Product Engineering Intern

CareerOS is a B2B2C career platform serving 100+ top universities worldwide, including Oxford, INSEAD, London Business School, Georgetown, and Notre Dame. We help 500K+ users land jobs they love. We’re a small, high-output team based in Barcelona, operating with American startup intensity. We ship fast, own our decisions, and push each other to do great work.
We work in small squads, each owning their own area of the product end-to-end.
We’re looking for a Product Engineering Intern who’s geeky about coding, loves building prototypes, and wants to ship real AI features that help thousands of students land their dream jobs. This isn’t a typical internship where you work on toy projects. You’ll own meaningful features from start to finish.
What you’ll actually do
You’ll build real features and tools that ship to production.

• Rapid prototype AI features: Use Cursor, Replit, v0, and Claude Code to quickly build and test new product ideas. You’ll go from concept to working prototype in days, not weeks. This isn’t superficial prototyping with drag-and-drop tools. You’ll write real code.

• Build internal tools and dashboards: Support the product, marketing, and GTM teams with custom analytics dashboards, usage reports, and internal tools. You’ll help teams make data-driven decisions by building the tools they need.

• Data engineering and analysis: Write SQL queries to analyze user behavior, build data pipelines, and create activity reports. You’ll work directly with our Postgres database to surface insights that drive product decisions.

• Ship AI/ML features: Own end-to-end development of focused AI features: recommendation improvements, data analysis tools, automation workflows. Your code will run in production and impact real users.

• Work across the stack: You’ll touch frontend (React), backend (Node, Go), database (Postgres), and AI infrastructure. This is a chance to get broad exposure to modern product engineering.

What we’re looking for
Must-haves:

• CS or AI/ML student: Currently pursuing undergrad or master’s degree in Computer Science, AI/ML, or related field.

• Experience with modern AI coding tools: You’ve used at least some of these: Cursor, Replit, v0, Claude Code. You understand how to leverage AI to ship code faster.

• Strong SQL skills: You’re comfortable writing queries, analyzing data, and building dashboards. This is critical for the role.

• Product and user-oriented mindset: You don’t just write code. You think about what users need and build features that solve real problems.

• Passion for building: You’ve built your own tools, apps, side projects, or participated in hackathons. You code because you love it, not just for assignments.

• Self-starter mentality: You can take a loosely defined problem and figure out how to solve it. You don’t need constant direction.

• Fluent English: Written and verbal. Essential for this role.

Strong signals:

• Experience with Node, Go, or React (our tech stack)

• You’ve shipped something to production before (personal project, hackathon, internship)

• Familiar with Postgres or other SQL databases

• Experience with DevOps, CI/CD, or cloud infrastructure (AWS, GCP)

• You contribute to open source projects

• Previous startup or fast-paced engineering environment experience

What this role is NOT
Let’s be clear about expectations:

❌ Not a coffee-run internship: You’ll write real code that ships to production. You’ll own features end-to-end. This is a real engineering role.

❌ Not a structured corporate internship: We won’t give you a perfectly scoped 12-week project. You’ll work on whatever is most important, which changes week to week. You need to be comfortable with ambiguity.

❌ Not a research role: This is product engineering. You’re building features for real users, not writing papers or doing pure research.

What you get

• Competitive internship compensation

• Hybrid in Barcelona or remote

• Work directly with the CPO and senior engineers: real mentorship from people who’ve built products at scale

• Exposure to modern AI-native product development: LLMs in production, AI-powered features, cutting-edge tools

• Real ownership: your code will run in production and impact 500K+ students

• Hands-on experience with DevOps, data engineering, and full-stack product development

• Work on AI features that help thousands of students land jobs: matchmaking, recommendations, career analytics

• Our tech stack: Node, Go, React, Postgres, multi-model AI infrastructure