Fix PostCSS packaging and fixture compatibility

packages/core/__tests__/e2e/next-ssr.spec.js

@@ -251,8 +251,8 @@ test.describe('Zero-UI Comprehensive Test Suite', () => {
 		await expect(themeTest).toHaveCSS('background-color', 'rgb(0, 0, 0)'); // black
 
 		// Color styling
-		await expect(colorTest).toHaveCSS('background-color', 'oklch(0.637 0.237 25.331)'); // red-500
+		await expect(colorTest).toHaveCSS('background-color', 'lab(55.4814 75.0732 48.8528)'); // red-500
 		await page.getByTestId('color-blue').click();
-		await expect(colorTest).toHaveCSS('background-color', 'oklch(0.623 0.214 259.815)'); // blue-500
+		await expect(colorTest).toHaveCSS('background-color', 'lab(54.1736 13.3369 -74.6839)'); // blue-500
 	});
 });

packages/core/__tests__/fixtures/next/next-env.d.ts

@@ -1,5 +1,6 @@
 /// <reference types="next" />
 /// <reference types="next/image-types/global" />
+import "./.next/types/routes.d.ts";
 
 // NOTE: This file should not be edited
 // see https://nextjs.org/docs/app/api-reference/config/typescript for more information.

packages/core/__tests__/fixtures/next/package.json

@@ -8,17 +8,17 @@
     "clean": "rm -rf .next node_modules package-lock.json"
   },
   "dependencies": {
-    "next": "15.0.7",
-    "react": "^18.2.0",
-    "react-dom": "^18.2.0"
+    "next": "16.2.2",
+    "react": "19.2.4",
+    "react-dom": "19.2.4"
   },
   "devDependencies": {
-    "@tailwindcss/postcss": "^4.1.10",
+    "@tailwindcss/postcss": "4.2.2",
     "@types/node": "24.0.0",
-    "@types/react": "19.1.7",
+    "@types/react": "19.2.14",
     "eslint-plugin-react-zero-ui": "0.0.1-beta.1",
-    "postcss": "^8.5.5",
-    "tailwindcss": "^4.1.10",
+    "postcss": "8.5.8",
+    "tailwindcss": "4.2.2",
     "typescript": "5.8.3"
   }
 }

packages/core/__tests__/fixtures/next/tsconfig.json

@@ -7,15 +7,15 @@
     ],
     "allowJs": true,
     "skipLibCheck": true,
-    "strict": false,
+    "strict": true,
     "noEmit": true,
     "incremental": true,
     "module": "ESNext",
     "esModuleInterop": true,
     "moduleResolution": "bundler",
     "resolveJsonModule": true,
     "isolatedModules": true,
-    "jsx": "preserve",
+    "jsx": "react-jsx",
     "plugins": [
       {
         "name": "next"
@@ -35,7 +35,8 @@
     ".next/**/*.d.ts",
     ".next/types/**/*.ts",
     ".zero-ui/**/*.d.ts",
-    "next-env.d.ts"
+    "next-env.d.ts",
+    ".next/dev/types/**/*.ts"
   ],
   "exclude": [
     "node_modules"

packages/core/__tests__/fixtures/vite/package.json

@@ -9,17 +9,17 @@
 		"build-and-preview": "vite build && vite preview --port 5173"
 	},
 	"dependencies": {
-		"react": "^19.1.0",
-		"react-dom": "^19.1.0"
+		"react": "19.2.4",
+		"react-dom": "19.2.4"
 	},
 	"devDependencies": {
-		"@tailwindcss/postcss": "^4.1.10",
-		"@types/react": "^19.1.2",
-		"@types/react-dom": "^19.1.2",
-		"@vitejs/plugin-react": "^4.4.1",
-		"postcss": "^8.5.5",
-		"tailwindcss": "^4.1.10",
+		"@tailwindcss/postcss": "4.2.2",
+		"@types/react": "19.2.14",
+		"@types/react-dom": "19.2.3",
+		"@vitejs/plugin-react": "6.0.1",
+		"postcss": "8.5.8",
+		"tailwindcss": "4.2.2",
 		"typescript": "~5.8.3",
-		"vite": "^6.3.5"
+		"vite": "8.0.3"
 	}
 }

packages/core/__tests__/unit/index.test.cjs

@@ -96,6 +96,35 @@ test('generates body attributes file correctly', async () => {
 	);
 });
 
