TypeScript has the same; the whole type checker is in one massive file with 46,393 lines: https://github.com/microsoft/TypeScript/blob/main/src/compiler/checker

TypeScript has the same; the whole type checker is in one massive file with 46,393 lines: https://github.com/microsoft/TypeScript/blob/main/src/compiler/checker.ts https://github.com/microsoft/TypeScript/blob/main/src/compil... IIRC they cited performance reasons when compiling the compiler for the decision not to split the file up, but I could be wrong on this.