Code City

Why it's ranked here

The hook is real and cheap to try: zero install, MIT licensed, no build step, and a shareable link per repository. The substance is thinner than the pitch. Line counts are guessed from byte size, per-file churn and age are random numbers, every file's bug count is fixed at zero, and the dependency list handed to the renderer is always empty. What you get is an accurate picture of folder structure and relative file size, dressed as something more analytical.

What's good

The layout code is honest work: a recursive treemap sized by estimated lines, so big directories visibly dominate and deep nesting reads as nested blocks. Vendored and generated folders such as dependency caches, build output and coverage are skipped, along with lockfiles and dotfiles, so the skyline reflects authored code. Background filler towers are merged into one mesh and capped at fifteen hundred, which keeps the frame rate sane. Error messages distinguish a missing repository from an exhausted rate limit.

Tradeoffs

Several advertised signals are not wired to data. Churn and file age are generated with a random number call, the commit scan for fix and bug keywords collects messages rather than files and is never used, and dependencies are returned empty. Unauthenticated GitHub access allows sixty requests an hour and each city costs five, so heavy use needs a personal token pasted into browser storage through the console. There are no tests; the test script only prints a notice. Private repositories are not supported.

How to use it well

Use it for a first-look tour of an unfamiliar public repository, or as a visual for a talk or README, where the shape of the folders and the relative weight of files is the point. Do not read fires, glow or roads as findings about quality or coupling. For heavy exploration add a token to lift the rate limit. If you want to extend it, the code is plain browser modules with no build, so edits show on refresh. For real churn or dependency analysis, reach for a dedicated tool.

Observed

License

MIT (LICENSE)

Language

Plain JavaScript ES modules plus one HTML entry page

Install surface

None; static files served with npx serve, Three.js loaded from a CDN import map (app/index.html)

Interface

Browser web app; repository selectable via a repo query parameter (app/index.html)

Data source

GitHub REST API called directly from the browser, public repositories only (app/github-api.js)

Line counts

Estimated from file byte size divided by 40, not counted (app/github-api.js)

Churn and file age

Randomly generated per file, not derived from history (app/github-api.js)

Dependency data

Always returned as an empty list (app/github-api.js)

Tests

None; test script prints a placeholder message and exits (package.json)

Authentication

Optional personal token read from browser localStorage (app/github-api.js)