+test('warns instead of auto-initializing when project setup is missing', async () => {
+	await runTest(
+		{
+			'app/test.jsx': `
+      import { useUI } from '@react-zero-ui/core';
+
+      function Component() {
+        const [theme, setTheme] = useUI('theme', 'light');
+        return <div>Test</div>;
+      }
+    `,
+		},
+		(result) => {
+			assert(fs.existsSync(getAttrFile()), 'Attributes file should still be generated');
+			assert(!fs.existsSync('postcss.config.js'), 'PostCSS plugin should not create postcss.config.js');
+			assert(!fs.existsSync('postcss.config.mjs'), 'PostCSS plugin should not create postcss.config.mjs');
+			assert(!fs.existsSync('tsconfig.json'), 'PostCSS plugin should not patch tsconfig');
+
+			const warnings = result.warnings().map((warning) => warning.text);
+			assert(
+				warnings.some(
+					(text) => text.includes('Zero UI is not initialized') && text.includes('react-zero-ui')
+				),
+				'Expected a setup warning instead of auto-initialization'
+			);
+		}
+	);
+});
+
 test('generates body attributes file correctly when kebab-case is used', async () => {
 	await runTest(
 		{

packages/core/src/index.ts

@@ -1,10 +1,10 @@
 'use client';
-import { useRef, type RefObject } from 'react';
+import { useRef } from 'react';
 import { cssVar, makeSetter } from './internal.js';
 
 type UIAction<T extends string> = T | ((prev: T) => T);
 
-type ScopedRef = RefObject<HTMLElement | null> | (((node: HTMLElement | null) => void) & { current: HTMLElement | null });
+type ScopedRef = ((node: HTMLElement | null) => void) & { current: HTMLElement | null };
 
 interface ScopedSetterFn<T extends string = string> {
 	(action: UIAction<T>): void; //  ← SINGLE source of truth
@@ -22,40 +22,38 @@ function useScopedUI<T extends string = string>(key: string, initialValue: T, fl
 	// Create a ref to hold the DOM element that will receive the data-* attributes
 	// This allows scoping UI state to specific elements instead of always using document.body
 	const scopeRef = useRef<HTMLElement | null>(null);
-
 	const setterFn = useRef(makeSetter(key, initialValue, () => scopeRef.current!, flag)).current as ScopedSetterFn<T>;
-
-	if (process.env.NODE_ENV !== 'production') {
-		//  -- DEV-ONLY MULTIPLE REF GUARD (removed in production by modern bundlers)  --
-		// Attach the ref to the setter function so users can write: <div ref={setterFn.ref} />
-		const refAttachCount = useRef(0);
-		// DEV: Wrap scopeRef to detect multiple attachments
-		const attachRef = ((node: HTMLElement | null) => {
-			if (node) {
-				refAttachCount!.current++;
-				if (refAttachCount!.current > 1) {
-					// TODO add documentation link
-					throw new Error(
-						`[useUI] Multiple ref attachments detected for key "${key}". ` +
-							`Each useScopedUI hook supports only one ref attachment per component. ` +
-							`Solution: Create separate component. and reuse.\n` +
-							`React Strict Mode May Cause the Ref to be attached multiple times.`
-					);
+	const refAttachCount = useRef(0);
+	const attachRef = useRef<ScopedRef | null>(null);
+
+	if (!attachRef.current) {
+		attachRef.current = ((node: HTMLElement | null) => {
+			if (process.env.NODE_ENV !== 'production') {
+				if (node) {
+					refAttachCount.current++;
+					if (refAttachCount.current > 1) {
+						// TODO add documentation link
+						throw new Error(
+							`[useUI] Multiple ref attachments detected for key "${key}". ` +
+								`Each useScopedUI hook supports only one ref attachment per component. ` +
+								`Solution: Create separate component. and reuse.\n` +
+								`React Strict Mode May Cause the Ref to be attached multiple times.`
+						);
+					}
+				} else {
+					// Handle cleanup when ref is detached
+					refAttachCount.current = Math.max(0, refAttachCount.current - 1);
 				}
-			} else {
-				// Handle cleanup when ref is detached
-				refAttachCount!.current = Math.max(0, refAttachCount!.current - 1);
 			}
+
 			scopeRef.current = node;
-			attachRef.current = node;
-		}) as ((node: HTMLElement | null) => void) & { current: HTMLElement | null };
-		attachRef.current = null;
-		(setterFn as ScopedSetterFn<T>).ref = attachRef;
-	} else {
-		// PROD: Direct ref assignment for zero overhead
-		setterFn.ref = scopeRef;
+			attachRef.current!.current = node;
+		}) as ScopedRef;
+		attachRef.current.current = null;
 	}
 
