From 558b16ca0b7f45e93f512a570757f2044a3ceec1 Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 13:57:51 +0800
Subject: [PATCH 1/8] fix(pack): bundle @tsdown/exe and @tsdown/css into core

@tsdown/exe and @tsdown/css hard-peer-depend on tsdown and import
tsdown/internal, but Vite+ bundles tsdown internally with no resolvable
top-level tsdown package, so installing them failed with "Failed to
import module @tsdown/exe".

Bundle both into core (tsdown-exe.js, tsdown-css.js) so they resolve
tsdown/internal at build time and work without any extra install.
lightningcss (native) stays external as an optional peer, loaded lazily
with an actionable error when it is missing.

Closes #1586
---
 docs/guide/pack.md                            |  16 ++
 .../snap-tests/command-pack-css/package.json  |   5 +
 .../cli/snap-tests/command-pack-css/snap.txt  |  16 ++
 .../snap-tests/command-pack-css/src/index.ts  |   3 +
 .../snap-tests/command-pack-css/src/style.css |   7 +
 .../snap-tests/command-pack-css/steps.json    |   7 +
 .../package.json                              |   5 +
 .../command-pack-tsdown-extensions/snap.txt   |   3 +
 .../command-pack-tsdown-extensions/steps.json |   6 +
 .../verify-extensions.mjs                     |  22 +++
 packages/core/build.ts                        | 151 ++++++++++++++++--
 packages/core/package.json                    |  16 +-
 pnpm-lock.yaml                                |  24 +--
 pnpm-workspace.yaml                           |   2 +
 rfcs/pack-command.md                          |  64 +++++++-
 15 files changed, 311 insertions(+), 36 deletions(-)
 create mode 100644 packages/cli/snap-tests/command-pack-css/package.json
 create mode 100644 packages/cli/snap-tests/command-pack-css/snap.txt
 create mode 100644 packages/cli/snap-tests/command-pack-css/src/index.ts
 create mode 100644 packages/cli/snap-tests/command-pack-css/src/style.css
 create mode 100644 packages/cli/snap-tests/command-pack-css/steps.json
 create mode 100644 packages/cli/snap-tests/command-pack-tsdown-extensions/package.json
 create mode 100644 packages/cli/snap-tests/command-pack-tsdown-extensions/snap.txt
 create mode 100644 packages/cli/snap-tests/command-pack-tsdown-extensions/steps.json
 create mode 100644 packages/cli/snap-tests/command-pack-tsdown-extensions/verify-extensions.mjs

diff --git a/docs/guide/pack.md b/docs/guide/pack.md
index b1714c48df..18c70cf6ab 100644
--- a/docs/guide/pack.md
+++ b/docs/guide/pack.md
@@ -58,4 +58,20 @@ export default defineConfig({
 });
 ```
 
+Executable support is bundled into Vite+, so you do not need to install `@tsdown/exe` separately.
+
+Building executables uses Node's [Single Executable Applications](https://nodejs.org/api/single-executable-applications.html) support and requires Node.js 25.7.0 or later. Switch the active runtime with `vp env use 25` if `vp pack --exe` reports an unsupported version.
+
 See the official [tsdown executable docs](https://tsdown.dev/options/exe#executable) for details about configuring custom file names, embedded assets, and cross-platform targets.
+
+## CSS Bundling
+
+`vp pack` can transform and bundle CSS (including CSS Modules and Lightning CSS optimizations) for your entry points. This support is bundled into Vite+, so you do not need to install `@tsdown/css`.
+
+CSS transforms are powered by [Lightning CSS](https://lightningcss.dev/), which ships as a native module and is an optional peer dependency. Install it when you bundle CSS:
+
+```bash
+vp add -D lightningcss
+```
+
+If it is missing, `vp pack` prints an actionable error telling you to install it.
diff --git a/packages/cli/snap-tests/command-pack-css/package.json b/packages/cli/snap-tests/command-pack-css/package.json
new file mode 100644
index 0000000000..6b91fc3570
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "command-pack-css",
+  "version": "1.0.0",
+  "type": "module"
+}
diff --git a/packages/cli/snap-tests/command-pack-css/snap.txt b/packages/cli/snap-tests/command-pack-css/snap.txt
new file mode 100644
index 0000000000..a4b43ee8d9
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css/snap.txt
@@ -0,0 +1,16 @@
+> vp pack src/index.ts --minify # bundles CSS via the bundled @tsdown/css + lightningcss (issue #1586)
+ℹ entry: src/index.ts
+ℹ Build start
+ℹ dist/index.mjs  <variable> kB │ gzip: <variable> kB
+ℹ dist/style.css  <variable> kB │ gzip: <variable> kB
+ℹ 2 files, total: <variable> kB
+✔ Build complete in <variable>ms
+
+> cat dist/style.css # lightningcss-optimized output proves @tsdown/css ran
+.foo {
+  color: red;
+}
+
+.bar {
+  margin: 0;
+}
diff --git a/packages/cli/snap-tests/command-pack-css/src/index.ts b/packages/cli/snap-tests/command-pack-css/src/index.ts
new file mode 100644
index 0000000000..add68f6159
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css/src/index.ts
@@ -0,0 +1,3 @@
+import './style.css';
+
+export const hello = 'world';
diff --git a/packages/cli/snap-tests/command-pack-css/src/style.css b/packages/cli/snap-tests/command-pack-css/src/style.css
new file mode 100644
index 0000000000..d5aba93ecd
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css/src/style.css
@@ -0,0 +1,7 @@
+.foo {
+  color: #ff0000;
+}
+
+.bar {
+  margin: 0px 0px 0px 0px;
+}
diff --git a/packages/cli/snap-tests/command-pack-css/steps.json b/packages/cli/snap-tests/command-pack-css/steps.json
new file mode 100644
index 0000000000..437afe16f8
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css/steps.json
@@ -0,0 +1,7 @@
+{
+  "ignoredPlatforms": ["win32"],
+  "commands": [
+    "vp pack src/index.ts --minify # bundles CSS via the bundled @tsdown/css + lightningcss (issue #1586)",
+    "cat dist/style.css # lightningcss-optimized output proves @tsdown/css ran"
+  ]
+}
diff --git a/packages/cli/snap-tests/command-pack-tsdown-extensions/package.json b/packages/cli/snap-tests/command-pack-tsdown-extensions/package.json
new file mode 100644
index 0000000000..77cd0bb956
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-tsdown-extensions/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "command-pack-tsdown-extensions",
+  "version": "1.0.0",
+  "type": "module"
+}
diff --git a/packages/cli/snap-tests/command-pack-tsdown-extensions/snap.txt b/packages/cli/snap-tests/command-pack-tsdown-extensions/snap.txt
new file mode 100644
index 0000000000..af5ce06923
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-tsdown-extensions/snap.txt
@@ -0,0 +1,3 @@
+> node verify-extensions.mjs # bundled @tsdown/exe and @tsdown/css load without a top-level tsdown (issue #1586)
+tsdown-exe.js: getCacheDir, getCachedBinaryPath, getTargetSuffix, resolveNodeBinary
+tsdown-css.js: CssPlugin, resolveCssOptions
diff --git a/packages/cli/snap-tests/command-pack-tsdown-extensions/steps.json b/packages/cli/snap-tests/command-pack-tsdown-extensions/steps.json
new file mode 100644
index 0000000000..b00e80a479
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-tsdown-extensions/steps.json
@@ -0,0 +1,6 @@
+{
+  "ignoredPlatforms": ["win32"],
+  "commands": [
+    "node verify-extensions.mjs # bundled @tsdown/exe and @tsdown/css load without a top-level tsdown (issue #1586)"
+  ]
+}
diff --git a/packages/cli/snap-tests/command-pack-tsdown-extensions/verify-extensions.mjs b/packages/cli/snap-tests/command-pack-tsdown-extensions/verify-extensions.mjs
new file mode 100644
index 0000000000..93dbe6cdb1
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-tsdown-extensions/verify-extensions.mjs
@@ -0,0 +1,22 @@
+// Issue #1586: `@tsdown/exe` and `@tsdown/css` have a hard peer dependency on
+// `tsdown` and import `tsdown/internal`, but Vite+ bundles tsdown internally and
+// does not expose a resolvable top-level `tsdown` package. Before the fix, the
+// bundled tsdown loaded them as external top-level packages, so `vp pack --exe`
+// (and CSS bundling) failed with `Failed to import module "@tsdown/exe"`.
+//
+// They are now bundled into core, so this loads the bundled extension chunks
+// directly to prove they resolve `tsdown/internal` against the bundled tsdown.
+// `vp pack --exe` itself needs Node >= 25.7 (SEA), so it cannot run end-to-end
+// in CI; this check is Node-version independent.
