Migration Without Tears: 2,000 Projects, One New LTS

on YouTube ↗33m

" summary

Open Community Build continuously compiles nearly 2,000 projects from ScalaDex every week (SBT, Mill, Scala CLI) and reports concrete upgrade outcomes: about 20% needed changes to reach latest Scala Next, 400 projects required help for 3.8, and the run uncovers roughly 150 regressions found over four years. Most breakages fix with compiler rewrites and source-version flags; remaining cases need small source edits, updated build tooling, or republishing compiler plugins for exact Scala versions.

AI-written summary · about

" chapters (12)

1. 0:00Scala 3 community build intro
2. 3:40Scala 3.4 deprecations
3. 8:38Infix and match types changes
4. 12:50Migration tools overview
5. 15:01Compiler plugins and givens
6. 17:11Explicit implicits and bounds
7. 21:49Java annotations and tuples
8. 24:39New givens prioritization
9. 27:31Scala 3.8 LTS tooling
10. 29:38Scala 3.9 LTS summary
11. 30:00Migration steps
12. 32:27Results and call to action

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