Typelevel's Road to Scala 3
summary
Typelevel documents the concrete work to reach Scala 3: over 60 projects including cats, cats-effect, fs2 cross-build to milestones; simulacrum via scalafix replaces many Scala 2 macros; Scala 3 implements built-in type lambdas and solves SI-2712 pain (fix landed in 2.12), so common hacks disappear. Remaining gaps: macro-based tools require full rewrites, machinist not ported so some performance-specialized encodings still lack a Scala 3 equivalent, and http4s/Monix need active migration.
AI-written summary · about
chapters (28)
- 0:00Introduction
- 1:12Overview
- 1:54What is Typelevel
- 2:17Typelevel projects
- 3:09Typelevel origins
- 3:32Functional programming
- 4:35Type classes
- 6:30Encoding
- 8:50simulacrum
- 10:34Stimulac
- 13:08machinist
- 14:24cats
- 16:18Regular Polymorphism
- 17:36Type Constructor Polymorphism
- 18:43Type Lambda
- 19:48Time Protector
- 20:29SI2712
- 20:55SI2712 example
- 21:40Unapply
- 22:25Type parameter business
- 23:10Finally
- 23:45Type lenders
- 24:20Type system of Dottie
- 26:18Macros
- 26:47Scala 2 Macros
- 29:10Scala 2 ReImplementation
- 29:55Brief Outlook
- 30:06Release Candidate 1
