Contribute

CoreCraft is a growing, open collection of core Java building blocks explained from scratch. New concepts and interactive visualizations are welcome — drop a file, open a PR, and it appears on this site automatically. No manual index editing.

How auto-discovery works

A CI step (docs/gen-manifest.mjs) scans docs/concepts/ and docs/visualizations/, extracts each item's title and one-line description, and regenerates docs/content.json. The landing page renders its cards from that manifest — so adding a file is enough.

Add a concept

Create docs/concepts/<your-slug>.md, starting with a title and a one-line blockquote summary:

# Your concept title

> One sentence shown as the card description and why it matters.

...the rest of the explanation...

The # heading becomes the card title, the > line becomes the card description. Open a PR — it appears under Concept deep-dives.

Add a visualization

Create docs/visualizations/<your-name>.html from the skeleton in the repo's CONTRIBUTING.md. Use the shared var(--color-*) variables so it works in light and dark mode. The <h1> becomes the card title, the <p class="lead"> the description. Open a PR — it appears under Interactive visualizations.

Contribute a kata (code)

• Keep it from scratch and educational (no third-party libraries for the core).
• Add a focused JUnit suite — mvn test must stay green.
• Add a matching concept doc and, ideally, a visualization.

Local preview

node docs/gen-manifest.mjs          # refresh content.json from your files
python3 -m http.server -d docs 8000  # open http://localhost:8000

Full guide: CONTRIBUTING.md · Source: GitHub