CareerOS

Junior 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. 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 Junior Engineer who's strong on frontend and eager to grow into a full-stack developer. You'll ship real features from day one, learn fast, and work alongside senior engineers who'll help you level up.

What you'll actually do

You won't do busywork. You'll ship real features to real users.

• Build frontend features - React and TypeScript will be your main focus. You'll implement UIs, work with design, and ship features users interact with daily.
• Grow into full-stack - We expect willingness to work across the stack. You'll start touching Node.js APIs and databases as you get comfortable.
• Build with AI tools - We use AI coding tools daily (Claude Code, Cursor - team members pick what works for them). You should be comfortable (or excited) to work this way.
• Work directly with design - Implement responsive interfaces from Figma. Ask questions when specs are unclear.
• Learn in production - We do continuous deployment. You'll see your code live quickly, learn from mistakes fast, and improve with each feature.

What we're looking for

Must-haves:

• 1-2 years of experience (or strong projects/bootcamp background) building web applications
• Confident with React and TypeScript - You can build UIs, manage state, and work with components
• Code quality - Knowledge of SOLID principles and clean code practices
• User focus - You have a strong sensibility for UI and UX and understand what makes a web application feel responsive and polished
• Willing to learn full-stack - You're curious about how the backend works and want to grow in that direction
• Good communication - You ask questions when stuck, share progress, and work well with others
• Comfortable with feedback - You take code review seriously and want to improve
• Fluent English - We're a distributed team; clear written communication is essential

Strong signals:

• Some backend experience with Node.js (even from side projects)
• You are familiar with React Native
• You have side projects or contributions that show you build things because you're curious
• You've used AI coding tools and are excited about them
• Bootcamp grad or self-taught with a strong portfolio
• You've worked in a fast-paced environment before

What this role is NOT

Let's be honest about fit:

• ❌ Not a laid-back internship - This is a real engineering job. You'll ship to production, own features, and be expected to deliver.
• ❌ Not highly structured - You'll get support and mentorship, but you need to be proactive about learning and asking for help.
• ❌ Not frontend-only - Frontend is your primary focus, but if you only want to implement user interfaces, this isn't the right fit.

What you get

• Competitive junior salary + stock options
• Fully remote - Work from anywhere (EU timezone preferred for overlap)
• Mentorship from senior engineers who want to help you grow
• Small team where your work visibly matters - we have 500K+ users and real revenue
• Direct access to founders and fast decision-making
• Clear growth path - we promote from within as we scale

How to apply

Send us:

1. Your CV/LinkedIn
2. A link to something you've built (side project, portfolio piece, or contribution) - tell us what you learned building it

No cover letter needed. We review every application.

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