OfrecemosFounding Software Engineer2 positions · Valencia, on-site · Full-timeruit (re use it) gives professional second-hand sellers the software to centralize, manage and optimize their operations, selling on every marketplace from one place. We've just raised ~€1 M in venture capital. Our goal is to grow 100x in 18 months.We're looking for two software engineers with deep knowledge of, and a passion for, software engineering. Among the many challenges ahead of us: Integrate 100-200 marketplaces in a year, through documented APIs or reverse engineering.Build an engine that analyzes and compares historical and real-time prices across the entire second-hand market, with new goods as a reference.Build the infrastructure to support ~5-10 K businesses and hundreds of thousands of active users across several countries and continents.Ship a real-time service that creates and edits high-quality images.Design a product so good that people want to use it, and pay for it. (We'll probably rebuild our website, mobile apps and web app more times than we'd like.) What we don't care about: Which programming language(s) you know.Years of experience. We value them, but what really matters to us is your drive to solve problems and your ability to solve them. What we do care about: That you use AI every day. Really use it. For reference, we have ~20 Claude accounts, and last month two of us shipped ~1,000 PRs. We love what we do.Solid engineering fundamentals, and the ability to design, build and maintain complete systems, end to end.That you're happy to talk to customers over chat. We all do customer support and demos. Whoever closes the most tickets gets €3,000 at the end of the year. So far,



our chatbot is winning...A permit to work in Spain and willingness to relocate to Valencia (as a rule, we don't sponsor visas).English. Part of our team will probably be international. Nice to have: Familiarity with our stack: Dart/Flutter/WASM on the front end, and Redis, Celery, Postgre SQL and Python/Django (heavily tuned ASGI) on the back end. We don't expect you to have written a line of code with them, but you should know the tools we use.Experience with scraping, crawling, reverse engineering, anti-bot systems and the like.Experience with well-designed systems that have scaled. You’ll work at Spain's best startup accelerator, next to the beach in Valencia, at a startup that will have a general impact, alongside an extraordinary team. The job is on-site, Monday to Friday, at Lanzadera.You choose: a very competitive, above-market salary, or a market salary plus a very competitive phantom share plan. On top of that, ~€2,000 a month for AI and, honestly, anything else you think you need to help make second-hand the first way people shop.How we hire: A 5-minute call to understand your situation.A 45-minute video call to get to know you properly. No coding, nothing technical, nothing to prepare.A conversational technical interview: 60 minutes where you show us your setup and how you work,



with a mini task, and we talk about programming fundamentals (see the concepts at the end).A system design session, as a team with us. You pick one of the challenges above and we solve it together. Step 4 is on-site in Valencia. If you can, we recommend doing steps 3 and 4 on the same day in person, and having lunch with the team. It's on us.Ironically, we use AI for everything, and yet I've spent an hour writing this post by hand, because I believe it's the only chance I have to convince you that joining ruit could be the best decision you make: fun, challenging, and good for people. I only get this one chance. Your email is exactly the same. Any candidate who applies through the Linked In button or uses AI to write this email will be discarded.What we’ll talk about: Concurrency and async.JSON validation, ORMs and SQL.Background task queues and their brokers (e.g. Celery and Redis).HTTP clients and TLS.Error handling and the philosophy behind each language's approach (e.g. Python vs Go vs Rust).Databases and caching.Low-level networking and protocols (HTTP, Web Sockets…) and their quirks.API integrations and reverse engineering.Dev Ops: Linux, Docker and Docker Compose, deployment strategies and zero-downtime deployments.Observability: metrics, logs and traces.Scaling. If you work with Python, we'll also talk about the GIL, async in Django, generators, and how to make Python reliable with type hints and static analysis.And of course, how you work with AI: how you use agents, skills and plugins, how you run several sessions in parallel, and so on.#J-18808-Ljbffr

📌 Founding Software Engineer (Valencia)
🏢 Ruit
📍 Valencia