Senior Product Engineer (Frontend)

CareerOS is a B2B2C career platform serving 100+ top MBA programs worldwide - including Oxford, INSEAD, London Business School, Georgetown, and Notre Dame - along with 30+ employers. We help 500K+ users land jobs they love, and we're growing with real revenue (not just runway).

We're a small, high-output team of 5 engineers based in Barcelona, scaling to 10+. We work in small squads, each owning their area of the product end-to-end. We ship fast, own our decisions, and push each other to do great work.

We're looking for a Senior Product Engineer who writes excellent frontend code, moves fast, and doesn't hide behind "the design isn't clear enough."

You'll work directly with the CTO and CPO, not through layers of management. You'll be in the room when decisions get made and have real input on what we build and how.

Our codebase needs someone who can improve it while shipping. You'll refactor on the go, make smart architectural calls, and produce fast, slick UI - not just "make it work" code. Design input varies - sometimes pixel-perfect Figma, sometimes a Lovable prototype, sometimes a napkin sketch. You adapt and deliver polished results regardless.

Tech stack: React/TypeScript (primary), Node.js backend, some legacy Go. Tailwind, Framer Motion, modern React patterns.

Typical split: ~70% frontend, ~20% backend, ~10% improving what's already there.

• Write excellent code, fast - Clean, performant React/TypeScript. You ship quickly but don't leave a mess behind. Your PRs make the codebase better, not just bigger.

• Refactor on the go - See something ugly? Fix it while you're there. You improve architecture incrementally, not in mythical "refactoring sprints" that never happen.

• Build fast, slick UI - Smooth animations, snappy interactions, no jank. You care about perceived performance as much as actual performance.

• Work with whatever design input you get - Pixel-perfect Figma? Implement it faithfully. Rough prototype? Elevate it. Unclear requirements? Figure it out and move forward. "The design isn't ready" is not in your vocabulary.

• Contribute to backend when needed - You can jump into Node.js, write APIs, debug across the stack. Not your main focus, but you're not afraid of it.

• Build with AI tools - We use Claude Code, Cursor, Lovable and other AI tools daily. You should be comfortable (or excited) to work this way.

• Own your code in production - Continuous deployment means what you merge today is live today. You'll debug, monitor, and improve what you build.

Must-haves:

• 5+ years building production web applications with deep expertise in React and TypeScript

• Writes clean, maintainable code - you refactor as you go, not "later"

• Performance-minded - you know why UI feels slow and how to fix it

• Strong design taste - you can implement pixel-perfect specs AND elevate rough prototypes. Either way, the output is polished

• No "ticket blocker" attitude - unclear design or requirements? You figure it out, propose solutions, and keep moving

• Eye for detail - spacing, alignment, typography, animations. You notice what most engineers miss

• Backend capable - comfortable in Node.js, can write APIs and debug across the stack

• Excellent communication - clear writing, respectful pushback, async-first collaboration

• Fluent English - we're distributed; clear communication is essential

Strong signals:

• You've improved codebases significantly, not just added features

• You obsess over performance - bundle size, render cycles, perceived speed

• Side projects or portfolio that shows both technical depth and visual taste

• Experience with Lovable, v0, or similar AI prototyping tools

• You've contributed to or built design systems

• Experience with animation libraries (Framer Motion, GSAP, Lottie)

• You've used AI coding tools and have opinions about them

Let's be honest about fit:

• ❌ Not "waiting for perfect specs" - If your default response to ambiguity is "I need a clearer ticket," this isn't the place.

• ❌ Not "just ship it, refactor later" - We move fast but we don't accumulate garbage. You improve the codebase as you go.

• ❌ Not a chill 9-to-5 - Startup means more ownership, higher stakes, and hard pushes around launches. We respect personal time and recover after sprints, but when we ship, we ship hard.

• ❌ Not backend-heavy - You'll contribute to Node.js, but 70%+ is frontend. If you want distributed systems, check out our Backend Product Engineer role.

You'll join as one of 5 engineers, growing to 10+. As we scale, there's a clear path to tech lead or staff engineer for the right person. You'll help shape engineering culture and design standards, not just inherit them.

• Competitive salary + stock options - we'll discuss based on experience and location

• Remote-friendly - Barcelona hybrid optional, remote within CET ±2 hours

• Small team, visible impact - 500K+ users, real revenue, your work matters

• Work directly with CTO and CPO - fast decisions, no layers, real influence

• Modern tools - AI-assisted development encouraged, not restricted

Don't check every box but think you'd be great? Apply anyway. We care more about trajectory and taste than credentials.