Columbia Open Data Service
The central university service publishing data feeds to software developers in programming-friendly formats such as JSON and XML — the course directory, the CLIO library catalogue and building access among them — with documented refresh schedules, data diagrams and element documentation. It is the closest thing Columbia has to a developer portal, and access is affiliation-gated: any member of the University community may log in with their UNI to consume the feeds, and there is no external, partner or application tier for anyone else. On this run the service and its documentation were unreadable — the host sits behind a Cloudflare managed challenge that returns HTTP 403 to every non-browser client, including one presenting full browser headers. The access model described here is carried forward from the June 2026 profile and is not re-verified.