AI-first Senior Product Engineer

Moonfire; Greater London; Hybrid; GBP 90,000 - 140,000; Full time

Benefits offered by this job

Competitive salary + up to 30% monthly

Equity potential

25 days holiday

Hybrid London-based – 2 days/week

Job summary

Mindstone is seeking a Senior Product Engineer to own problems end-to-end: understand user needs, make product and design calls, build across the stack, ship features, and measure impact. You will work directly with the CTO.

You will ship features, mentor others, contribute to our open-screen ecosystem, and help shape engineering standards as the team grows. Based in or near London, 2 days in the office per week, hybrid.

Qualifications

• Shipped meaningful product that real people use, recently and repeatedly.
• Think and work AI-first: daily use of Cursor, Claude Code, or equivalent
• Full-stack in practice: comfortable from backend systems to frontend product
• Make good product decisions independently, not just technical ones
• Based in or near London, 2 days/week minimum in office

Responsibilities

• Shipping features end-to-end across Rebel, used daily by real teams
• Making autonomous product and technical decisions
• Working directly with LLMs, agents, and MCP integrations
• Contributing to our open-screen ecosystem
• Helping shape engineering standards and culture as the team grows
• Mentoring and setting the bar for quality

Skills

AI-first mindset

End-to-end ownership

Full-stack know-how

Mentoring

Tools

TypeScript

Electron

Job description

About Mindstone

Mindstone is building the reference company for AI transformation. We live in the future we are building - using AI every day to run the company, then helping others adopt it. Profitable, venture-backed, and growing fast.

The Role

An AI-first, product-minded, deeply hands-on Senior Product Engineer. You will own problems end-to-end: understand the user need, make product and design calls, build across the stack, ship, and measure. Working directly with the CTO.

What You Will Be Doing

• Shipping features end-to-end across Rebel, used daily by real teams
• Making autonomous product and technical decisions
• Working directly with LLMs, agents, and MCP integrations
• Contributing to our open-screen ecosystem
• Helping shape engineering standards and culture as the team grows
• Mentoring and setting the bar for quality

About You - Essential

• Shipped meaningful product that real people use, recently and repeatedly
• Think and work AI-first: daily use of Cursor, Claude Code, or equivalent
• Full-stack in practice: comfortable from backend systems to frontend product
• Make good product decisions independently, not just technical ones
• Based in or near London, 2 days/week minimum in office

About You - Bonus

• TypeScript, Electron, or desktop app experience
• Built or integrated AI/LLM features in production
• Previous startup experience (10-50 person team)
• You have hired or mentored, or want to start

What We Offer

• Competitive salary + up to 30% monthly bonus tied to company performance
• Possibility of meaningful equity in a profitable, venture-backed company
• 25 days holiday plus bank holidays plus Christmas week
• Quarterly Swarm Weeks across Europe
• Hybrid London-based - 2 days/week minimum

Diversity and Inclusion

We are committed to building a diverse team and actively encourage applications from candidates of all backgrounds. We particularly welcome applications from underrepresented groups in tech.