Incremental compiler taming scalac

on YouTube ↗23m

" summary

Explains how SBT’s Zinc incremental compiler drives scalac via a compiler plugin that records per-source API hashes and dependency names, then reenqueues affected files until stable (typically 1–3 cycles). Describes the current name hashing move from one hash per file to per-name hashes plus name-level dependencies, quantifies rare regressions versus full rebuilds, and lists practical fixes: add explicit return types and avoid multiple unrelated classes per file; code samples and tooling hooks live on the referenced GitHub.

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" chapters (22)

1. 0:00Intro
2. 0:16Incremental compiler
3. 1:12What is Incremental compiler
4. 1:59How many Incremental compilers
5. 2:52SBT
6. 3:58Compiler
7. 5:41Initial change sources
8. 7:06Initial change compilation
9. 7:33SBT compiler plugin
10. 9:06More or less source
11. 10:19traverser
12. 11:38dependencies
13. 13:35name hashing
14. 15:09store dependencies
15. 15:53file dependencies
16. 16:57can we
17. 17:35pull request
18. 18:50precision
19. 20:17speed up
20. 20:29return types
21. 21:30multiple classes
22. 22:14questions

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