Utility classes not included in the production CSS

[magnum]

I am developing an application using Rails, Tailwind 4, and deploying it with Kamal.

Gem versions:

rails 8.0.2 
tailwindcss-rails (4.2.2)
tailwindcss-ruby (4.1.3)
kamal (2.5.3)

When I run the application locally, it functions correctly. However, after deploying it with Kamal, the Tailwind CSS included in the image does not contain utility classes such as px-<number>, opacity-<number>, gap-<number>, h-<number>, top-<number>, and bottom-<number>, even though other similar classes appear to be present.

Here are the steps I have taken so far:

• Verified that all classes are used directly within the template files (e.g., building them in Ruby, etc.).
• Built remotely with Kamal using an AMD64 architecture.

here're the two different built files

tailwind-development.css.txt
tailwind-production.css.txt

Any suggestions?

[powersurge360]

Also experiencing this. No idea what's causing it. @magnum what kind of jsbundling are you using? I'm experiencing this w/ esbuild.

[powersurge360]

I am willing to bet it's something along the lines of this #499 (comment)

ETA: Unbelievably, this seems to be the case. I decided to use the remote builder feature of kamal and reuse the same server that is hosting the application, and these properties began working. Woof.

[magnum]

@powersurge360 i'm using propshaft,
A few days ago, I attempted the remote build in Kamal, but I was unsuccessful. I just tried again, and it worked! I have made several attempts since then, and perhaps something has changed. However, I had tried many different approaches over the past few days and was losing hope. 🙂

It has been confirmed that the issue seems to be related to the architecture on which the Kamal build is based, as mentioned in #499 (comment).

[jspooner]

Also experiencing this. My app was deploying perfectly two days ago but is broken today.

[alvincrespo]

Same here. Both mb-4 and p-2 were problematic. Removed them and it builds successfully.

[dalink]

Same for me. Works well in devlopment, missing utility class in production

[dalink]

I am willing to bet it's something along the lines of this #499 (comment)

ETA: Unbelievably, this seems to be the case. I decided to use the remote builder feature of kamal and reuse the same server that is hosting the application, and these properties began working. Woof.

Your right, deployment if fine when building on the server via remote: ssh://docker@docker-builder.
I'am using a MacBook pro M1 and the target is an amd64 server

[flavorjones]

A few folks have referenced my comment in #499 where I ask someone experiencing this issue to report it upstream to tailwindlabs/tailwindcss. To my knowledge, noone has done this yet, and so I expect people to continue to have problems unless and until it's reported upstream and fixed there.

Can someone please open an issue at https://github.com/tailwindlabs/tailwindcss providing a reproduction and describing your experience? Thank you.

Since I'm more convinced now that the issue is upstream, I'm going to close this and redirect readers to #499 for further discussion.

[flavorjones]

Closing the loop, an upstream issue has been opened at tailwindlabs/tailwindcss#17728