+import { createRequire } from 'node:module';
+import path from 'node:path';
+import { pathToFileURL } from 'node:url';
+
+const require = createRequire(import.meta.url);
+const packEntry = require.resolve('@voidzero-dev/vite-plus-core/pack');
+const tsdownDir = path.dirname(packEntry);
+
+for (const chunk of ['tsdown-exe.js', 'tsdown-css.js']) {
+  const mod = await import(pathToFileURL(path.join(tsdownDir, chunk)).href);
+  console.log(`${chunk}: ${Object.keys(mod).sort().join(', ')}`);
+}
diff --git a/packages/core/build.ts b/packages/core/build.ts
index c44383c9c9..cd012a4106 100644
--- a/packages/core/build.ts
+++ b/packages/core/build.ts
@@ -1,5 +1,6 @@
 import { existsSync } from 'node:fs';
 import { copyFile, cp, mkdir, readFile, stat, writeFile } from 'node:fs/promises';
+import { createRequire } from 'node:module';
 import path from 'node:path';
 import { dirname, join, parse, resolve, relative } from 'node:path';
 import { fileURLToPath } from 'node:url';
@@ -54,6 +55,7 @@ await bundleRolldown();
 await buildVite();
 await bundleTsdown();
 await brandTsdown();
+await wireBundledTsdownExtensions();
 await bundleVitepress();
 generateLicenseFile({
   title: 'Vite-Plus core license',
@@ -379,23 +381,47 @@ async function bundleRolldown() {
 async function bundleTsdown() {
   await mkdir(join(projectDir, 'dist/tsdown/dist'), { recursive: true });
 
-  const tsdownExternal = Object.keys(pkgJson.peerDependencies);
+  const require = createRequire(import.meta.url);
+
+  // `@tsdown/exe` and `@tsdown/css` are bundled directly into core instead of
+  // being externalized. They have a hard peer dependency on `tsdown` and import
+  // `tsdown/internal`, but Vite+ bundles tsdown inside core rather than exposing
+  // a resolvable top-level `tsdown` package. Bundling them here resolves
+  // `tsdown/internal` against the bundled tsdown at build time, so `vp pack
+  // --exe` and CSS bundling work without users installing anything extra.
+  // See https://github.com/voidzero-dev/vite-plus/issues/1586
+  const bundledTsdownPackages = new Set(['@tsdown/exe', '@tsdown/css']);
+
+  // Everything else in tsdown's peer dependencies stays external. `lightningcss`
+  // (a native module) and `postcss` also stay external: `@tsdown/css` pulls them
+  // in, and they cannot be bundled. `lightningcss` becomes an optional peer with
+  // a friendly loader injected by `wireBundledTsdownExtensions()`.
+  const tsdownExternal = [
+    ...Object.keys(pkgJson.peerDependencies).filter((name) => !bundledTsdownPackages.has(name)),
+    'lightningcss',
+    'postcss',
+  ];
+  const isExternal = (id: string) => tsdownExternal.some((e) => id === e || id.startsWith(`${e}/`));
 
   const thirdPartyCjsModules = new Set<string>();
 
-  // Re-build tsdown cli
+  // Re-build tsdown cli plus the bundled `@tsdown/exe` and `@tsdown/css`
+  // extensions as stable named entries (`tsdown-exe.js`, `tsdown-css.js`).
   await build({
     input: {
       run: join(tsdownSourceDir, 'dist/run.mjs'),
       index: join(tsdownSourceDir, 'dist/index.mjs'),
+      'tsdown-exe': require.resolve('@tsdown/exe'),
+      'tsdown-css': require.resolve('@tsdown/css'),
     },
     output: {
       format: 'esm',
       cleanDir: true,
       dir: join(projectDir, 'dist/tsdown'),
+      entryFileNames: '[name].js',
     },
     platform: 'node',
-    external: (id: string) => tsdownExternal.some((e) => id.startsWith(e)),
+    external: isExternal,
     plugins: [
       RewriteImportsPlugin,
       {
@@ -425,7 +451,7 @@ async function bundleTsdown() {
       format: 'esm',
       dir: join(projectDir, 'dist/tsdown'),
     },
-    external: (id: string) => tsdownExternal.some((e) => id.startsWith(e)),
+    external: isExternal,
     plugins: [
       RewriteImportsPlugin,
       dts({
@@ -448,13 +474,14 @@ async function bundleTsdown() {
 async function brandTsdown() {
   const tsdownDistDir = join(projectDir, 'dist/tsdown');
   const buildFiles = await glob(toPosixPath(join(tsdownDistDir, 'build-*.js')), { absolute: true });
-  const mainFiles = await glob(toPosixPath(join(tsdownDistDir, 'main-*.js')), { absolute: true });
+  // The logger code lives in a shared chunk whose name depends on rolldown's
+  // chunking (e.g. `main-*.js` or `debug-*.js`), so scan every chunk for it.
+  const loggerCandidateFiles = await glob(toPosixPath(join(tsdownDistDir, '*.js')), {
+    absolute: true,
+  });
   if (buildFiles.length === 0) {
     throw new Error('brandTsdown: no build chunk found in dist/tsdown/');
   }
-  if (mainFiles.length === 0) {
-    throw new Error('brandTsdown: no main chunk found in dist/tsdown/');
-  }
 
   const search = '"tsdown <your-file>"';
   const replacement = '"vp pack <your-file>"';
@@ -534,8 +561,8 @@ async function brandTsdown() {
   ];
   let loggerPatched = false;
 
-  for (const mainFile of mainFiles) {
-    let content = await readFile(mainFile, 'utf-8');
+  for (const candidateFile of loggerCandidateFiles) {
+    let content = await readFile(candidateFile, 'utf-8');
     let changed = false;
     for (const { search, replacement } of loggerPatches) {
       if (content.includes(search)) {
@@ -546,13 +573,91 @@ async function brandTsdown() {
     if (!changed) {
       continue;
     }
-    await writeFile(mainFile, content, 'utf-8');
-    console.log(`Branded tsdown logger prefixes in ${mainFile}`);
+    await writeFile(candidateFile, content, 'utf-8');
+    console.log(`Branded tsdown logger prefixes in ${candidateFile}`);
     loggerPatched = true;
   }
 
   if (!loggerPatched) {
-    throw new Error('brandTsdown: logger prefix patterns not found in any main chunk');
+    throw new Error('brandTsdown: logger prefix patterns not found in any chunk');
+  }
+}
+
+// Wire the bundled `@tsdown/exe` and `@tsdown/css` extensions into the bundled
+// tsdown so they load from the local chunks instead of resolving external
+// top-level packages, and make `lightningcss` an optional peer with a friendly
+// loader. See https://github.com/voidzero-dev/vite-plus/issues/1586
+async function wireBundledTsdownExtensions() {
+  const tsdownDistDir = join(projectDir, 'dist/tsdown');
+  const buildFiles = await glob(toPosixPath(join(tsdownDistDir, 'build-*.js')), { absolute: true });
+  if (buildFiles.length === 0) {
+    throw new Error('wireBundledTsdownExtensions: no build chunk found in dist/tsdown/');
+  }
+
+  // 1) Route `@tsdown/exe` and `@tsdown/css` to the bundled entries.
+  //    - `importWithError("@tsdown/exe")` dynamically imports a runtime string,
+  //      which rolldown cannot follow, so rewrite the call site to the chunk.
+  //    - `pkgExists("@tsdown/css")` resolves the top-level package at runtime;
+  //      since it is bundled now, force it on and point the import at the chunk.
+  let exeWired = false;
+  let cssWired = false;
+  for (const buildFile of buildFiles) {
+    let content = await readFile(buildFile, 'utf-8');
+    let changed = false;
+    if (content.includes('importWithError("@tsdown/exe")')) {
+      content = content.replaceAll('importWithError("@tsdown/exe")', 'import("./tsdown-exe.js")');
+      exeWired = true;
+      changed = true;
+    }
+    if (content.includes('pkgExists("@tsdown/css")')) {
+      content = content.replaceAll('pkgExists("@tsdown/css")', 'true');
+      cssWired = true;
+      changed = true;
+    }
+    if (content.includes('import("@tsdown/css")')) {
+      content = content.replaceAll('import("@tsdown/css")', 'import("./tsdown-css.js")');
+      changed = true;
+    }
+    if (changed) {
+      await writeFile(buildFile, content);
+    }
+  }
+  if (!exeWired) {
+    throw new Error('wireBundledTsdownExtensions: `importWithError("@tsdown/exe")` not found');
+  }
+  if (!cssWired) {
+    throw new Error('wireBundledTsdownExtensions: `pkgExists("@tsdown/css")` not found');
+  }
+
+  // 2) `lightningcss` is a native module and an optional peer. Wrap its dynamic
+  //    import so a missing install produces an actionable error instead of a raw
+  //    `Cannot find package 'lightningcss'`.
