Zeitwerk Internals

on YouTube ↗34m

" summary

Zeitwerk is the Ruby autoloader that scans configured root directories just one level deep, sets autoloads for files and directories, and defers loading until Ruby triggers those autoloads; it intercepts require to do bookkeeping, defines missing modules on the fly and then descends into that branch, and implements reloading by removing constants and entries from loaded_features. Implementation details: ~1k LOC, per-loader deterministic inflector, tracepoint on class event, and uses absolute paths for require for speed.

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" chapters (6)

1. 0:00Introduction to Zeitwerk
2. 2:35Ruby constants and namespaces
3. 12:57How Zeitwerk sets autoloads
4. 21:15Triggering autoloads in Ruby
5. 29:28Reloading and eager loading
6. 33:47Summary and Q&A

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