Nürnberg, Germany
Full-stack engineer building production-grade SaaS.
Focused on fundamentals: robust auth, secure session handling, clean data modeling, and UI flows that stay out of the user’s way. I build SaaS systems with clarity, modularity, and resilience — architecture that scales and security that isn’t an afterthought.
View my workServices
Everything below is work I’ve shipped, not a list of things I’m willing to try. Where there’s a write-up of the decisions behind it, it’s linked.
Full-Stack Product Engineering
Web applications built end to end — React or Next.js on the frontend, Node/Express on the backend, PostgreSQL underneath. Schema to deployed UI, one coherent slice at a time.
Multi-Tenant SaaS Architecture
Designing who exists in a system and what they can reach: separate actor domains, isolation enforced at the query layer, and boundaries that hold when a request comes from the wrong tenant.
See how →Authentication & Session Security
TOTP multi-factor auth, hashed rotating refresh tokens, httpOnly cookies, CSRF protection, and Redis-backed sessions that can be revoked server-side instead of waiting to expire.
See how →Access Control & Audit Design
Permission models, role boundaries, and support tooling like impersonation — built so that acting on someone else's behalf is fully attributable rather than a line in a log file.
See how →API Design & Integration
REST APIs with validated contracts at every boundary, layered behind dependency injection so handlers stay thin, and third-party integrations that don't leak into business logic.
See how →Database Design & Migrations
PostgreSQL schema design, relationships and indexing, versioned migrations that run in CI, and data-driven schemas for the parts of a product that shouldn't need a deploy to change.
See how →Production Hardening
The pass that happens after the tests pass: real response headers, connection pools that actually release, rate limiting, and load testing that finds what unit tests structurally can't.
See how →Testing & CI/CD
Vitest and Supertest suites, integration tests against a fresh migrated database, coverage as a gate, and GitHub Actions pipelines wired to real deployments on Render and Vercel.
Mobile Development
Currently extending into React Native — building the PropertyOS mobile companion for landlords and tenants on iOS and Android.