockets

Complexio London, England Office

First Floor, 5 Fleet Place United Kingdom, London, United Kingdom, EC4M 7RD

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