+  const helper =
+    'async function __vpImportLightningcss() {\n' +
+    '  try {\n' +
+    '    return await import("lightningcss");\n' +
+    '  } catch (cause) {\n' +
+    '    throw new Error(' +
+    '"Cannot find package \\"lightningcss\\". CSS bundling with `vp pack` requires it. ' +
+    'Install it with `vp add -D lightningcss`.", { cause });\n' +
+    '  }\n' +
+    '}\n';
+  const allChunks = await glob(toPosixPath(join(tsdownDistDir, '*.js')), { absolute: true });
+  let lightningcssWired = false;
+  for (const chunk of allChunks) {
+    let content = await readFile(chunk, 'utf-8');
+    if (!content.includes('import("lightningcss")')) {
+      continue;
+    }
+    // Rewrite the call sites first, then prepend the helper (whose own
+    // `import("lightningcss")` must not be rewritten).
+    content = content.replaceAll('import("lightningcss")', '__vpImportLightningcss()');
+    content = helper + content;
+    await writeFile(chunk, content);
+    lightningcssWired = true;
+  }
+  if (!lightningcssWired) {
+    throw new Error('wireBundledTsdownExtensions: `import("lightningcss")` not found');
   }
 }
 
@@ -650,6 +755,14 @@ async function mergePackageJson() {
   const vitePkg = JSON.parse(await readFile(vitePkgPath, 'utf-8'));
   const destPkg = JSON.parse(await readFile(destPkgPath, 'utf-8'));
 
+  // Track the bundled `@tsdown/css` lightningcss dependency so the optional peer
+  // range stays in lockstep with what the bundled CSS code expects.
+  const require = createRequire(import.meta.url);
+  const tsdownCssPkg = JSON.parse(
+    await readFile(require.resolve('@tsdown/css/package.json'), 'utf-8'),
+  );
+  const lightningcssPeerRange: string = tsdownCssPkg.dependencies?.lightningcss ?? '^1.30.2';
+
   // Merge peerDependencies from tsdown and vite
   destPkg.peerDependencies = {
     ...tsdownPkg.peerDependencies,
@@ -662,6 +775,18 @@ async function mergePackageJson() {
     ...vitePkg.peerDependenciesMeta,
   };
 
+  // `@tsdown/exe` and `@tsdown/css` are bundled into core (see bundleTsdown),
+  // so they must not be advertised as peers anymore. `lightningcss` is a native
+  // module pulled in by the bundled `@tsdown/css` (and Vite's lightningcss
+  // transformer); keep it external as an optional peer so users only install it
+  // when they actually bundle CSS.
+  for (const bundled of ['@tsdown/exe', '@tsdown/css']) {
+    delete destPkg.peerDependencies[bundled];
+    delete destPkg.peerDependenciesMeta[bundled];
+  }
+  destPkg.peerDependencies['lightningcss'] = lightningcssPeerRange;
+  destPkg.peerDependenciesMeta['lightningcss'] = { optional: true };
+
   destPkg.bundledVersions = {
     ...destPkg.bundledVersions,
     vite: vitePkg.version,
diff --git a/packages/core/package.json b/packages/core/package.json
index 2920ac5fbd..eaa797872b 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -102,7 +102,6 @@
   "dependencies": {
     "@oxc-project/runtime": "catalog:",
     "@oxc-project/types": "catalog:",
-    "lightningcss": "^1.30.2",
     "postcss": "^8.5.6"
   },
   "devDependencies": {
@@ -112,9 +111,12 @@
     "@babel/types": "^7.28.5",
     "@oxc-node/cli": "catalog:",
     "@oxc-node/core": "catalog:",
+    "@tsdown/css": "catalog:",
+    "@tsdown/exe": "catalog:",
     "@vitejs/devtools": "^0.3.3",
     "es-module-lexer": "^1.7.0",
     "hookable": "^6.0.1",
+    "lightningcss": "^1.32.0",
     "magic-string": "^0.30.21",
     "oxc-parser": "catalog:",
     "oxfmt": "catalog:",
@@ -133,13 +135,12 @@
   },
   "peerDependencies": {
     "@arethetypeswrong/core": "^0.18.1",
-    "@tsdown/css": "0.22.3",
-    "@tsdown/exe": "0.22.3",
     "@types/node": "^20.19.0 || >=22.12.0",
     "@vitejs/devtools": "^0.1.18",
     "esbuild": "^0.27.0 || ^0.28.0",
     "jiti": ">=1.21.0",
     "less": "^4.0.0",
+    "lightningcss": "^1.32.0",
     "publint": "^0.3.8",
     "sass": "^1.70.0",
     "sass-embedded": "^1.70.0",
@@ -156,12 +157,6 @@
     "@arethetypeswrong/core": {
       "optional": true
     },
-    "@tsdown/css": {
-      "optional": true
-    },
-    "@tsdown/exe": {
-      "optional": true
-    },
     "@vitejs/devtools": {
       "optional": true
     },
@@ -209,6 +204,9 @@
     },
     "yaml": {
       "optional": true
+    },
+    "lightningcss": {
+      "optional": true
     }
   },
   "optionalDependencies": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 9958a548b6..97246307a8 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -51,6 +51,12 @@ catalogs:
     '@rollup/plugin-node-resolve':
       specifier: ^16.0.0
       version: 16.0.3
+    '@tsdown/css':
+      specifier: ^0.22.3
+      version: 0.22.3
+    '@tsdown/exe':
+      specifier: ^0.22.3
+      version: 0.22.3
     '@types/babel__core':
       specifier: 7.20.5
       version: 7.20.5
@@ -507,12 +513,6 @@ importers:
       '@oxc-project/types':
         specifier: 'catalog:'
         version: 0.136.0
-      '@tsdown/css':
-        specifier: 0.22.3
-        version: 0.22.3(jiti@2.7.0)(postcss-import@16.1.1(postcss@8.5.15))(postcss-modules@6.0.1(postcss@8.5.15))(postcss@8.5.15)(sass-embedded@1.100.0(source-map-js@1.2.1))(sass@1.100.0)(tsdown@0.22.3)(tsx@4.22.4)(yaml@2.9.0)
-      '@tsdown/exe':
-        specifier: 0.22.3
-        version: 0.22.3(tsdown@0.22.3)
       '@types/node':
         specifier: ^20.19.0 || >=22.12.0
         version: 24.12.4
@@ -525,9 +525,6 @@ importers:
       less:
         specifier: ^4.0.0
         version: 4.4.2
-      lightningcss:
-        specifier: ^1.30.2
-        version: 1.32.0
       postcss:
         specifier: ^8.5.6
         version: 8.5.15
@@ -583,6 +580,12 @@ importers:
       '@oxc-node/core':
         specifier: 'catalog:'
         version: 0.1.0
+      '@tsdown/css':
+        specifier: 'catalog:'
+        version: 0.22.3(jiti@2.7.0)(postcss-import@16.1.1(postcss@8.5.15))(postcss-modules@6.0.1(postcss@8.5.15))(postcss@8.5.15)(sass-embedded@1.100.0(source-map-js@1.2.1))(sass@1.100.0)(tsdown@0.22.3)(tsx@4.22.4)(yaml@2.9.0)
+      '@tsdown/exe':
+        specifier: 'catalog:'
+        version: 0.22.3(tsdown@0.22.3)
       '@vitejs/devtools':
         specifier: ^0.3.3
         version: 0.3.3(typescript@6.0.2)(vite@packages+core)
@@ -592,6 +595,9 @@ importers:
       hookable:
         specifier: ^6.0.1
         version: 6.1.1
+      lightningcss:
+        specifier: ^1.32.0
+        version: 1.32.0
       magic-string:
         specifier: ^0.30.21
         version: 0.30.21
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index ac9c9cde2d..7fafd253ba 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -23,6 +23,8 @@ catalog:
   '@rollup/plugin-commonjs': ^29.0.0
   '@rollup/plugin-json': ^6.1.0
   '@rollup/plugin-node-resolve': ^16.0.0
+  '@tsdown/css': ^0.22.3
+  '@tsdown/exe': ^0.22.3
   '@types/babel__core': 7.20.5
   '@types/connect': ^3.4.38
   '@types/cross-spawn': ^6.0.6
diff --git a/rfcs/pack-command.md b/rfcs/pack-command.md
index 2a938f1e24..4693aeac7c 100644
--- a/rfcs/pack-command.md
+++ b/rfcs/pack-command.md
@@ -201,6 +201,40 @@ tsdown is bundled inside `@voidzero-dev/vite-plus-core/pack`:
 - `packages/core/package.json` tracks `bundledVersions.tsdown`
 - Re-exported via `packages/cli/src/pack.ts`
 
+The `@tsdown/exe` (executables) and `@tsdown/css` (CSS bundling) extensions are
+bundled alongside tsdown as well, so `vp pack --exe` and CSS bundling work
+without users installing anything extra. See [tsdown Extensions](#bundled-tsdown-extensions).
+
+### Bundled tsdown Extensions
+
+This covers the `@tsdown/exe` (executables) and `@tsdown/css` (CSS bundling) extensions.
+
+Standalone `@tsdown/exe` and `@tsdown/css` hard-peer-depend on `tsdown` and import
+`tsdown/internal`. Because Vite+ bundles tsdown internally rather than exposing a
+resolvable top-level `tsdown` package, installing them at the project level fails
+to resolve `tsdown/internal` (`Failed to import module "@tsdown/exe"`). See
+[issue #1586](https://github.com/voidzero-dev/vite-plus/issues/1586).
