A full-stack livestock farm-management SaaS maintained over two years: Express/MongoDB API with 13 per-species models, subscription billing, sandbox API keys and audit logging; a Redux-powered React dashboard; and design-first wireframes - run with a small team and CI.
A NestJS/MongoDB financial-system backend - users, accounts, transactions, role-based access - with unit and e2e tests, Sentry/Loggly observability, and a TypeDoc API reference deployed as its own documentation site.
A two-generation fleet-management API (2020–2021): GPS trip tracking and vehicle records in v1, re-platformed in v2 as a multi-tenant SaaS with companies, plans, API keys, sandbox mode, and guarantors - built by a two-person team, and the origin of a backend boilerplate reused for years.