# Full‑Stack Development > Selected Engineer ApS work demonstrating Full‑Stack Development — the achievements that prove it. - [Led the development, deployment, and support of over 30 GIS projects, demonstrating expertise in PostgreSQL, Bash, Python, JavaScript, GDAL, ArcGIS, PostGIS, and Mapbox technologies.](https://data.engineer.company/portfolio/led-the-development-deployment-and-support-of-over-35/) - [Architected, developed, implemented, supported infrastructure, data processing, and the map application for 2 years non‑stop without any weekends, holidays, or vacations, 10–14 hours a day.](https://data.engineer.company/portfolio/architected-developed-implemented-supported-infrastructure-data-processing-and-55/) - [Architected a layered maritime platform separating a Next.js PWA frontend, a Go (Huma/Fiber) API, and a PostgreSQL function layer, keeping all business logic in the database.](https://data.engineer.company/portfolio/architected-a-layered-maritime-platform-separating-a-next-57/) - [Built the hiring marketplace and the seafarer career workspace — 151 stored functions across 48 tables — covering vacancies, applications, certificates, rank progression and verified sea time.](https://data.engineer.company/portfolio/built-the-hiring-marketplace-and-career-workspace-107/) - [Built a database‑driven CV, references, portfolio and cover‑letter generator in Python — 41 modules, 10,580 lines — rendering six output formats from one 23‑table SQLite source assembled by a 19‑step idempotent pipeline.](https://data.engineer.company/portfolio/built-a-database-driven-cv-and-portfolio-generator-144/)