+
+To fix this, both extensions are bundled into core instead of left as peers:
+
+- `packages/core/build.ts` (`bundleTsdown`) builds them as stable named entries
+  `dist/tsdown/tsdown-exe.js` and `dist/tsdown/tsdown-css.js`, so `tsdown/internal`
+  resolves against the bundled tsdown at build time.
+- `wireBundledTsdownExtensions` rewrites the bundled tsdown call sites to load the
+  local chunks (`importWithError("@tsdown/exe")` → `import("./tsdown-exe.js")`,
+  `pkgExists("@tsdown/css")` → `true`, `import("@tsdown/css")` → `import("./tsdown-css.js")`).
+- `mergePackageJson` drops `@tsdown/exe`/`@tsdown/css` from the published
+  `peerDependencies`; their types are inlined into `dist/tsdown/index-types.d.ts`.
+
+`lightningcss` (which `@tsdown/css` uses for CSS transforms) is a native module and
+cannot be bundled. It is an **optional `peerDependency`**: the bundled CSS code
+loads it through an injected `__vpImportLightningcss()` helper that raises an
+actionable error when it is missing:
+
+```
+Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
+```
+
 ## `--exe` Feature (Experimental)
 
 The `--exe` flag bundles the output as a Node.js Single Executable Application (SEA).
@@ -263,13 +297,14 @@ These are distinct commands:
 
 ### 3. tsdown Bundled Inside Core
 
-**Decision**: tsdown is bundled inside `@voidzero-dev/vite-plus-core/pack` rather than used as a direct dependency.
+**Decision**: tsdown is bundled inside `@voidzero-dev/vite-plus-core/pack` rather than used as a direct dependency. Its `@tsdown/exe` and `@tsdown/css` extensions are bundled the same way (see [tsdown Extensions](#bundled-tsdown-extensions)).
 
 **Rationale**:
 
 - Ensures consistent tsdown version across all vite-plus users
 - Avoids version conflicts in monorepos
 - The core build process bundles JS, CJS deps, and types together
+- The extensions peer-depend on `tsdown`/`tsdown/internal`, which Vite+ does not expose as a top-level package, so bundling them is the only way they resolve (issue #1586). Only `lightningcss` (native) stays external as an optional peer.
 
 ### 4. Category C Delegation
 
@@ -342,11 +377,29 @@ Options:
 
 Tests `vp pack -h` (help output includes all options including `--exe`) and `vp run pack` (build and cache hit).
 
-### Local CLI Test: `command-pack-exe`
+### Local CLI Test: `command-pack-css`
+
+**Location**: `packages/cli/snap-tests/command-pack-css/`
+
+Tests `vp pack src/index.ts --minify` on a CSS entry: the bundled `@tsdown/css` plus `lightningcss` transform the CSS (e.g. `#ff0000` → `red`), proving CSS bundling works without installing `@tsdown/css` (issue #1586).
+
+### Local CLI Test: `command-pack-tsdown-extensions`
+
+**Location**: `packages/cli/snap-tests/command-pack-tsdown-extensions/`
+
+Loads the bundled `dist/tsdown/tsdown-exe.js` and `dist/tsdown/tsdown-css.js` chunks to prove they resolve `tsdown/internal` against the bundled tsdown without a top-level `tsdown` package. This is Node-version independent (it does not run the SEA build), so it catches the import-resolution regression on every CI Node version.
+
+### Global CLI Test: `command-pack-exe`
+
+**Location**: `packages/cli/snap-tests-global/command-pack-exe/`
+
+Pins Node.js 25.7.0 (`engines.node`) and builds a real SEA executable end-to-end (`vp pack --exe`, then runs `./build/index`), exercising the bundled `@tsdown/exe`.
+
+### Global CLI Test: `command-pack-exe-error`
 
-**Location**: `packages/cli/snap-tests/command-pack-exe/`
+**Location**: `packages/cli/snap-tests-global/command-pack-exe-error/`
 
-Tests `vp pack src/index.ts --exe` error behavior when Node.js version is below 25.7.0.
+Tests `vp pack src/index.ts --exe` error behavior when the active Node.js version is below 25.7.0.
 
 ## Backward Compatibility
 
@@ -355,6 +408,7 @@ This RFC documents an existing command with no breaking changes:
 - All existing `vp pack` options continue to work
 - The new `--exe` flag is purely additive
 - Config format in `vite.config.ts` is unchanged
+- Bundling `@tsdown/exe`/`@tsdown/css` is a strict improvement: projects that previously installed them keep working and no longer need to. CSS bundling now only requires the optional `lightningcss` peer (`vp add -D lightningcss`), which is loaded lazily with an actionable error when missing.
 
 ## Exe Advanced Configuration
 
@@ -382,7 +436,7 @@ export default {
 
 ### Cross-Platform Executable Building
 
-Cross-platform builds are supported via the `@tsdown/exe` package (optional peer dependency). The `targets` option accepts an array of `{ platform, arch, nodeVersion }` objects to build executables for different platforms from a single host.
+Cross-platform builds are powered by `@tsdown/exe`, which is bundled into core (no separate install needed; see [tsdown Extensions](#bundled-tsdown-extensions)). The `targets` option accepts an array of `{ platform, arch, nodeVersion }` objects to build executables for different platforms from a single host.
 
 ## Conclusion
 

From 67b133c10c8632eb75c08e61b65c31dc4bb513a7 Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 14:21:04 +0800
Subject: [PATCH 2/8] test(pack): cover the missing lightningcss optional peer
 error

Add the command-pack-css-missing-lightningcss snap test: a resolve hook
makes lightningcss unresolvable (the dev/CI monorepo always has it), so
vp pack surfaces the actionable install hint. Locks in that the error
tells users how to fix it.
---
 .../block-lightningcss.mjs                            | 11 +++++++++++
 .../package.json                                      |  5 +++++
 .../register-block.mjs                                |  5 +++++
 .../command-pack-css-missing-lightningcss/snap.txt    |  9 +++++++++
 .../src/index.ts                                      |  3 +++
 .../src/style.css                                     |  3 +++
 .../command-pack-css-missing-lightningcss/steps.json  |  6 ++++++
 rfcs/pack-command.md                                  | 10 ++++++++++
 8 files changed, 52 insertions(+)
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
 create mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json

diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
new file mode 100644
index 0000000000..b92f59cc58
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
@@ -0,0 +1,11 @@
+// Simulate `lightningcss` not being installed: the dev/CI monorepo always has it
+// resolvable from core (it is a transitive dependency), so a resolve hook is the
+// deterministic way to exercise the missing optional-peer path. See issue #1586.
+export async function resolve(specifier, context, nextResolve) {
+  if (specifier === 'lightningcss') {
+    const error = new Error("Cannot find package 'lightningcss'");
+    error.code = 'ERR_MODULE_NOT_FOUND';
+    throw error;
+  }
+  return nextResolve(specifier, context);
+}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
new file mode 100644
index 0000000000..642a49fdbc
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
@@ -0,0 +1,5 @@
+{
+  "name": "command-pack-css-missing-lightningcss",
+  "version": "1.0.0",
+  "type": "module"
+}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
new file mode 100644
index 0000000000..fa004d4181
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
@@ -0,0 +1,5 @@
+import { register } from 'node:module';
+
+// Loaded via `NODE_OPTIONS=--import=./register-block.mjs` so the resolve hook
+// applies to the `vp pack` process (and its managed-Node child).
+register('./block-lightningcss.mjs', import.meta.url);
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
new file mode 100644
index 0000000000..8a6f395405
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
@@ -0,0 +1,9 @@
+[1]> NODE_OPTIONS=--import=./register-block.mjs vp pack src/index.ts --minify # missing optional lightningcss peer prints an actionable install hint (issue #1586)
+ℹ entry: src/index.ts
+ℹ Build start
+error: Build failed with 1 error:
+
+[plugin @tsdown/css] <cwd>/src/style.css
+Error: Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
+Caused by:
+  Error: Cannot find package 'lightningcss'
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
new file mode 100644
index 0000000000..add68f6159
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
@@ -0,0 +1,3 @@
+import './style.css';
+
+export const hello = 'world';
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
new file mode 100644
index 0000000000..97ff765eff
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
@@ -0,0 +1,3 @@
+.foo {
+  color: #ff0000;
+}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json
new file mode 100644
index 0000000000..7a9df9d520
--- /dev/null
+++ b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json
@@ -0,0 +1,6 @@
+{
+  "ignoredPlatforms": ["win32"],
+  "commands": [
+    "NODE_OPTIONS=--import=./register-block.mjs vp pack src/index.ts --minify # missing optional lightningcss peer prints an actionable install hint (issue #1586)"
+  ]
+}
diff --git a/rfcs/pack-command.md b/rfcs/pack-command.md
index 4693aeac7c..e6ff983390 100644
--- a/rfcs/pack-command.md
+++ b/rfcs/pack-command.md
@@ -389,6 +389,16 @@ Tests `vp pack src/index.ts --minify` on a CSS entry: the bundled `@tsdown/css`
 
 Loads the bundled `dist/tsdown/tsdown-exe.js` and `dist/tsdown/tsdown-css.js` chunks to prove they resolve `tsdown/internal` against the bundled tsdown without a top-level `tsdown` package. This is Node-version independent (it does not run the SEA build), so it catches the import-resolution regression on every CI Node version.
