Product Engineer at Publicit Global in Barcelona, Catalonia, ES

About Publicit

Be everywhere. Publicit is the European self-service platform for omnichannel advertising: one dashboard that puts a campaign on connected TV, billboards, digital screens in the street, metro stations, mobile apps and press. Things that used to take three agencies and six weeks now take a few minutes and a work email.

Underneath that simple dashboard sits the hard part, our own hybrid ad exchange. Every time an ad slot opens anywhere in our network, a TV in a living room or a screen in a metro corridor, an auction has to run and finish before anyone notices it happened. Milliseconds. Not "fast for a web app" milliseconds; the kind where garbage collection pauses are a bug, and where a query to a database you didn't need to make is the difference between winning and losing.

Most of the industry solved this by stacking more cloud servers on the problem and accepting the latency. We took the opposite bet: rebuild the decision path from the ground up, in Rust, with hardware acceleration and GPU-based decisioning, so we can afford to actually think about each auction. Is this ad relevant to this viewer? Is this placement safe for this brand? What is it genuinely worth? All of it in the time most exchanges spend on network overhead alone.

We're a small engineering team in Barcelona building real infrastructure in a market where most players stopped building years ago. Nobody here is maintaining someone else's platform.

The role

This role sits across both halves of the company: the exchange that runs the auctions, and the platform our customers actually touch. Very few engineers work across that line. The ones who do end up making the decisions that matter, because nearly every hard question here turns out to be a question about the seam between them.

An advertiser sets a budget in a form. Somewhere downstream that becomes pacing logic in a system with a millisecond budget, and when the two disagree, somebody has to hold the whole picture in their head to see why. That person is you.

Half your week is building. The other half is making sure the right things get built, in the right order, by the right people.

We know where we're going and we have the roadmap to get there. What we're looking for is someone to take a piece of it and own it end to end: how it's shaped, how it's built, who builds it with you, and the number that says whether it worked.

This role grows with the company. You'll set how we build here, and over time, who builds it.

What you'll do

• Own the connection between the exchange and the platform. Campaigns, budgets, targeting and reporting all have to mean the same thing on both sides of that line. Keeping them honest is one of the highest-leverage jobs in the company.
• Lead delivery on what you own. Break the work down, sequence it, keep it moving, and unblock the people around you. Not by running a process, but by being the person who sees the whole thing.
• Build. TypeScript and React across the product surface, plus the backend work a feature needs to actually exist. You ship what you argue for, and the people you work with will read your code.
• Set the technical direction for the product side. How it's structured, what the standards are, what we stop doing. The bar you hold yourself to becomes the bar.
• Own scope. Decide what ships now, what ships later, and what doesn't ship at all. Then defend it.
• Talk to advertisers constantly. Onboarding calls, support conversations, watching over someone's shoulder while they try to launch. The best decisions here come from noticing where somebody hesitated.
• Own the numbers. How many people who sign up launch a campaign. How many come back and launch a second. Where they drop, and why. Instrument it, then move it.
• Raise the people around you. Review code like it matters, explain the reasoning, and make the person better rather than just the pull request.

What we're looking for

• Around 4 to 6 years building software that real people used. Not years in a seat. Things that shipped and that you can talk about honestly.
• You've owned a product or an area end to end. You decided what got built, you shipped it, and you lived with the consequences when you were wrong. That matters much more to us than how many people reported to you.
• Strong TypeScript and React. You build what you argue for, so the building has to be real.
• You're comfortable being the least expert person in the room, then not being. You won't know the exchange side on day one. Nobody does. We care that you can get deep enough, fast enough, to make good calls across it.
• You have product opinions and you change them with evidence. Both halves. Opinions without evidence is ego; evidence without opinions is a committee.
• You'll talk to customers without being asked. Not "willing to". Actively wants to. If your instinct when a feature underperforms is to go ask three users why, we should talk.
• Taste. You notice when something is clunky and it bothers you. It's a real skill and it can't be taught in the time we have.
• You want to be in the room. This role is on-site in Barcelona. Working across two systems and a team happens fastest at a whiteboard.

Bonus points

• You've started something of your own, a company, a product, a freelance practice, and know what it feels like when nobody is coming to save you.
• You've worked, studied or lived abroad, or in a team spread across countries. Our customers, our inventory and our roadmap are European and you'll feel it from week one.
• You've worked near low-latency or high-throughput systems, even if you didn't build them. You'll be reasoning about one constantly.
• You can hold your own in a design conversation, or you're the engineer designers actually like working with.
• You're comfortable with PostHog and analytics. You'll be answering your own questions about user behaviour, constantly.
• You've built self-service or product-led growth flows, where the product has to sell itself because there's nobody on the phone.
• You know the advertising world from either side, agency, brand or platform. Genuinely optional; we'll teach you.

How we hire

1. Application. CV plus a link to something you built and shipped. Two or three lines on what it does, who used it, and one decision you made that you'd still defend today.
2. Intro call (30 min). Us, you, mutual honesty about what this job actually is.
3. Technical and product conversation (60 min). We go deep on something you've owned, then look at a real problem that crosses both sides of our system.
4. Practical exercise. A small, paid, time-boxed piece of real work: a slice of our product, your call on what it should do, and you build part of it.
5. Team and founders. You meet the engineers you'd be working with, then us.

We aim to close the whole process within two weeks.

Why join

• Scope that doesn't exist at a larger company. Two systems, one head, no committee in between. At any company past fifty people this job is three jobs and you'd get one of them.
• Real infrastructure on one side, real customers on the other. Most engineers get one or the other for their whole career.
• A problem nobody in Europe has solved. Making advertising across TV, street, transit and mobile as easy as boosting a post is not a solved problem. If it were, we wouldn't exist.
• Engineers worth arguing with. You'll be surrounded by people who care as much as you do. That's rare and it makes the work better.
• Competitive salary and meaningful equity. You share in what you help build.
• Barcelona. A team that works hard in the same room, and then goes and has lunch like human beings.

How we work

Extreme ownership. If something is broken, it's yours, regardless of whose job it was. We don't wait for someone else to pick up a dropped ball. We pick it up, then fix the process that dropped it.

Craftsmanship. "It works" isn't the bar. Details compound: a clean interface, a well-named metric, a doc someone can actually follow. We build things we'd be happy to have read back to us in a year.

Speed with direction. Time is the only resource we can't buy more of. We move fast, but we choose ruthlessly what to move fast on. Speed without focus is just noise.

Talent density. Every hire should raise the average. We reward contribution over tenure and give ownership to whoever earns it. Strong people want to work with strong people; that's the whole flywheel.

First principles. Advertising technology is full of things that are true only because they've always been done that way. We strip problems back to what's actually required and rebuild from there. It's the only reason a team our size can outbuild incumbents.

Be a good human. Direct, honest, kind. We give hard feedback with respect and celebrate wins without ego. We're doing something difficult, and it's better in good company.

Apply

Send your CV and a link to something you've built to careers@publicit.es or apply through the link on this posting.

Data protection

The personal data provided in your application and during the selection process will be processed by Publicit Global SL, acting as Data Controller.

By sending us your CV, you consent to the processing of your personal data for the purpose of evaluating and selecting you as a candidate for this position. Your personal data will be treated confidentially and will only be used for the recruitment process of the selected job offer.

Your personal data will be deleted after three months of inactivity, in compliance with the GDPR and applicable data protection legislation.

To exercise your rights of access, rectification, deletion, portability or objection in relation to your personal data, subject to the GDPR.

For more information, visit https://publicit.com/privacy-policy.

By submitting your application, you confirm that you have read and understood this clause and that you agree to the processing of your personal data as described.