Front End Design Engineer in London

About Seamflow

Every plane, medical device, lift, battery and building has to be tested, inspected and certified before it reaches the world. It's the invisible layer that keeps the physical economy safe, and it still runs on Word documents, PDFs, spreadsheets and email. Seamflow is the software layer for that industry. We build AI-powered workflows for certification bodies, notified bodies and inspection companies: scheduling and resource planning, technical review, conformity assessment, field inspection, and document intelligence over messy real-world files.

Where we are:

• Live in production inside some of the largest enterprises in the industry
• $4.5M seed, 14x oversubscribed, co-led by Northzone and Initialized Capital, the funds behind Spotify, Klarna, Coinbase and Reddit.
• Angels include Charlie Songhurst and Mario Götze.

Demand is outstripping what we can build. That's the reason this role exists.

The team

Most of our engineers were olympiad medallists in maths, physics or informatics before they were engineers. The team has come to us from Google, Amazon, X, Yandex, McKinsey and Bain, and from founding-engineer seats at startups that went on to multi-billion-dollar valuations. We hire against a very high bar, and this role exists to raise it further.

The role

A Front End Design Engineer thinks in finished interfaces, not mockups or components in isolation. A technical reviewer at a notified body spends their day inside a 400-page technical file, cross-referencing clauses, checking test reports against standards, and deciding whether a medical device is safe to sell. Today they do that in Word, Acrobat and a spreadsheet someone built in 2011. The interface they use decides how fast they work and whether they trust the AI sitting next to them.

You own that interface. Layout, typography, interaction, motion, the design system underneath it, and the React that ships it. You decide how a reviewer sees a finding, how they correct a model that got it wrong, and how a hundred fields of dense regulatory data become something a person can actually read. You sketch it, build it, ship it, then sit next to someone using it and find out what you got wrong. You'll ship to production in your first week.

What we're looking for

We care far more about taste and engineering strength than about matching a list of tools. If you're excellent, we'll hire you whether you've spent the last three years in React, Svelte, Vue or something we haven't heard of. Our stack is learnable in a fortnight. Judgement, craft and speed are not.

What we're actually screening for:

• You've designed and built an interface that real people used every day. Not a Dribbble shot, not a component library nobody adopted. Something that shipped, got used, and got better.
• You have taste, and you can defend it. Typography, spacing, motion, hierarchy. You notice when something is a few pixels off and you can explain why it matters.
• You build the whole thing. Design, frontend, the state and data it sits on. You don't hand the code to someone else once the Figma is done, and you don't hand the design to someone else once the code is.
• You can design for density. Expert users, complex workflows, hundreds of fields on a screen. Making that clear is much harder than making a landing page beautiful.
• You go to the source. You'll watch a technical reviewer work through a real file, and you'll design for what they actually do rather than what the process diagram says.

Signals we like, none of them required:

• Design engineering or front-end roles at somewhere like Linear, Vercel, Notion or Figma.
• A design system you built and maintained.
• Work on interfaces where people review or correct AI output.
• Founder or ex-founder, founding team experience, EF / YC / Antler, early or stealth-stage startup.

This is probably not for you if

• You want a strict boundary between work and life. We run one of the most ambitious startup cultures in Europe: fast paced, extremely high ownership, and in person in Shoreditch.
• You want a well-defined ticket handed to you each morning.
• You want to specialise narrowly and stay in your lane.

What you get

• Real equity, and compensation that reflects a high bar
• Genuine ownership of product surface area from day one, with the founders in the room
• Relocation support and visa sponsorship, handled properly
• Lunch and dinner covered, 24/7 gym access, and any tool that makes you faster
• A small team with high standards, high trust, and no politics

If this sounds like your kind of problem, apply. A short note on the hardest thing you've built goes further with us than a polished CV.