 
+### Local CLI Test: `command-pack-css-missing-lightningcss`
+
+**Location**: `packages/cli/snap-tests/command-pack-css-missing-lightningcss/`
+
+Runs `vp pack --minify` with a resolve hook (`NODE_OPTIONS=--import`) that makes `lightningcss` unresolvable, simulating the uninstalled optional peer (the dev/CI monorepo always has it). Asserts the actionable error tells the user how to fix it:
+
+```
+Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
+```
+
 ### Global CLI Test: `command-pack-exe`
 
 **Location**: `packages/cli/snap-tests-global/command-pack-exe/`

From 5862b1343e1973881e56fe1d95ba3a4ec68e0fcb Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 14:27:17 +0800
Subject: [PATCH 3/8] ci(upgrade-deps): keep @tsdown/css and @tsdown/exe in
 lockstep with tsdown

They are bundled into core and exact-peer-depend on the same tsdown
version, so the catalog entries must track tsdown on every upgrade run.
---
 .github/scripts/upgrade-deps.ts | 15 +++++++++++++++
 1 file changed, 15 insertions(+)

diff --git a/.github/scripts/upgrade-deps.ts b/.github/scripts/upgrade-deps.ts
index 301771390b..dbbe25a20e 100644
--- a/.github/scripts/upgrade-deps.ts
+++ b/.github/scripts/upgrade-deps.ts
@@ -212,6 +212,21 @@ async function updatePnpmWorkspace(versions: PnpmWorkspaceVersions): Promise<voi
       replacement: `tsdown: ^${versions.tsdown}`,
       newVersion: versions.tsdown,
     },
+    // `@tsdown/css` and `@tsdown/exe` are bundled into core and published in
+    // lockstep with tsdown (they exact-peer-depend on the same tsdown version),
+    // so pin both catalog entries to the tsdown version to avoid drift.
+    {
+      name: '@tsdown/css',
+      pattern: /'@tsdown\/css': \^([\d.]+(?:-[\w.]+)?)/,
+      replacement: `'@tsdown/css': ^${versions.tsdown}`,
+      newVersion: versions.tsdown,
+    },
+    {
+      name: '@tsdown/exe',
+      pattern: /'@tsdown\/exe': \^([\d.]+(?:-[\w.]+)?)/,
+      replacement: `'@tsdown/exe': ^${versions.tsdown}`,
+      newVersion: versions.tsdown,
+    },
     {
       name: '@oxc-node/cli',
       pattern: /'@oxc-node\/cli': \^([\d.]+(?:-[\w.]+)?)/,

From 98021f5c59d6ecb8608a8ab4ef005663c4c2b137 Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 15:19:35 +0800
Subject: [PATCH 4/8] refactor(pack): ship lightningcss as a core dependency,
 not an optional peer

lightningcss is already a core dependency (Vite's lightningcss transformer
uses it), so the bundled @tsdown/css can use it directly and CSS bundling
works with no extra install. Revert the optional-peer + loader churn: keep
lightningcss in dependencies (via catalog) and drop the
__vpImportLightningcss helper and the missing-lightningcss snap test.
---
 docs/guide/pack.md                            | 10 +--
 .../block-lightningcss.mjs                    | 11 ---
 .../package.json                              |  5 --
 .../register-block.mjs                        |  5 --
 .../snap.txt                                  |  9 ---
 .../src/index.ts                              |  3 -
 .../src/style.css                             |  3 -
 .../steps.json                                |  6 --
 packages/core/build.ts                        | 70 ++++---------------
 packages/core/package.json                    |  6 +-
 pnpm-lock.yaml                                |  9 ++-
 pnpm-workspace.yaml                           |  2 +
 rfcs/pack-command.md                          | 20 +-----
 13 files changed, 28 insertions(+), 131 deletions(-)
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
 delete mode 100644 packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json

diff --git a/docs/guide/pack.md b/docs/guide/pack.md
index 18c70cf6ab..338a4b0e32 100644
--- a/docs/guide/pack.md
+++ b/docs/guide/pack.md
@@ -66,12 +66,4 @@ See the official [tsdown executable docs](https://tsdown.dev/options/exe#executa
 
 ## CSS Bundling
 
-`vp pack` can transform and bundle CSS (including CSS Modules and Lightning CSS optimizations) for your entry points. This support is bundled into Vite+, so you do not need to install `@tsdown/css`.
-
-CSS transforms are powered by [Lightning CSS](https://lightningcss.dev/), which ships as a native module and is an optional peer dependency. Install it when you bundle CSS:
-
-```bash
-vp add -D lightningcss
-```
-
-If it is missing, `vp pack` prints an actionable error telling you to install it.
+`vp pack` can transform and bundle CSS (including CSS Modules and [Lightning CSS](https://lightningcss.dev/) optimizations) for your entry points. This support is bundled into Vite+, so you do not need to install `@tsdown/css` or `lightningcss` separately, it works out of the box.
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
deleted file mode 100644
index b92f59cc58..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/block-lightningcss.mjs
+++ /dev/null
@@ -1,11 +0,0 @@
-// Simulate `lightningcss` not being installed: the dev/CI monorepo always has it
-// resolvable from core (it is a transitive dependency), so a resolve hook is the
-// deterministic way to exercise the missing optional-peer path. See issue #1586.
-export async function resolve(specifier, context, nextResolve) {
-  if (specifier === 'lightningcss') {
-    const error = new Error("Cannot find package 'lightningcss'");
-    error.code = 'ERR_MODULE_NOT_FOUND';
-    throw error;
-  }
-  return nextResolve(specifier, context);
-}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
deleted file mode 100644
index 642a49fdbc..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/package.json
+++ /dev/null
@@ -1,5 +0,0 @@
-{
-  "name": "command-pack-css-missing-lightningcss",
-  "version": "1.0.0",
-  "type": "module"
-}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
deleted file mode 100644
index fa004d4181..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/register-block.mjs
+++ /dev/null
@@ -1,5 +0,0 @@
-import { register } from 'node:module';
-
-// Loaded via `NODE_OPTIONS=--import=./register-block.mjs` so the resolve hook
-// applies to the `vp pack` process (and its managed-Node child).
-register('./block-lightningcss.mjs', import.meta.url);
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
deleted file mode 100644
index 8a6f395405..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/snap.txt
+++ /dev/null
@@ -1,9 +0,0 @@
-[1]> NODE_OPTIONS=--import=./register-block.mjs vp pack src/index.ts --minify # missing optional lightningcss peer prints an actionable install hint (issue #1586)
-ℹ entry: src/index.ts
-ℹ Build start
-error: Build failed with 1 error:
-
-[plugin @tsdown/css] <cwd>/src/style.css
-Error: Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
-Caused by:
-  Error: Cannot find package 'lightningcss'
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
deleted file mode 100644
index add68f6159..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/index.ts
+++ /dev/null
@@ -1,3 +0,0 @@
-import './style.css';
-
-export const hello = 'world';
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
deleted file mode 100644
index 97ff765eff..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/src/style.css
+++ /dev/null
@@ -1,3 +0,0 @@
-.foo {
-  color: #ff0000;
-}
diff --git a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json b/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json
deleted file mode 100644
index 7a9df9d520..0000000000
--- a/packages/cli/snap-tests/command-pack-css-missing-lightningcss/steps.json
+++ /dev/null
@@ -1,6 +0,0 @@
-{
-  "ignoredPlatforms": ["win32"],
-  "commands": [
-    "NODE_OPTIONS=--import=./register-block.mjs vp pack src/index.ts --minify # missing optional lightningcss peer prints an actionable install hint (issue #1586)"
-  ]
-}
diff --git a/packages/core/build.ts b/packages/core/build.ts
index cd012a4106..5950e8cf59 100644
--- a/packages/core/build.ts
+++ b/packages/core/build.ts
@@ -394,8 +394,8 @@ async function bundleTsdown() {
 
   // Everything else in tsdown's peer dependencies stays external. `lightningcss`
   // (a native module) and `postcss` also stay external: `@tsdown/css` pulls them
-  // in, and they cannot be bundled. `lightningcss` becomes an optional peer with
-  // a friendly loader injected by `wireBundledTsdownExtensions()`.
