[madeofpalk]

> Ezno's type checker is built from scratch. Getting the features I wanted requires a lot of different functionality and needed several new ideas that as far as I know aren't present in any type-system or existing checkers.

I would disagree this is a TypeScript compiler. It's a mostly-typescript-compatible compiler/type-checker.

The Typescript team iterate on it reasonably quickly. If you fall behind as the Typescript team adds new features, and you cannot check that code, is it still "Typescript"?

[anamexis]

The author himself does not call it a TypeScript compiler.

[madeofpalk]

That is actually completely fair - I still had OP's editorialized headline in mind when reading the site, and didn't notice all it says about typescript is "The checker is fully compatible with TypeScript type annotations" which is probably fair!

[yencabulator]

The author states

> The checker is fully compatible with TypeScript type annotations and can work without any type annotations at all.

That should at least be guarded with a version number, then.