CRO Frontend Engineer - React/Typescript

Fyxer Limited; City Of London; On-site; GBP 70,000 - 90,000; Full time

Job summary

A rapidly growing tech company in London is seeking a Growth Engineer to drive product-led growth initiatives. The role involves independent ownership of projects, data analysis to improve customer journeys, and a strong understanding of TypeScript and React. Join a passionate team working on innovative AI productivity tools that aim to automate administrative burdens for client-facing roles.

Qualifications

• Thorough understanding of TypeScript and React.
• Core growth skills including data analysis and UX design.
• Ability to function as a full-stack engineer with DevOps knowledge.

Responsibilities

• Own and implement growth experiments to improve product-led growth.
• Analyze data and prioritize backlog for product improvements.
• Work independently alongside other growth engineers.

Skills

Data analysis

UX design

Product development

TypeScript

React

SQL

Job description

The basics

• This role pays £70k–£90k/year + equity.
• Kameron, our Senior Growth Engineer, is the hiring manager.
• We work from our office in Chancery Lane, London, Monday to Thursday. Fridays are work-from-home days.

What are we building?

Great people are working on overdrive to do a great job, but are held back because their inbox is failing them.

We’re building an AI Productivity tool that eliminates the admin burden for people who work client facing roles. Think real estate, consultants, recruiters - people who spend hours on emails, scheduling, and follow ups. Fyxer AI simplifies these tasks by organizing your inbox, drafting replies in your own voice, and taking crisp meeting notes.

The best part? Unlike a lot of other AI tools, ours actually gets used.

We’ve built the product so it requires little set up & nothing extra for users to learn. It works directly inside Outlook, Gmail, & Zoom.

How’s it going?

Since our launch in May 2024, we’ve grown from $0 to $8 million in revenue, serving thousands of paying users. In February 2025, we raised a $10 million Series A to accelerate our path to $50 million in revenue—backed by top-tier investors including Marc Benioff (CEO of Salesforce) and 20VC.

We spent Q4 2024 in San Francisco at HF0, the best AI startup accelerator in the world, learning from experts like the CEO of Instacart, Head of Applied Research at OpenAI and the Co-founder of Snowflake. We're now at the stage of hypergrowth and are looking for the best of the best.

What we value:

We believe small, passionate teams outperform big, unfocused ones every time. That's why we're highly selective about who joins us. We're looking for people who bring intensity, creativity, and genuine care to their work.

You'll take on meaningful responsibilities from day one, with opportunities to grow faster than at most companies. We trust our team with real ownership and autonomy because that's how the best work happens.

We hire T-shaped individuals who can own the entire product development lifecycle. Instead of just being given tickets to implement, you’ll own a whole product: shaping the roadmap by thinking from first principles, looking at usage data, and speaking to customers—then architecting and implementing your ideas.

What will I do?

• In short, you'll be expected to come up with and entirely own implementing your experiment ideas to improve product-led growth at Fyxer AI.
• Although you'll be working alongside other growth engineers, this role requires a lot of independence and self-management to come up with ideas and execute them.
• You'll use data from Metabase, BigQuery, and PostHog to generate new ideas, analyse your experiments, and prioritise your backlog.

What does our ideal hire look like?

Must have:

• Thorough understanding of TypeScript and React.
• Can function as a full-stack engineer (leaning heavily towards front-end development), working on both client and server-side code, answering data questions using SQL, and contributing to DevOps and CI/CD processes.
• Core growth skills including data analysis, UX design, and product development, combined with a passion for marketing and conversion psychology to ideate and build high-impact experiments.
• A sense of urgency and intensity in your work.

Ideal:

• Worked at an early-stage tech company as an engineer (<100 people), or been a founder.
• Keen interest in LLMs, workflow automation, and AI agents.
• Previous experience as a growth engineer or as a software engineer in a growth team, or you’ve demonstrated through self-driven work any of the following: optimising customer journeys, building virality/seat expansion/referrals, or building revenue operations infrastructure.
• Knowledge of the typical B2B SaaS growth/revops stack—experimentation, CRM, segmentation tools.

Our tech stack

Broadly, we use a fairly typical serverless Typescript stack. It’s not a requirement to have worked with every tool in this stack, but the more the better:

• Typescript for all production code
• Firestore as our production database
• Firebase Auth as our auth system
• Backend deployed on Firebase Functions, and making use of PubSub and Cloud Storage
• React frontend, using ShadCN for components, TailwindCSS for styling, React Query for state management
• Posthog for frontend analytics (events, sessions, feature flags, experiments)
• BigQuery as our data warehouse, with Metabase for data visualization. Production data and Posthog events both stream into it so data is in one place.
• Sentry and Google Cloud Logging for monitoring
• Github Actions for CI/CD

The application process

1. Submit your CV (no need for a cover letter).
2. Initial call with someone from the Fyxer AI team to review your experience and motivation (20-30 mins).
3. Experience interview with one of our growth engineers (30 mins).
4. Practical interview (1hr):
1. Wireframe an experiment and talk us through your thinking (30 mins).
2. Live coding exercise (30 mins).
5. Meet Richard, CEO (30 mins).