Senior Product Engineer (React/Typescript) - AI Startup

Fyxer Limited; London; On-site; GBP 95,000 - 115,000; Full time

Job summary

Fyxer Limited is seeking a top-tier product-minded engineer to join their team in London. This role offers deep ownership of product development in a fast-paced startup environment focusing on AI productivity tools. Candidates should have extensive experience in React and TypeScript, along with a passion for shaping product and engineering culture.

Benefits

Significant equity

Fast growth and autonomy

High-caliber team culture

Qualifications

• 4+ years of hands-on experience with React and TypeScript.
• Experience in early-stage companies or startup environments.
• Ability to work across both frontend and backend systems.

Responsibilities

• Build features that improve the product based on usage data.
• Architect clean and scalable systems.
• Participate in all stages of product development, from ideation to deployment.

Skills

React

TypeScript

Full-stack development

Tools

Google Cloud

BigQuery

Sentry

GitHub Actions

Job description

About Us

At Fyxer AI, we’re building an AI productivity tool that eliminates the admin burden for client-facing professionals - think real estate agents, consultants, recruiters, people who live in their inboxes.

Our product handles the heavy lifting: sorting emails, drafting replies in your tone of voice, taking smart meeting notes, and surfacing next steps.
It integrates directly with Gmail, Outlook, and Zoom with no onboarding, no new tabs. Just high-utility software that gets used.

Since launching in May 2024, we’ve gone from $0 to $11M ARR, raised a $10M Series A from top-tier investors (including Marc Benioff and 20VC), and are scaling fast toward $50M.

What You'll Be Building

We're not looking for ticket-takers. We're hiring the top % of product-minded engineers who want full ownership of what they ship from shaping the roadmap to writing world-class code.

You’ll be part of a small, senior engineering team trusted to:

• Dive deep into usage data and customer feedback
• Propose and build features that meaningfully improve the product
• Architect clean, scalable systems
• Move fast, ship often, and take pride in quality
  
  

You Might Be a Fit If:

• You’re a React & TypeScript expert with deep technical hands-on experience of more than 4+ years
• You’ve worked in early-stage companies (sub-100 people), or you've been a founder
  You care about product as much as code and you're eager to explore customer problems, not just implement specs
• You’re full-stack enough to jump into backend APIs, write SQL queries, and handle devops basics
  You thrive in high intensity, high ownership environments
• You're excited about AI, not just as a buzzword but for its practical power to transform work
  
  

Our Stack:

• Frontend: React, TypeScript
• Backend: TypeScript on Google Cloud (Cloud Functions, Firestore, Pub/Sub)
• Data: BigQuery, Looker
• Monitoring: Sentry, GCP Logging
• DevOps & CI/CD: GitHub Actions
  
  

What You’ll Get:

• £95k–£115k + significant equity & other benefits
• Deep ownership of a fast-growing product
• A team of high-calibre, mission-driven builders
• The opportunity to shape product and engineering culture early
• Fast growth, real autonomy, and zero bureaucracy

Interview Process

• Submit your CV (no cover letter needed)
• Intro call with someone from the team with an initial paired programming exercise (30 mins total)
• Product case study (45 mins)
• Live coding interview (45 mins)
• Team lunch and culture fit conversation (60 mins)
  
  

We’re building a team of the sharpest product engineers in London. If you want to move fast, ship boldly, and build something that truly helps people, let’s talk.