+  // in and they cannot be bundled. Both are core `dependencies`, so they resolve
+  // at runtime and CSS bundling works without users installing anything.
   const tsdownExternal = [
     ...Object.keys(pkgJson.peerDependencies).filter((name) => !bundledTsdownPackages.has(name)),
     'lightningcss',
@@ -585,8 +585,7 @@ async function brandTsdown() {
 
 // Wire the bundled `@tsdown/exe` and `@tsdown/css` extensions into the bundled
 // tsdown so they load from the local chunks instead of resolving external
-// top-level packages, and make `lightningcss` an optional peer with a friendly
-// loader. See https://github.com/voidzero-dev/vite-plus/issues/1586
+// top-level packages. See https://github.com/voidzero-dev/vite-plus/issues/1586
 async function wireBundledTsdownExtensions() {
   const tsdownDistDir = join(projectDir, 'dist/tsdown');
   const buildFiles = await glob(toPosixPath(join(tsdownDistDir, 'build-*.js')), { absolute: true });
@@ -594,11 +593,13 @@ async function wireBundledTsdownExtensions() {
     throw new Error('wireBundledTsdownExtensions: no build chunk found in dist/tsdown/');
   }
 
-  // 1) Route `@tsdown/exe` and `@tsdown/css` to the bundled entries.
-  //    - `importWithError("@tsdown/exe")` dynamically imports a runtime string,
-  //      which rolldown cannot follow, so rewrite the call site to the chunk.
-  //    - `pkgExists("@tsdown/css")` resolves the top-level package at runtime;
-  //      since it is bundled now, force it on and point the import at the chunk.
+  // Route `@tsdown/exe` and `@tsdown/css` to the bundled entries.
+  //   - `importWithError("@tsdown/exe")` dynamically imports a runtime string,
+  //     which rolldown cannot follow, so rewrite the call site to the chunk.
+  //   - `pkgExists("@tsdown/css")` resolves the top-level package at runtime;
+  //     since it is bundled now, force it on and point the import at the chunk.
+  // `@tsdown/css` still imports `lightningcss` (a native module that cannot be
+  // bundled), which resolves to core's own `lightningcss` dependency.
   let exeWired = false;
   let cssWired = false;
   for (const buildFile of buildFiles) {
@@ -628,37 +629,6 @@ async function wireBundledTsdownExtensions() {
   if (!cssWired) {
     throw new Error('wireBundledTsdownExtensions: `pkgExists("@tsdown/css")` not found');
   }
-
-  // 2) `lightningcss` is a native module and an optional peer. Wrap its dynamic
-  //    import so a missing install produces an actionable error instead of a raw
-  //    `Cannot find package 'lightningcss'`.
-  const helper =
-    'async function __vpImportLightningcss() {\n' +
-    '  try {\n' +
-    '    return await import("lightningcss");\n' +
-    '  } catch (cause) {\n' +
-    '    throw new Error(' +
-    '"Cannot find package \\"lightningcss\\". CSS bundling with `vp pack` requires it. ' +
-    'Install it with `vp add -D lightningcss`.", { cause });\n' +
-    '  }\n' +
-    '}\n';
-  const allChunks = await glob(toPosixPath(join(tsdownDistDir, '*.js')), { absolute: true });
-  let lightningcssWired = false;
-  for (const chunk of allChunks) {
-    let content = await readFile(chunk, 'utf-8');
-    if (!content.includes('import("lightningcss")')) {
-      continue;
-    }
-    // Rewrite the call sites first, then prepend the helper (whose own
-    // `import("lightningcss")` must not be rewritten).
-    content = content.replaceAll('import("lightningcss")', '__vpImportLightningcss()');
-    content = helper + content;
-    await writeFile(chunk, content);
-    lightningcssWired = true;
-  }
-  if (!lightningcssWired) {
-    throw new Error('wireBundledTsdownExtensions: `import("lightningcss")` not found');
-  }
 }
 
 // Actually do nothing now, we will polish it in the future when `vitepress` is ready
@@ -755,14 +725,6 @@ async function mergePackageJson() {
   const vitePkg = JSON.parse(await readFile(vitePkgPath, 'utf-8'));
   const destPkg = JSON.parse(await readFile(destPkgPath, 'utf-8'));
 
-  // Track the bundled `@tsdown/css` lightningcss dependency so the optional peer
-  // range stays in lockstep with what the bundled CSS code expects.
-  const require = createRequire(import.meta.url);
-  const tsdownCssPkg = JSON.parse(
-    await readFile(require.resolve('@tsdown/css/package.json'), 'utf-8'),
-  );
-  const lightningcssPeerRange: string = tsdownCssPkg.dependencies?.lightningcss ?? '^1.30.2';
-
   // Merge peerDependencies from tsdown and vite
   destPkg.peerDependencies = {
     ...tsdownPkg.peerDependencies,
@@ -775,17 +737,15 @@ async function mergePackageJson() {
     ...vitePkg.peerDependenciesMeta,
   };
 
-  // `@tsdown/exe` and `@tsdown/css` are bundled into core (see bundleTsdown),
-  // so they must not be advertised as peers anymore. `lightningcss` is a native
-  // module pulled in by the bundled `@tsdown/css` (and Vite's lightningcss
-  // transformer); keep it external as an optional peer so users only install it
-  // when they actually bundle CSS.
+  // `@tsdown/exe` and `@tsdown/css` are bundled into core (see bundleTsdown), so
+  // they must not be advertised as peers anymore. `lightningcss` (which the
+  // bundled `@tsdown/css` and Vite's lightningcss transformer use) stays a core
+  // `dependency`, kept in lockstep with `@tsdown/css` by the upgrade-deps script,
+  // so CSS bundling works without any extra install.
   for (const bundled of ['@tsdown/exe', '@tsdown/css']) {
     delete destPkg.peerDependencies[bundled];
     delete destPkg.peerDependenciesMeta[bundled];
   }
-  destPkg.peerDependencies['lightningcss'] = lightningcssPeerRange;
-  destPkg.peerDependenciesMeta['lightningcss'] = { optional: true };
 
   destPkg.bundledVersions = {
     ...destPkg.bundledVersions,
diff --git a/packages/core/package.json b/packages/core/package.json
index eaa797872b..4f1356f767 100644
--- a/packages/core/package.json
+++ b/packages/core/package.json
@@ -102,6 +102,7 @@
   "dependencies": {
     "@oxc-project/runtime": "catalog:",
     "@oxc-project/types": "catalog:",
+    "lightningcss": "catalog:",
     "postcss": "^8.5.6"
   },
   "devDependencies": {
@@ -116,7 +117,6 @@
     "@vitejs/devtools": "^0.3.3",
     "es-module-lexer": "^1.7.0",
     "hookable": "^6.0.1",
-    "lightningcss": "^1.32.0",
     "magic-string": "^0.30.21",
     "oxc-parser": "catalog:",
     "oxfmt": "catalog:",
@@ -140,7 +140,6 @@
     "esbuild": "^0.27.0 || ^0.28.0",
     "jiti": ">=1.21.0",
     "less": "^4.0.0",
-    "lightningcss": "^1.32.0",
     "publint": "^0.3.8",
     "sass": "^1.70.0",
     "sass-embedded": "^1.70.0",
@@ -204,9 +203,6 @@
     },
     "yaml": {
       "optional": true
-    },
-    "lightningcss": {
-      "optional": true
     }
   },
   "optionalDependencies": {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index 97246307a8..86b4221282 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -183,6 +183,9 @@ catalogs:
     jsonc-parser:
       specifier: ^3.3.1
       version: 3.3.1
+    lightningcss:
+      specifier: ^1.32.0
+      version: 1.32.0
     lint-staged:
       specifier: ^16.2.6
       version: 16.4.0
@@ -525,6 +528,9 @@ importers:
       less:
         specifier: ^4.0.0
         version: 4.4.2
+      lightningcss:
+        specifier: 'catalog:'
+        version: 1.32.0
       postcss:
         specifier: ^8.5.6
         version: 8.5.15
@@ -595,9 +601,6 @@ importers:
       hookable:
         specifier: ^6.0.1
         version: 6.1.1
-      lightningcss:
-        specifier: ^1.32.0
-        version: 1.32.0
       magic-string:
         specifier: ^0.30.21
         version: 0.30.21
diff --git a/pnpm-workspace.yaml b/pnpm-workspace.yaml
index 7fafd253ba..b962b36f57 100644
--- a/pnpm-workspace.yaml
+++ b/pnpm-workspace.yaml
@@ -83,6 +83,8 @@ catalog:
   glob: ^13.0.0
   husky: ^9.1.7
   jsonc-parser: ^3.3.1
+  # Kept in lockstep with the bundled @tsdown/css by .github/scripts/upgrade-deps.ts
+  lightningcss: ^1.32.0
   lint-staged: ^16.2.6
   lodash-es: ^4.17.21
   micromatch: ^4.0.9
diff --git a/rfcs/pack-command.md b/rfcs/pack-command.md
index e6ff983390..8429224a13 100644
--- a/rfcs/pack-command.md
+++ b/rfcs/pack-command.md
@@ -227,13 +227,9 @@ To fix this, both extensions are bundled into core instead of left as peers:
   `peerDependencies`; their types are inlined into `dist/tsdown/index-types.d.ts`.
