diff --git a/CHANGELOG.md b/CHANGELOG.md
index 29652aa4d..d590b614d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,7 +7,9 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ## [Unreleased]
 
-- Nothing yet!
+### Fixed
+
+- Bring back type exports for the cjs build of `@tailwindcss/postcss`. ([#14256](https://github.com/tailwindlabs/tailwindcss/pull/14256))
 
 ## [4.0.0-alpha.20] - 2024-08-23
 
diff --git a/packages/@tailwindcss-postcss/src/index.cts b/packages/@tailwindcss-postcss/src/index.cts
new file mode 100644
index 000000000..abc7c2e25
--- /dev/null
+++ b/packages/@tailwindcss-postcss/src/index.cts
@@ -0,0 +1,7 @@
+import tailwindcss from './index.ts'
+
+// This is used instead of `export default` to work around a bug in
+// `postcss-load-config`
+
+// @ts-ignore
+export = tailwindcss
diff --git a/packages/@tailwindcss-postcss/src/index.ts b/packages/@tailwindcss-postcss/src/index.ts
index af1ca44b1..2e2641ada 100644
--- a/packages/@tailwindcss-postcss/src/index.ts
+++ b/packages/@tailwindcss-postcss/src/index.ts
@@ -29,7 +29,7 @@ class DefaultMap<T = string, V = any> extends Map<T, V> {
   }
 }
 
-type PluginOptions = {
+export type PluginOptions = {
   // The base directory to scan for class candidates.
   base?: string
 
@@ -209,5 +209,4 @@ function optimizeCss(
   }).code.toString()
 }
 
-// This is used instead of `export default` to work around a bug in `postcss-load-config`
-module.exports = Object.assign(tailwindcss, { postcss: true }) as PluginCreator<PluginOptions>
+export default Object.assign(tailwindcss, { postcss: true }) as PluginCreator<PluginOptions>
diff --git a/packages/@tailwindcss-postcss/tsup.config.ts b/packages/@tailwindcss-postcss/tsup.config.ts
index 70094ff8a..76e4fc03b 100644
--- a/packages/@tailwindcss-postcss/tsup.config.ts
+++ b/packages/@tailwindcss-postcss/tsup.config.ts
@@ -1,11 +1,20 @@
 import { defineConfig } from 'tsup'
 
-export default defineConfig({
-  format: ['esm', 'cjs'],
-  clean: true,
-  minify: true,
-  cjsInterop: true,
-  dts: true,
-  entry: ['src/index.ts'],
-  noExternal: ['internal-postcss-fix-relative-paths'],
-})
+export default defineConfig([
+  {
+    format: ['esm'],
+    minify: true,
+    cjsInterop: true,
+    dts: true,
+    entry: ['src/index.ts'],
+    noExternal: ['internal-postcss-fix-relative-paths'],
+  },
+  {
+    format: ['cjs'],
+    minify: true,
+    cjsInterop: true,
+    dts: true,
+    entry: ['src/index.cts'],
+    noExternal: ['internal-postcss-fix-relative-paths'],
+  },
+])
diff --git a/packages/tailwindcss/src/compat/colors.cts b/packages/tailwindcss/src/compat/colors.cts
index 34d90e1e9..b903bf39b 100644
--- a/packages/tailwindcss/src/compat/colors.cts
+++ b/packages/tailwindcss/src/compat/colors.cts
@@ -1 +1,4 @@
-module.exports = require('./colors.ts').default
+import colors from './colors.ts'
+
+// @ts-ignore
+export = colors
diff --git a/packages/tailwindcss/src/compat/default-theme.cts b/packages/tailwindcss/src/compat/default-theme.cts
index bc1750d7e..235d60252 100644
--- a/packages/tailwindcss/src/compat/default-theme.cts
+++ b/packages/tailwindcss/src/compat/default-theme.cts
@@ -1 +1,4 @@
-module.exports = require('./default-theme.ts').default
+import defaultTheme from './default-theme.ts'
+
+// @ts-ignore
+export = defaultTheme
diff --git a/packages/tailwindcss/src/plugin.cts b/packages/tailwindcss/src/plugin.cts
index e7000e927..f7bf734ed 100644
--- a/packages/tailwindcss/src/plugin.cts
+++ b/packages/tailwindcss/src/plugin.cts
@@ -1,5 +1,8 @@
-// This file exists so that `plugin.ts` can be written one time but be compatible with both CJS and
-// ESM. Without it we get a `.default` export when using `require` in CJS.
+import plugin from './plugin.ts'
+
+// This file exists so that `plugin.ts` can be written one time but be
+// compatible with both CJS and ESM. Without it we get a `.default` export when
+// using `require` in CJS.
 
 // @ts-ignore
-module.exports = require('./plugin.ts').default
+export = plugin
diff --git a/playgrounds/nextjs/postcss.config.js b/playgrounds/nextjs/postcss.config.js
index 6c434006e..d70796632 100644
--- a/playgrounds/nextjs/postcss.config.js
+++ b/playgrounds/nextjs/postcss.config.js
@@ -1,3 +1,5 @@
+import tailwindcss from '@tailwindcss/postcss'
+
 module.exports = {
-  plugins: ['@tailwindcss/postcss'],
+  plugins: [tailwindcss()],
 }