Deno 2

Deno 2 Python 3.13 TCL 9.0

Full of surprises this October

Question for those who use Deno in their $job: How well does Jest work with Deno to test TypeScript? I was wondering because the announcement says it supports typescript natively, which is intriguing after I've had issues with node+jest+es6+typescript.

(Issues = mts vs ts, configuration problems, lots of conflicting documentation. It doesn't help that I'm mostly DevOps and don't spend every day on writing Lambdas for AWS etc)

Edited to add: The installation page[1] talks about asdf[2] but I find mise-en-place[3] to be faster than asdf.

1: https://docs.deno.com/runtime/getting_started/installation/

2: https://asdf-vm.com/

3: https://mise.jdx.dev/

Mise/asdf are pretty great. A .tool-versions file in your homedir will set up default versions, and you can override them with .tool-versions in your repos. And because 2 different tools can read those versioning files, you can include them in the repo and pin versions.

Deno 2 with full Node compatibility is huge, presupposed it works reliably without runtime surprises. I wouldn't mind if I get a warning when a Node package is not supported, but runtime must be rock solid, especially with server packages like node-postgres (pg).

Apart from this little doubt, I love it:

The APIs and std lib are so extensive that we don't need huge amounts of third party packages. Typescript support is great. Deno actually can check Typescript (not just run it by stripping it as Node or Bun). Compiling (bundling) is another great feature.

I've started using Deno for some small hobby scripts and projects, and it's been really good so far. Their LSP server and VSCode extension are way faster and better than the default one, and configuration for a new project is much easier. Plus all the things like `deno fmt`. In comparison Bun only ships the runtime, without any of the tooling niceties.

I think I wouldn't use TypeScript without Deno now :)

Well done, the Deno team!

I found the FAQ in the announcement well made too, with some good and questions and answers.

I'm already having a great time with Deno v1 on my side project - thank you!