 
 `lightningcss` (which `@tsdown/css` uses for CSS transforms) is a native module and
-cannot be bundled. It is an **optional `peerDependency`**: the bundled CSS code
-loads it through an injected `__vpImportLightningcss()` helper that raises an
-actionable error when it is missing:
-
-```
-Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
-```
+cannot be bundled, so it stays external. It is already a core `dependency` (Vite's
+lightningcss transformer uses it too), so the bundled `@tsdown/css` resolves it
+automatically and CSS bundling works without any extra install.
 
 ## `--exe` Feature (Experimental)
 
@@ -389,16 +385,6 @@ Tests `vp pack src/index.ts --minify` on a CSS entry: the bundled `@tsdown/css`
 
 Loads the bundled `dist/tsdown/tsdown-exe.js` and `dist/tsdown/tsdown-css.js` chunks to prove they resolve `tsdown/internal` against the bundled tsdown without a top-level `tsdown` package. This is Node-version independent (it does not run the SEA build), so it catches the import-resolution regression on every CI Node version.
 
-### Local CLI Test: `command-pack-css-missing-lightningcss`
-
-**Location**: `packages/cli/snap-tests/command-pack-css-missing-lightningcss/`
-
-Runs `vp pack --minify` with a resolve hook (`NODE_OPTIONS=--import`) that makes `lightningcss` unresolvable, simulating the uninstalled optional peer (the dev/CI monorepo always has it). Asserts the actionable error tells the user how to fix it:
-
-```
-Cannot find package "lightningcss". CSS bundling with `vp pack` requires it. Install it with `vp add -D lightningcss`.
-```
-
 ### Global CLI Test: `command-pack-exe`
 
 **Location**: `packages/cli/snap-tests-global/command-pack-exe/`

From e107015598fa608d9127c8440bb7dd0437e0bb5f Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 15:19:47 +0800
Subject: [PATCH 5/8] ci(upgrade-deps): sync lightningcss with @tsdown/css and
 ignore the extensions in Renovate

lightningcss is a core dependency consumed by the bundled @tsdown/css, so
upgrade-deps now mirrors @tsdown/css's lightningcss range into the catalog
when bumping tsdown. Also ignore @tsdown/css, @tsdown/exe and lightningcss
in Renovate so they stay in lockstep with tsdown instead of drifting.
---
 .github/renovate.json           |  3 +++
 .github/scripts/upgrade-deps.ts | 34 +++++++++++++++++++++++++++++++++
 2 files changed, 37 insertions(+)

diff --git a/.github/renovate.json b/.github/renovate.json
index defc88aa94..afdda01716 100644
--- a/.github/renovate.json
+++ b/.github/renovate.json
@@ -21,7 +21,10 @@
         "/^oxc-.*/",
         "@oxc-node/*",
         "@oxc-project/*",
+        "@tsdown/css",
+        "@tsdown/exe",
         "@vitejs/devtools",
+        "lightningcss",
         "oxfmt",
         "oxlint",
         "oxlint-tsgolint",
diff --git a/.github/scripts/upgrade-deps.ts b/.github/scripts/upgrade-deps.ts
index dbbe25a20e..9de95e42cd 100644
--- a/.github/scripts/upgrade-deps.ts
+++ b/.github/scripts/upgrade-deps.ts
@@ -42,6 +42,7 @@ type UpstreamVersions = {
 type PnpmWorkspaceVersions = {
   vitest: string;
   tsdown: string;
+  lightningcss: string;
   oxcNodeCli: string;
   oxcNodeCore: string;
   oxfmt: string;
@@ -145,6 +146,25 @@ async function getLatestNpmVersion(packageName: string): Promise<string> {
   return data.version;
 }
 
+// Read a dependency range from the latest published version of `packageName`,
+// e.g. the `lightningcss` range that the bundled `@tsdown/css` depends on.
+async function getNpmDependencyRange(packageName: string, dependencyName: string): Promise<string> {
+  const res = await fetch(`https://registry.npmjs.org/${packageName}/latest`);
+  if (!res.ok) {
+    throw new Error(
+      `Failed to fetch npm metadata for ${packageName}: ${res.status} ${res.statusText}`,
+    );
+  }
+  const data = (await res.json()) as { dependencies?: Record<string, string> };
+  const range = data.dependencies?.[dependencyName];
+  if (typeof range !== 'string') {
+    throw new Error(
+      `Invalid npm response for ${packageName}: missing dependencies.${dependencyName}`,
+    );
+  }
+  return range;
+}
+
 // ============ Update .upstream-versions.json ============
 async function updateUpstreamVersions(): Promise<void> {
   const filePath = path.join(ROOT, 'packages/tools/.upstream-versions.json');
@@ -227,6 +247,15 @@ async function updatePnpmWorkspace(versions: PnpmWorkspaceVersions): Promise<voi
       replacement: `'@tsdown/exe': ^${versions.tsdown}`,
       newVersion: versions.tsdown,
     },
+    // `lightningcss` is a core dependency consumed by the bundled `@tsdown/css`.
+    // Track exactly what `@tsdown/css` requires (already an `^x.y.z` range) so a
+    // tsdown upgrade that bumps lightningcss is mirrored here.
+    {
+      name: 'lightningcss',
+      pattern: /\n {2}lightningcss: (\^?[\d.]+(?:-[\w.]+)?)\n/,
+      replacement: `\n  lightningcss: ${versions.lightningcss}\n`,
+      newVersion: versions.lightningcss,
+    },
     {
       name: '@oxc-node/cli',
       pattern: /'@oxc-node\/cli': \^([\d.]+(?:-[\w.]+)?)/,
@@ -531,6 +560,7 @@ console.log('Fetching latest versions…');
 const [
   vitestVersion,
   tsdownVersion,
+  lightningcssVersion,
   devtoolsVersion,
   oxcNodeCliVersion,
   oxcNodeCoreVersion,
@@ -545,6 +575,8 @@ const [
 ] = await Promise.all([
   getLatestNpmVersion('vitest'),
   getLatestNpmVersion('tsdown'),
+  // Mirror exactly what the bundled @tsdown/css depends on.
+  getNpmDependencyRange('@tsdown/css', 'lightningcss'),
   getLatestNpmVersion('@vitejs/devtools'),
   getLatestNpmVersion('@oxc-node/cli'),
   getLatestNpmVersion('@oxc-node/core'),
@@ -560,6 +592,7 @@ const [
 
 console.log(`vitest: ${vitestVersion}`);
 console.log(`tsdown: ${tsdownVersion}`);
+console.log(`lightningcss (from @tsdown/css): ${lightningcssVersion}`);
 console.log(`@vitejs/devtools: ${devtoolsVersion}`);
 console.log(`@oxc-node/cli: ${oxcNodeCliVersion}`);
 console.log(`@oxc-node/core: ${oxcNodeCoreVersion}`);
@@ -576,6 +609,7 @@ await updateUpstreamVersions();
 await updatePnpmWorkspace({
   vitest: vitestVersion,
   tsdown: tsdownVersion,
+  lightningcss: lightningcssVersion,
   oxcNodeCli: oxcNodeCliVersion,
   oxcNodeCore: oxcNodeCoreVersion,
   oxfmt: oxfmtVersion,

From 9d18d6649b296677aca0422c327f4d8a9b2b4a1c Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 20:35:43 +0800
Subject: [PATCH 6/8] fix(pack): harden tsdown extension wiring and
 lightningcss version sync

- wireBundledTsdownExtensions: scan every emitted chunk (not just
  build-*.js) and assert the bundled ./tsdown-css.js is referenced, so a
  rolldown chunking change can't silently ship an unrewritten import.
- upgrade-deps: match any lightningcss range value so a non-caret range
  from @tsdown/css can't poison the next run's pattern.
- rfc: lightningcss is a core dependency, not an optional peer.
---
 .github/scripts/upgrade-deps.ts |  4 +++-
 packages/core/build.ts          | 24 ++++++++++++++++++------
 rfcs/pack-command.md            |  4 ++--
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/.github/scripts/upgrade-deps.ts b/.github/scripts/upgrade-deps.ts
index 9de95e42cd..92863a5133 100644
--- a/.github/scripts/upgrade-deps.ts
+++ b/.github/scripts/upgrade-deps.ts
@@ -252,7 +252,9 @@ async function updatePnpmWorkspace(versions: PnpmWorkspaceVersions): Promise<voi
     // tsdown upgrade that bumps lightningcss is mirrored here.
     {
       name: 'lightningcss',
-      pattern: /\n {2}lightningcss: (\^?[\d.]+(?:-[\w.]+)?)\n/,
+      // Match any range value (not just `^x.y.z`) so the pattern can re-match
+      // whatever `@tsdown/css` declares (`~`, `>=`, compound ranges) on the next run.
