[v4] Trouble updating to latest (from alpha 17) tailwindcss + @tailwindcss/postcss in a Laravel (vite) app

[nathangross]

I have been using Tailwind v4 (postcss) through alpha 17 just fine. It seems like something changed that is breaking my setup—but I can't figure out what it was. The release notes for the alphas were pretty sparse in the earlier alphas.

When I try to update these to any alpha after 17

"@tailwindcss/postcss": "^4.0.0-alpha.26",
"tailwindcss": "^4.0.0-alpha.26"

I get this error:

[vite] Internal server error: [postcss] (0 , p.compile) is not a function
  Plugin: vite:css

Any ideas?

[philipp-spiess]

@nathangross Hey! This issue usually indicates that one of the dependencies is not on the right version (we had a breaking change in one of the internal APIs in previous alpha versions, so it's important all of the alpha releases match up). Can you check what your resolved versions of tailwindcss and @tailwindcss/postcss point to by doing something like this?

cat node_modules/tailwindcss/package.json 
cat node_modules/@tailwindcss/postcss/package.json 

Alternatively you could take a look at the lockfile of your package manager.