Nathan de Bock

loyalty saas for local merchants · Supabase (Postgres, RLS), Stripe, Playwright, feature flags

• Took over a live loyalty platform originally generated with Lovable (Supabase/Postgres, 103 tables, ~280 migrations) and re-engineered its backend with zero downtime. Opened with a risk audit: 19 ranked risks, turned into 27 work packages approved by the client.
• Row-level security and explicit grants on every table and function, with cross-tenant integrity constraints. The access matrix is generated from the catalog and enforced by 1,439 automated HTTP checks across roles.
• Made every value-moving write (points, coupons, SMS credits) transactional and idempotent; Stripe webhooks are processed once and in order, and return 5xx on failure so Stripe retries. Rolled out behind 14 feature flags, with additive migrations, rollback plans and restore drills.

serlei.ch · Next.js, Supabase (Postgres, RLS), Stripe, Docker, nginx

• Production e-commerce for an independent Swiss upcycling fashion brand — CHF-native Stripe checkout, custom in-place CMS for a non-technical operator, self-hosted on a Scaleway VPS.
• Sole engineer. 140 commits over 7 months, live since Oct 2025.
• Diagnosed and fixed a 3-cause production incident that silently dropped every Stripe webhook (misrouted URL, swallowed errors, an RLS gap that recurred in 4 files) — single commit, root cause documented at nathandebock.com/projects/serlei.

App Store + Google Play · React Native (Expo), Redux Toolkit, Supabase, EAS Build

• B2B loyalty mobile app for French works-council (CSE) employees — iOS + Android, 4 user roles, two parallel auth strategies, a Next.js web companion for deep links.
• Sole engineer. 89 commits over 5 months, shipped to both app stores.
• Diagnosed a 4-cause Android-only rendering bug across native map marker bitmaps, billing config, and a race condition — 5 days, isolated and fixed each layer independently.

app.backstagerate.com · React, Node/Express, Python/FastAPI, MongoDB, Docker, Claude API

• B2B employee-engagement survey SaaS — held 537 employees, 22 surveys and 72,786 responses inside MongoDB Atlas’s 512MB free tier by materializing every dashboard aggregate at write time.
• Built the GDPR-aware analysis pipeline behind it and instrumented its unit cost: €0.234 per full run, measured across 212 real API calls, not estimated.
• Ran a pre-release audit that caught a plan-gating bug (JWT missing a required field, silently downgrading paid accounts) before any customer hit it.

cse-martinez.fr · Next.js, MongoDB, NextAuth, Docker

• Internal employee portal for the works council of a Cannes palace hotel — name-only auth for staff with no corporate email, mixed public/private document storage.
• Sole engineer. 97 commits over 12 months (2 dormant stretches; ~6–7 months of active development).
• Root-caused and fixed a production image-serving bug (presigned URLs expiring under Next.js Image Optimization re-fetch) after an initial fix addressed only the symptom.