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-# uiuc-course-graph
\ No newline at end of file
+# UIUC Course Graph
+
+Static UIUC course prerequisite graph powered by React and Cytoscape.js. Course data is fetched from the UIUC Course Explorer API during build time because the API does not allow cross-origin requests.
+
+## CORS check
+
+```
+$ curl -sD - -o /dev/null https://courses.illinois.edu/cisapp/explorer/schedule/2025/fall.xml
+HTTP/1.1 200 OK
+content-type: application/xml;charset=UTF-8
+server: envoy
+# (no Access-Control-Allow-Origin header)
+```
+
+## Development
+
+```bash
+npm install
+npm run scrape   # generate data/catalog_2025_fall.json
+npm run dev      # start Vite dev server
+```
+
+The GitHub Actions workflow `update-and-deploy.yml` refreshes the catalog daily and deploys the built site to GitHub Pages.