+      pattern: /\n {2}lightningcss: ([^\n]+)\n/,
       replacement: `\n  lightningcss: ${versions.lightningcss}\n`,
       newVersion: versions.lightningcss,
     },
diff --git a/packages/core/build.ts b/packages/core/build.ts
index 5950e8cf59..b9b0e487b6 100644
--- a/packages/core/build.ts
+++ b/packages/core/build.ts
@@ -588,9 +588,11 @@ async function brandTsdown() {
 // top-level packages. See https://github.com/voidzero-dev/vite-plus/issues/1586
 async function wireBundledTsdownExtensions() {
   const tsdownDistDir = join(projectDir, 'dist/tsdown');
-  const buildFiles = await glob(toPosixPath(join(tsdownDistDir, 'build-*.js')), { absolute: true });
-  if (buildFiles.length === 0) {
-    throw new Error('wireBundledTsdownExtensions: no build chunk found in dist/tsdown/');
+  // Scan every emitted chunk, not just `build-*.js`: which chunk rolldown hoists
+  // these call sites into depends on its chunking heuristics, so don't pin to one.
+  const chunkFiles = await glob(toPosixPath(join(tsdownDistDir, '*.js')), { absolute: true });
+  if (chunkFiles.length === 0) {
+    throw new Error('wireBundledTsdownExtensions: no chunk found in dist/tsdown/');
   }
 
   // Route `@tsdown/exe` and `@tsdown/css` to the bundled entries.
@@ -602,8 +604,12 @@ async function wireBundledTsdownExtensions() {
   // bundled), which resolves to core's own `lightningcss` dependency.
   let exeWired = false;
   let cssWired = false;
-  for (const buildFile of buildFiles) {
-    let content = await readFile(buildFile, 'utf-8');
+  // The `import("@tsdown/css")` call site may already be deduped to the bundled
+  // entry by rolldown; track whether the bundled load ends up referenced either
+  // way so a silent miss (no rewrite and no dedup) fails the build.
+  let cssLoadWired = false;
+  for (const chunkFile of chunkFiles) {
+    let content = await readFile(chunkFile, 'utf-8');
     let changed = false;
     if (content.includes('importWithError("@tsdown/exe")')) {
       content = content.replaceAll('importWithError("@tsdown/exe")', 'import("./tsdown-exe.js")');
@@ -619,8 +625,11 @@ async function wireBundledTsdownExtensions() {
       content = content.replaceAll('import("@tsdown/css")', 'import("./tsdown-css.js")');
       changed = true;
     }
+    if (content.includes('import("./tsdown-css.js")')) {
+      cssLoadWired = true;
+    }
     if (changed) {
-      await writeFile(buildFile, content);
+      await writeFile(chunkFile, content);
     }
   }
   if (!exeWired) {
@@ -629,6 +638,9 @@ async function wireBundledTsdownExtensions() {
   if (!cssWired) {
     throw new Error('wireBundledTsdownExtensions: `pkgExists("@tsdown/css")` not found');
   }
+  if (!cssLoadWired) {
+    throw new Error('wireBundledTsdownExtensions: bundled `./tsdown-css.js` is never imported');
+  }
 }
 
 // Actually do nothing now, we will polish it in the future when `vitepress` is ready
diff --git a/rfcs/pack-command.md b/rfcs/pack-command.md
index 8429224a13..1974a5cd99 100644
--- a/rfcs/pack-command.md
+++ b/rfcs/pack-command.md
@@ -300,7 +300,7 @@ These are distinct commands:
 - Ensures consistent tsdown version across all vite-plus users
 - Avoids version conflicts in monorepos
 - The core build process bundles JS, CJS deps, and types together
-- The extensions peer-depend on `tsdown`/`tsdown/internal`, which Vite+ does not expose as a top-level package, so bundling them is the only way they resolve (issue #1586). Only `lightningcss` (native) stays external as an optional peer.
+- The extensions peer-depend on `tsdown`/`tsdown/internal`, which Vite+ does not expose as a top-level package, so bundling them is the only way they resolve (issue #1586). Only `lightningcss` (native, cannot be bundled) stays external; it ships as a regular core dependency.
 
 ### 4. Category C Delegation
 
@@ -404,7 +404,7 @@ This RFC documents an existing command with no breaking changes:
 - All existing `vp pack` options continue to work
 - The new `--exe` flag is purely additive
 - Config format in `vite.config.ts` is unchanged
-- Bundling `@tsdown/exe`/`@tsdown/css` is a strict improvement: projects that previously installed them keep working and no longer need to. CSS bundling now only requires the optional `lightningcss` peer (`vp add -D lightningcss`), which is loaded lazily with an actionable error when missing.
+- Bundling `@tsdown/exe`/`@tsdown/css` is a strict improvement: projects that previously installed them keep working and no longer need to. CSS bundling works out of the box, `lightningcss` is a core dependency that ships with the toolchain, so nothing extra needs installing.
 
 ## Exe Advanced Configuration
 

From ec3b9b28dca9b46e4629b13db3cb32d5b8b11484 Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 20:51:50 +0800
Subject: [PATCH 7/8] refactor(upgrade-deps): share npm registry fetch helper

getLatestNpmVersion and getNpmDependencyRange duplicated the same
registry fetch + ok-check + json block; extract fetchNpmLatest so the
registry URL and error wording live in one place.
---
 .github/scripts/upgrade-deps.ts | 19 +++++++++----------
 1 file changed, 9 insertions(+), 10 deletions(-)

diff --git a/.github/scripts/upgrade-deps.ts b/.github/scripts/upgrade-deps.ts
index 92863a5133..3efe521527 100644
--- a/.github/scripts/upgrade-deps.ts
+++ b/.github/scripts/upgrade-deps.ts
@@ -28,6 +28,7 @@ type LatestTagOptions = {
 
 type NpmLatestResponse = {
   version?: unknown;
+  dependencies?: Record<string, string>;
 };
 
 type UpstreamVersions = {
@@ -132,14 +133,18 @@ async function getLatestTag(
 }
 
 // ============ npm Registry ============
-async function getLatestNpmVersion(packageName: string): Promise<string> {
+async function fetchNpmLatest(packageName: string): Promise<NpmLatestResponse> {
   const res = await fetch(`https://registry.npmjs.org/${packageName}/latest`);
   if (!res.ok) {
     throw new Error(
-      `Failed to fetch npm version for ${packageName}: ${res.status} ${res.statusText}`,
+      `Failed to fetch npm metadata for ${packageName}: ${res.status} ${res.statusText}`,
     );
   }
-  const data = (await res.json()) as NpmLatestResponse;
+  return (await res.json()) as NpmLatestResponse;
+}
+
+async function getLatestNpmVersion(packageName: string): Promise<string> {
+  const data = await fetchNpmLatest(packageName);
   if (typeof data.version !== 'string') {
     throw new Error(`Invalid npm response for ${packageName}: missing version field`);
   }
@@ -149,13 +154,7 @@ async function getLatestNpmVersion(packageName: string): Promise<string> {
 // Read a dependency range from the latest published version of `packageName`,
 // e.g. the `lightningcss` range that the bundled `@tsdown/css` depends on.
 async function getNpmDependencyRange(packageName: string, dependencyName: string): Promise<string> {
-  const res = await fetch(`https://registry.npmjs.org/${packageName}/latest`);
-  if (!res.ok) {
-    throw new Error(
-      `Failed to fetch npm metadata for ${packageName}: ${res.status} ${res.statusText}`,
-    );
-  }
-  const data = (await res.json()) as { dependencies?: Record<string, string> };
+  const data = await fetchNpmLatest(packageName);
   const range = data.dependencies?.[dependencyName];
   if (typeof range !== 'string') {
     throw new Error(

From 12560ea3509b77709b7a5ce368b6505117fb1d1e Mon Sep 17 00:00:00 2001
From: MK <fengmk2@gmail.com>
Date: Tue, 23 Jun 2026 20:55:30 +0800
Subject: [PATCH 8/8] docs(pack): suggest `vp env use 26` for the exe SEA build

Node 26 is the version the exe targets default to and clears the 25.7
SEA floor; `vp env use 25` could resolve below it.
---
 docs/guide/pack.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/docs/guide/pack.md b/docs/guide/pack.md
index 338a4b0e32..2bcc6c8da9 100644
--- a/docs/guide/pack.md
+++ b/docs/guide/pack.md
@@ -60,7 +60,7 @@ export default defineConfig({
 
 Executable support is bundled into Vite+, so you do not need to install `@tsdown/exe` separately.
 
-Building executables uses Node's [Single Executable Applications](https://nodejs.org/api/single-executable-applications.html) support and requires Node.js 25.7.0 or later. Switch the active runtime with `vp env use 25` if `vp pack --exe` reports an unsupported version.
+Building executables uses Node's [Single Executable Applications](https://nodejs.org/api/single-executable-applications.html) support and requires Node.js 25.7.0 or later. Switch the active runtime with `vp env use 26` if `vp pack --exe` reports an unsupported version.
 
 See the official [tsdown executable docs](https://tsdown.dev/options/exe#executable) for details about configuring custom file names, embedded assets, and cross-platform targets.