Free public beta until December 4, 2026: every course is open, no card needed. After that, the first chapter of each course stays free and full access is a one-time $39 ($19 for up to 100 founding members chosen for helpful feedback). Your progress is kept. How the beta works

exception cause

The exception that led to this one, kept inside it when one exception is wrapped in another.

Passed to a constructor such as Exception(String, Throwable) and returned by getCause(); stack traces print it under Caused by.