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# Full-Stack Engineer - Mainloop

- **Company:** Ai-powered
- **Location:** Barcelona, Spain
- **Contract:** Permanent contract
- **Skills:** Artificial Intelligence, Web Applications
- **Published:** September 26, 2026
- **Apply:** https://www.recruit.net/job/full-stack-engineer-mainloop-jobs/6EB72DE174B61874

## About the Role

faster than a normal job would let you. A degree, a bootcamp, a self-taught route and a stack of side projects are all fine. Years of production ownership are not expected - that is what the senior seat and the certificate are for.We do not care what you studied. We care what you have built and whether you can talk us through the decisions in it.How we hireOur process is unusual, so here it is up front. Four rounds, and none of them is a puzzle.Fifteen minutes with Edouard. A short first conversation - who you are, what you are after, and what this actually is. Enough for both of us to work out whether the next one is worth an hour.A thirty-minute conversation. What you have built, how you work, and how you think about it. We will ask you to walk us through something you built and then to justify a specific decision inside it. There is no way to prepare for that and it is not meant to catch you out; it is how we tell understanding from

## Description

running thing. An agent will write most of them; making sure the coverage is actually there is your job, and you can look at a suite you inherited and say why it is a bad one.You use coding agents in your work and you read their output like you would a colleague's.You can pick up a codebase you did not write and explain what it is doing before you change it.English, fluently. It is our working language - we work across roughly fifteen countries. Spanish is genuinely useful day to day. Catalan is not required.Barcelona. This is a team that sits together, especially in its first year.For the four junior seats specifically, read the list above as the direction of travel rather than the entry price. What we actually need on day one is narrower and we will say it plainly: you can build a working web application front to back, you have used a coding agent seriously enough to have opinions about where it goes wrong, and you want to get good at this