Move fast and fix things
summary
Scalafix is a rewrite-and-lint tool that actually performs code transforms: it uses Scalameta’s semantic DB and token-level patches to change symbols, add imports and preserve formatting rather than reprinting ASTs. The repo ships SBT/CLI scaffolds, rule templates and worked examples (notably Cats migrations and Scala2→Dotty rewrites), the replace-symbol and replace-tree APIs run and apply patches, and most examples compile; current gaps include macro-aware semantics and automated backtracking after compile failures.
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chapters (20)
- 0:00Introduction
- 0:54Agenda
- 1:20What is ScalaFix
- 6:40The perspective
- 9:24Is this sustainable
- 12:28Syntax Trees
- 18:48Scala Meta
- 24:11Colour Fix
- 24:43Effects
- 25:07Context
- 25:32Semantic DB
- 26:02Live examples
- 26:24How to start
- 28:48Structure
- 31:32Debugging
- 32:40Testing
- 34:19SD Explorer
- 40:28Scala Fix API
- 42:53Whats next
- 44:56Questions
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