Fullstack Engineer

About the role

About us

Complir is the AI platform for the product compliance lifecycle, built for retailers, brands, and manufacturers selling physical consumer products across multiple markets.

We believe getting a physical product to market shouldn't mean fighting spreadsheets, PDFs, and supplier emails just to prove it's safe and legal to sell. Product compliance should be continuous, automatic, and understandable, not a bottleneck that slows launches down. We're building the AI infrastructure that makes that possible.

We work with many of the world's largest retailers and brands across fashion, furniture, cosmetics, toys, electronics and many other product categories. We're backed by Y Combinator, and a roster of investors who see what we see: Product compliance is the next major infrastructure category, and we're leading it.

About the role

We're looking for a Senior Fullstack Engineer who wants huge responsibility: Owning the product surface where compliance work actually gets done, for some of Europe's biggest retailers and brands.

The software that you will help us build will make it much easier to sell safe products. Dense regulatory data, AI-generated risk assessments, and document workflows all have to land in an interface a non-technical expert can move through quickly and confidently. You'll design the data models and APIs that make it possible, then build the surface itself: presenting model output with the right confidence and citation so a compliance manager can act on it, making a corpus of 100+ regulatory frameworks feel navigable, and keeping a screen full of async AI work feeling instant and actionable. By making this data easier to act on we will in turn make the products sold on all the world's markets much safer for consumers.

Our stack is Next.js and TypeScript for the app, React + Vite for our Adobe plugins, NestJS and Inngest on the backend, PostgreSQL, hosted on Vercel and Azure. If you haven't touched all of it, that's fine. What matters is that you want to build things that people can rely on and enjoy using.

Where you'll be based

You'll be in-office at our central Copenhagen HQ, working alongside the whole team. We're a small team that moves fast, laughs a lot, and celebrates wins loudly - and the distance between "a user hit a problem" and "the fix is in production" is measured in hours, not sprints.

What you'll do

- Build new user-facing features end to end: data model, API, and the UI components users actually touch

- Own the frontend craft: component architecture, state, performance, and the details that make an interface feel finished rather than merely functional

- Ship features that are deeply integrated with LLMs

- Turn a compliance expert's judgment into systems: Encode how classification, risk, and requirements actually work into pipelines that scale, then make the output legible to a non-expert

- Work directly with customers and founders to decide what to build next, then build it

- Shape the architecture, tooling, and engineering culture as the team grows

You will love this job, if you are:

- A senior engineer with several years shipping production fullstack applications, fluent in TypeScript and at home in React and Next.js

- Someone with real frontend judgment: You have opinions about component APIs, interaction detail, and how a UI looks and feels

- Product-minded: You care what the user is trying to do, not just what the ticket says, and you push back when the product shape doesn't feel right

- Experienced with (or seriously hungry to go deep on) LLM-powered systems: RAG, embeddings, orchestrating multiple models in one workflow

- Someone who treats model output as an engineering problem: Evals, grounding, and failure modes, not vibes

- Comfortable with ambiguity and speed: Small team, fast decisions, no spec handed down from above

- Excited to work on-site in Copenhagen with the whole team

- A builder at heart

If you'd rather own the inference pipeline than the interface, take a look at our Backend Engineer and Data Engineer roles instead. Same team, same problems, different end of the stack.

What you get

- Ownership of the interface Europe's biggest retailers and brands do their compliance work in, on top of AI with actual stakes: our system answers "can I legally sell this product?"

- Real ownership of the code, the architecture, and a real say in what gets built

- Zero layers: You sit next to the founders, the AI team, and the compliance experts whose knowledge you're turning into software

- Ground floor of a category-defining company, backed by Y Combinator and investors betting on product compliance becoming the next big thing

- Competitive salary and equity

- An office where the pastries are mandatory

If you've read this far and thought "I want to own that interface," we'd like to meet you.