The main Salt repo is here:
If you're using VSCode then there is a matching extension for it, which includes the required syntax definition and TypeScript shim to talk to the language server:
I’ve also made light and dark VSCode themes that know more about how to highlight Salt code than the standard ones. These themes have also been fixed to work with the standard VSCode Haskell syntax definitions, and I now use them for my main development. Note that these themes are not strictly required to use the above language server, as the standard ones also work well enough.
Installation of the VSCode things is currently manual as I haven’t pushed the extensions to the VSCode marketplace. I’ll do that once they’ve matured a bit more.
There are some screenshots on the GitHub pages for the last two repos.