Full-Stack Builder - First Engineer : Knowledge Graph & Consumer App

Full-Stack Builder, First Engineer. Contract remote, You work with our CTO, who owns the architecture and reviews all work. You build, and you push back when something is wrong. A personalisation platform with four connected parts. You build all of them: ∙ Knowledge base: products, ingredients, and how they relate. Graph-shaped data in Postgres. The core asset, so the model has to be right. ∙ Digital twin: user profiles with attributes that expire, version, and delete fully on request. ∙ Consumer app, mobile-first. Progressive onboarding, product lookup, short answer with expandable detail. ∙ Multi-tenant brand platform: customers upload catalogues. Messy Excel in ten languages in, clean data out. Customer A never sees Customer B. A deterministic scoring engine exists in Python. It stays deterministic and traceable. You make it a service, not a model. Stack: PostgreSQL, Python, React, EU cloud. Need: real schema design, Postgres in depth, solid backend, enough frontend for a consumer app and a data-heavy admin flow, plus deployment. Not needed: ML, Kubernetes, microservices. Solid, not fashionable. Engagement: 20h/week. POC in 8-10 weeks, full build into 2027. To apply, send: 1. A schema you designed, and one thing you’d change about it now 2. How you keep one customer’s data invisible to another, and the tradeoffs 3. Two projects you built end to end Shortlisted candidates are paid for a small task before we commit.