Learn Reference Guide

A growing, multi-disciplinary library of learning notes, explanations, and code examples. Browse the learning library, or search by article title, subject, and category.

bundle install
bundle exec jekyll serve

Open http://localhost:4000/learn/. The site is built by the existing GitHub Actions workflow, which supports the custom catalog generator in _plugins/. GitHub Pages' built-in safe-mode Jekyll build does not run custom generators.

Place an article under its discipline, subject, and optional category:

computer-science/
  algorithms/
    Backtracking/
      N-Queens Problem/
        index.md

Use this front matter:

---
layout: algo
title: My topic
category: My category
attribution_sources:
  - Trekhleb
---

Keep the original source attribution, license notices, and relevant links when adapting material. Existing articles also use Algorithm Visualizer Project and GeeksforGeeks as attribution sources.

The catalog discovers articles with layout: algo and generates missing discipline, subject, and category landing pages at build time. You do not need to maintain link lists or add empty index.md files. Existing articles that also contain subtopics (such as Tree) keep their content and show their child topics in the sidebar.

_data/curriculum.yml supplies optional display names and ordering. Add entries there to customize a new subject; folders not listed are still discovered. Planned subjects without articles are omitted rather than linked to empty pages. The folder hierarchy, not the legacy category field, determines navigation, so similarly named categories in different subjects remain separate.

For a custom collection introduction, add an index.md in its folder with layout: topics-index, a title, and an optional description. Its child-topic cards are populated automatically.

Landing pages use responsive collection cards with article counts. Articles provide breadcrumbs, a sticky contextual sidebar, and child-topic links. The primary theme is the main site's shared terminal.css, bundled at assets/css/terminal.css and loaded after the local layout styles. Learning-page colors use its terminal palette, and collection cards use its interactive card styling. If the shared stylesheet cannot load, the existing local theme in assets/css/learn.css and assets/css/topics-index.css remains the fallback, without requiring JavaScript. Navigation uses local assets; math rendering still uses MathJax. The homepage search runs locally in the browser and matches article titles and their full collection paths. Browsing remains available without JavaScript. Local navigation and assets respect Jekyll's baseurl, including spaces and Unicode in existing article paths.

python -m unittest discover -s tests

These checks build the site with both /learn and an empty base URL, verify catalog links and local assets, and exercise automatic discovery of a new subject.