End-to-End Product Engineer (AI-Driven)

Mainloop AI; Barcelona; On-site; EUR 70,000 - 100,000; Full time

Job summary

Mainloop AI in Barcelona is seeking a Full-Stack Product Engineer who owns a product end to end—from users and roadmap to build and release—without gatekeepers between you and the people who use it. You’ll talk to users in person when possible, decide what comes next, and build front to back.

You’ll ship features, measure impact, and iterate based on real usage in a fast AI-native environment. English is the working language; Spanish helpful; Catalan not required.

Qualifications

• What you have shipped a product used by real users.
• Experience owning end-to-end product life cycle.
• Strong written and verbal English; Spanish helpful.

Responsibilities

• You own a product end to end, from idea to release.
• You talk to users in person when possible and gather feedback.
• You decide what comes next and what to postpone with justification.
• You build front to back and ensure the feature works in production.
• You measure impact and report on usage, time saved, and error reduction.

Skills

Product ownership

Frontend & Backend

User research

Tools

Claude Max

AI agents

Job description

Mainloop AI in Barcelona is seeking a Full-Stack Product Engineer who owns a product end to end—from users and roadmap to build and release—without gatekeepers between you and the people who use it. You’ll talk to users in person when possible, decide what comes next, and build front to back.

You’ll ship features, measure impact, and iterate based on real usage in a fast AI-native environment. English is the working language; Spanish helpful; Catalan not required.