Fullstack Product Engineer

Fyxer AI Fullstack Product Engineer

We believe great people are being held back by bad tools.

At Fyxer AI, we're building the next generation of productivity software for people who work in high-velocity, client-facing roles such as consultants, recruiters, real estate agents, and more. These are roles where time is money, but where much of that time is swallowed by low-leverage admin: endless emails, calendar wrangling, meeting notes, and follow-ups.

Fyxer AI eliminates those tasks. We now draft messages in your voice, organise your inbox, schedule your meetings, as well as taking perfect call notes and this is all using AI that works inside the tools you already use (Outlook, Gmail, Zoom).

The key difference? It actually gets used. There's no extra app to learn. No clunky interface. No weird onboarding. Just useful automation, directly where you already work.

We launched in May 2024. Since then:

• We've grown from $0 to $30M+ in ARR in just a few months
• We're serving thousands of paying users
• In February 2025, we closed a $10M Series A round backed by: Marc Benioff (CEO of Salesforce), 20VC, and other world-class investors

And now we're now entering hypergrowth and looking for a few exceptional engineers to help us scale.

The Role: Fullstack Product Engineer

At Fyxer, we don't hire traditional software engineers, we hire Product Engineers.

What's the difference?

Software Engineers typically build what they're told....Product Engineers help figure out what to build in the first place.

This means you'll be deeply involved not just in implementation, but in shaping the product itself: identifying pain points, talking to users, analysing data, and thinking from first principles. You'll have the context, autonomy, and trust to make big decisions and see your work directly impact thousands of users fast.

You won't be handed tickets. You'll help write the roadmap.

What You'll Do

• Take ownership of entire product features from idea to shipped code to user feedback
• Build across the full stack: React on the frontend, TypeScript + GCP on the backend
• Dive into our data to make informed decisions (SQL, BigQuery, Looker)
• Speak to users, analyse behaviour, and shape what gets built next
• Help define and improve engineering practices as we scale
• Collaborate closely with design, product, and leadership all in the same room
• Own technical decisions, tradeoffs, and performance

What We're Looking For

• 3 + years experience shipping production software (ideally at a startup or as a founder)
• Expert-level TypeScript skills and deep understanding of React - You will be an expert on both backend and frontend (but lean more towards the backed)
• Comfortable working across the stack: building APIs, writing SQL, debugging logs, CI/CD
• You've worked in early-stage environments and thrive with high ownership
• You want to solve problems and not just build tickets.
• You enjoy thinking like a Product Manager and delivering great code
• High urgency, high intensity: you move quickly and care deeply about quality
• Strong interest in AI and where it's going

Our Tech Stack

• We're all-in on TypeScript. Our product is backend-heavy, but we care about UX and performance too.
• Frontend: React + TypeScript
• Backend: Google Cloud Functions, Firestore, PubSub, Cloud Storage
• Infra & CI: Github Actions, GCP, Sentry, Google Cloud Logging
• Data: BigQuery, SQL, Looker

Why This Role Is Special

You won't be another engineer on a big team. You'll be one of the foundational builders of the company. That means:

• Real autonomy: you'll make decisions, not wait on them
• Real creativity: we want your ideas, not just your code
• Real impact: you'll see your work hit production and shape how thousands of users experience the product
• Real growth: this isn't a slow-moving company. You'll grow technically and professionally faster than almost anywhere else

This is a rare chance to be at the ground floor of a breakout AI company that's growing fast, is profitable, and has a clear use case that people love.

Interview Process

We keep things fast and focused. No leetcode. No nonsense.

1. Apply with your CV - no cover letter needed but make sure you can demonstrate why you're suitable for this role.
2. Initial intro call - chat with someone from the talent team with a small 5-10 min paired programming challenge (30 mins)
3. Live coding interview - practical and realistic (45 mins)
4. Product case study - explore a feature together (45 mins)
5. Team lunch - meet the people you'll work with every day (60 mins)

Salary and Location

This is a full-time, on-site role in our Central London office (Holborn). We believe high-trust, high-output teams work best when they’re together, especially at this early stage.

For that we will pay you above the market average £90,000–£120,000 + equity + additional benefits

Ready to build?

We're solving a real problem. We're growing fast. We're backed by world-class investors and now we need builders, not just coders.

If you want to move fast, take ownership, and build something people actually use, we'd love to hear from you.