# Frontend Engineering > Selected Engineer ApS work demonstrating Frontend Engineering — the achievements that prove it. - [Directed full‑stack GIS map development, overseeing PostgreSQL, Mapbox, ReactJS, and NodeJS to deliver an integrated solution.](https://advisory.engineer.company/portfolio/directed-full-stack-gis-map-development-overseeing-postgresql-25/) - [Presented 200 UI/UX improvements for the GIS map application, boosting revenue by 10x through enhanced software features.](https://advisory.engineer.company/portfolio/presented-200-ui-ux-improvements-for-the-gis-28/) - [Designed the product's UI and UX end to end — directory grids, dual card/table views, live requirement validators and breadcrumb navigation.](https://advisory.engineer.company/portfolio/designed-the-product-s-ui-and-ux-end-76/) - [Set the platform's founding decisions in the weeks after the repository opened in November 2025 — the layering, database‑first data access and the zero‑warnings bar — and they still hold nine months on.](https://advisory.engineer.company/portfolio/set-the-platform-s-founding-decisions-in-november-2025-80/) - [Built a layered automated test suite — 981 Go tests, 543 frontend and browser specs, 494 SQL behavioural tests — with mutation testing, property‑based tests and an accessibility gate.](https://advisory.engineer.company/portfolio/built-a-layered-automated-test-suite-across-four-layers-94/) - [Built the operator back‑office — around 40 admin routes and 128 components covering claims, moderation, feature flags, cache and diagnostics — so the platform can be run without database access.](https://advisory.engineer.company/portfolio/built-the-operator-back-office-for-the-platform-102/) - [Built company ownership claims end to end — a user claims a company, an administrator adjudicates, and an approval rewrites the authorization graph that decides who is allowed to edit what.](https://advisory.engineer.company/portfolio/built-company-ownership-claims-end-to-end-103/) - [Built the platform's social layer — posts, feed, groups, mentions, a follower graph and an occasions digest — on the same function‑first data layer as the rest of the product.](https://advisory.engineer.company/portfolio/built-the-platform-s-social-layer-106/) - [Built a commit gate of 22 one‑line linters plus five that earn a paragraph, with no warning tier and no inline suppressions permitted, covering HTML, CSS, JavaScript, Python, YAML, Markdown, shell, links, spelling, secrets and typography.](https://advisory.engineer.company/portfolio/built-a-22-linter-commit-gate-127/) - [Cut the site's browser‑driven quality gate from 1,636 seconds to 615 by scheduling its checks longest‑first through a worker pool bounded to four lanes, after measuring that alphabetical order cost 320 seconds against 224.](https://advisory.engineer.company/portfolio/cut-the-visual-quality-gate-to-ten-minutes-128/) - [Brought 10,242 lines of quality‑gate JavaScript under a formatter and a linter after establishing it was the largest body of code in the repository and the only one nothing read, fixing 13 findings and suppressing none.](https://advisory.engineer.company/portfolio/brought-the-quality-gate-code-under-a-linter-143/) - [Adopted Swift 6 complete strict concurrency with no actors, bridging a blocking C event loop to the main actor through one producer, one consumer and one ordering — after establishing that a task per event loses the ordering the interface depends on.](https://advisory.engineer.company/portfolio/adopted-swift-6-strict-concurrency-over-a-c-event-loop-156/) - [Rewrote the application's error messages against a written tone standard after a refused sign‑in blamed the user for mistyping when the provider actually required an app‑specific password, and covered it with a test that names the provider.](https://advisory.engineer.company/portfolio/rewrote-the-error-messages-against-a-tone-standard-162/)