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The nightlies gap is real. The stable release cycle means a lot of useful API surface sits in beta for months before it ships, and most people never look at what's actually available there.

I think 100% of what I showed actually shipped in 7.0. We haven’t talked about it a ton because we’re kind of at full capacity implementing things we know still need to get done, so I wanted to be a little strategic about the volume of feedback we get. Bit it’s time to start expanding a bit more.

I depend on Typescript 5 for an ECMAScript ahead-of-time compiler @js2wasm.bsky.social and use the programmatic API for type checking and other things and hope to get some speedups with TS 7. How will performance be for programmatic API use?

And can TS7 including the API be compiled as WebAssembly already?

Not yet. As for perf, it depends. The more separate requests, the more IPC overhead adds up. Wasm builds bring their own perf penalty to Go. I’ve seen tools get faster, stay the same, and get slower after moving to TS 7.

The API comes in sync and async flavors. You import from "unstable" for now, but it's not going to change architecturally before 7.1. Breaks will be mostly targeted renames/moves. You access programs through obtaining immutable snapshots. There will be more ways coming soon. More on this later.

Let’s start with something basic like getting diagnostics. Not too much to say about this. Each API call like this is communicating over STDIO with the tsgo process. We'll see some details in a minute.

Slightly more interesting: let's navigate a source file and use the type checker on some stuff. This found the return type 'void' from `console.log` and the return type 'number' from `add`.