Backend Engineer (£60k-£100k + Equity) at Mozart AI

Job Title: Backend Engineer

Salary: £60k-£100k + Equity

Company Description: Mozart AI - VC-backed Generative Audio Workstation

Job Description: Join a talent-dense team of eight building the future of music creation. As a Backend Engineer, you will architect the foundation for millions of users, transitioning from NoSQL to Postgres while scaling media pipelines and payments. This is a high-ownership role for a systems-thinker ready to ship relentlessly in a fast-growing startup.

Location: London, UK

Why this role is remarkable

• Work at the intersection of AI and creativity on a product used by 100k+ creators, including producers for A$AP Rocky and Avicii.
• Backed by $7M+ from top-tier investors including Balderton Capital and the founders of Eventbrite and Frame.io.
• High-impact ownership of critical infrastructure, from database migrations to real-time collaboration primitives in a rapidly scaling environment.

What you will do

• Lead the end-to-end migration from non-relational to relational databases, ensuring zero-data-loss cutovers and canonical schema design.
• Own the payments and entitlements backbone using Stripe and RevenueCat to handle complex subscription lifecycles and cross-platform parity.
• Architect high-concurrency REST APIs and reliable media processing pipelines with global delivery via CDN caching and signed URLs.

The ideal candidate

• Has 3-5 years of experience with Node.js/TypeScript and deep expertise in relational SQL schema design and migrations.
• Demonstrates a production-ownership mindset with strong instincts for CI/CD, observability, and graceful degradation in high-traffic environments.
• Thrives in a high-velocity startup culture, acting as a "specialist generalist" who cares deeply about outcomes after the code is merged.