Tailwind v4 + NativeWind v5: HMR doesn’t pick up new classes in Expo app unless they existed at build time

[Vikum-AI]

Title: Tailwind v4 + NativeWind v5: HMR doesn’t pick up new classes in Expo app unless they existed at build time

Hi 👋
I’m running into a Hot Module Reloading issue with the Expo app generated from this repo when using Tailwind CSS v4 + NativeWind v5.

Context

• Template: t3-oss/create-t3-turbo (Expo app in apps/expo)
• Stack (from the template): Expo SDK 54, React Native 0.81, React 19
• Styling: Tailwind CSS v4 with NativeWind v5
• Tailwind is wired up via the default src/styles.css setup

What I’m seeing

When I add a new Tailwind class to a component in the Expo app, HMR doesn’t apply the new style unless that class was already present somewhere at build time.

Example:

Start dev server from repo root:

pnpm dev

Open apps/expo/src/app/index.tsx (or any screen) and add a brand-new Tailwind utility, e.g. change:

<View className="bg-background">

to:

<View className="bg-background border-4 border-red-500">

Save the file.

Expected behavior

Expo + NativeWind HMR should pick up the new Tailwind class (border-4 border-red-500) and update the UI immediately, without needing to restart the dev server.

Actual behavior

The component re-renders, but the new Tailwind class is ignored:

• If that class never existed at build time, it doesn’t take effect.
• If I restart the Expo dev server (or rebuild), the class suddenly works.

So it feels like the Tailwind transform only “sees” classes that were present when the dev server first started, and isn’t re-scanning files properly for new ones during HMR.

Notes / Workarounds

• Editing text or non-Tailwind props hot-reloads correctly — so HMR itself is working.
• The problem seems specific to new Tailwind utility classes added after the initial build.
• The only reliable workaround right now is to restart the Expo dev server every time I introduce a new Tailwind class.

Questions

• Is this a known limitation/bug with the current Tailwind v4 + NativeWind v5 + Expo setup in this template?
• Is there any recommended configuration tweak (e.g. @source setup, Tailwind/Metro integration, etc.) that would make Tailwind re-scan classes on HMR for the Expo app?
• If this is expected with Tailwind v4’s new pipeline, is there a suggested pattern (safelist, @source inline, etc.) you’d recommend for this repo specifically?

[lpwprojects]

I'm encountering the same issue, but restarting the expo dev server is not enough for me, it looks like I need to clear the cache as well. Anything new about the root cause or workaround?

[clicktodev]

i think this should be an issue instead of a discussion

[kingsleydon]

Remove the cacheStores snippet from metro.config.js works for me

config.cacheStores = [
  new FileStore({
    root: path.join(__dirname, "node_modules", ".cache", "metro"),
  }),
];