+	setterFn.ref = attachRef.current;
+
 	// Return tuple matching React's useState pattern: [initialValue, setter]
 	return [initialValue, setterFn];
 }

packages/core/src/postcss/index.cts

@@ -2,21 +2,60 @@
 /**
  * @type {import('postcss').PluginCreator}
  */
-import { buildCss, generateAttributesFile, isZeroUiInitialized } from './helpers';
-import { runZeroUiInit } from '../cli/postInstall.js';
-import { processVariants } from './ast-parsing';
-import { CONFIG } from '../config';
-import { formatError, registerDeps, Result } from './utilities.js';
-
 type Root = { prepend: (css: string) => void };
+type Result = {
+	messages: { type: string; plugin: string; file: string; parent: string }[];
+	opts: { from: string };
+	prepend: (css: string) => void;
+	warn: (message: string, options?: { endIndex?: number; index?: number; node?: Node; plugin?: string; word?: string }) => void;
+};
+type RuntimeModules = {
+	buildCss: typeof import('./helpers.js').buildCss;
+	generateAttributesFile: typeof import('./helpers.js').generateAttributesFile;
+	isZeroUiInitialized: typeof import('./helpers.js').isZeroUiInitialized;
+	processVariants: typeof import('./ast-parsing.js').processVariants;
+	formatError: typeof import('./utilities.js').formatError;
+	registerDeps: typeof import('./utilities.js').registerDeps;
+};
+
+const zeroUIPlugin = 'postcss-react-zero-ui';
+const warnedCwds = new Set<string>();
+let runtimeModulesPromise: Promise<RuntimeModules> | null = null;
+
+function loadRuntimeModules(): Promise<RuntimeModules> {
+	if (!runtimeModulesPromise) {
+		runtimeModulesPromise = Promise.all([import('./helpers.js'), import('./ast-parsing.js'), import('./utilities.js')]).then(
+			([helpers, astParsing, utilities]) => ({
+				buildCss: helpers.buildCss,
+				generateAttributesFile: helpers.generateAttributesFile,
+				isZeroUiInitialized: helpers.isZeroUiInitialized,
+				processVariants: astParsing.processVariants,
+				formatError: utilities.formatError,
+				registerDeps: utilities.registerDeps,
+			})
+		);
+	}
 
-const zeroUIPlugin = CONFIG.PLUGIN_NAME;
+	return runtimeModulesPromise;
+}
+
+function warnIfNotInitialized(result: Result, isZeroUiInitialized: RuntimeModules['isZeroUiInitialized']) {
+	const cwd = process.cwd();
+
+	if (isZeroUiInitialized() || warnedCwds.has(cwd)) {
+		return;
+	}
+
+	warnedCwds.add(cwd);
+	result.warn('[Zero-UI] Zero UI is not initialized. Run `react-zero-ui` to patch your project config.', { plugin: zeroUIPlugin });
+}
 
 const plugin = () => {
 	return {
 		postcssPlugin: zeroUIPlugin,
 		async Once(root: Root, { result }: { result: Result }) {
 			try {
+				const { buildCss, generateAttributesFile, isZeroUiInitialized, processVariants, formatError, registerDeps } = await loadRuntimeModules();
 				const { finalVariants, initialGlobalValues, sourceFiles } = await processVariants();
 
 				const cssBlock = buildCss(finalVariants);
@@ -25,13 +64,10 @@ const plugin = () => {
 				/* ── register file-dependencies for HMR ─────────────────── */
 				registerDeps(result, zeroUIPlugin, sourceFiles, result.opts.from ?? '');
 
-				/* ── first-run bootstrap ────────────────────────────────── */
-				if (!isZeroUiInitialized()) {
-					console.log('[Zero-UI] Auto-initializing (first-time setup)…');
-					await runZeroUiInit();
-				}
+				warnIfNotInitialized(result, isZeroUiInitialized);
 				await generateAttributesFile(finalVariants, initialGlobalValues);
 			} catch (err: unknown) {
+				const { formatError, registerDeps } = await loadRuntimeModules();
 				const { friendly, loc } = formatError(err);
 				if (process.env.NODE_ENV !== 'production') {
 					if (loc?.file) registerDeps(result, zeroUIPlugin, [loc.file], result.opts.from ?? '');