fix(vite)!: replace buffer polyfill with data-uri-to-buffer shim

docs/implementation-docs/2026-03-26-cedarjs-project-overview.md

@@ -142,7 +142,7 @@ cedar build:
 *SSR/RSC: falls back to legacy separate builds; adds route hooks build, route
   manifest, SSR client+server builds.
 
-Vite plugins: cell transform | entry injection | html env | node polyfills |
+Vite plugins: cell transform | entry injection | html env | data-uri-to-buffer shim |
   auto-imports | import-dir | js-as-jsx | merged config | api-babel-transform |
   cedar-routes-auto-loader | cedar-universal-deploy | cedar-wait-for-api-server
   *SSR/RSC: adds RSC transforms

packages/vite/package.json

@@ -82,7 +82,6 @@
     "acorn": "8.16.0",
     "acorn-loose": "8.5.2",
     "ansis": "4.2.0",
-    "buffer": "6.0.3",
     "busboy": "^1.6.0",
     "cookie": "1.1.1",
     "dotenv-defaults": "5.0.2",
@@ -99,7 +98,6 @@
     "rou3": "^0.8.1",
     "vite": "7.3.5",
     "vite-plugin-cjs-interop": "2.4.4",
-    "vite-plugin-node-polyfills": "0.26.0",
     "ws": "8.20.0",
     "yargs-parser": "21.1.1"
   },

packages/vite/src/devFeServer.ts

@@ -278,22 +278,10 @@ async function createServer() {
           'busboy',
           'cookie',
         ],
-        // Without excluding `util` we get "TypeError: util.TextEncoder is not
-        // a constructor" in react-server-dom-webpack.server because it'll try
-        // to use Browserify's `util` instead of Node's. And Browserify's
-        // polyfill is missing TextEncoder+TextDecoder. The reason it's using
-        // the Browserify polyfill is because we have
-        // `vite-plugin-node-polyfills` as a dependency, and that'll add
-        // Browserify's `node-util` to `node_modules`, so when Vite goes to
-        // resolve `import { TextEncoder } from 'util` it'll find the one in
-        // `node_modules` instead of Node's internal version.
-        // We only see this in dev, and not in prod. I'm not entirely sure why
-        // but I have two guesses: 1. When RSC is enabled we don't actually use
-        // `vite-plugin-node-polyfill`, so some kind of tree shaking is
-        // happening, which prevents the issue from occurring. 2. In prod we
-        // only use Node's dependency resolution. Vite is not involved. And
-        // that difference in resolution is what prevents the issue from
-        // occurring.
+        // Ensure `util` resolves to Node's built-in module and not to
+        // Browserify's `node-util` polyfill (which lacks TextEncoder).
+        // The polyfill may be hoisted into node_modules by optional
+        // dependencies like `@cedarjs/storybook`.
         exclude: ['util'],
       },
     },

packages/vite/src/index.ts

@@ -10,9 +10,9 @@ import {
 } from '@cedarjs/testing/web/vitest'
 
 import { cedarCellTransform } from './plugins/vite-plugin-cedar-cell.js'
+import { cedarDataUriShim } from './plugins/vite-plugin-cedar-data-uri-shim.js'
 import { cedarEntryInjectionPlugin } from './plugins/vite-plugin-cedar-entry-injection.js'
 import { cedarHtmlEnvPlugin } from './plugins/vite-plugin-cedar-html-env.js'
-import { cedarNodePolyfills } from './plugins/vite-plugin-cedar-node-polyfills.js'
 import { cedarRemoveDevFatalErrorPage } from './plugins/vite-plugin-cedar-remove-dev-fatal-error-page.js'
 import { cedarRemoveFromBundle } from './plugins/vite-plugin-cedar-remove-from-bundle.js'
 import { cedarRoutesAutoLoaderPlugin } from './plugins/vite-plugin-cedar-routes-auto-loader.js'
@@ -28,7 +28,7 @@ export { cedarCellTransform } from './plugins/vite-plugin-cedar-cell.js'
 export { cedarEntryInjectionPlugin } from './plugins/vite-plugin-cedar-entry-injection.js'
 export { cedarHtmlEnvPlugin } from './plugins/vite-plugin-cedar-html-env.js'
 export { cedarImportDirPlugin } from './plugins/vite-plugin-cedar-import-dir.js'
-export { cedarNodePolyfills } from './plugins/vite-plugin-cedar-node-polyfills.js'
+export { cedarDataUriShim } from './plugins/vite-plugin-cedar-data-uri-shim.js'
 export { cedarRemoveDevFatalErrorPage } from './plugins/vite-plugin-cedar-remove-dev-fatal-error-page.js'
 export { cedarRoutesAutoLoaderPlugin } from './plugins/vite-plugin-cedar-routes-auto-loader.js'
 export { cedarRemoveFromBundle } from './plugins/vite-plugin-cedar-remove-from-bundle.js'
@@ -65,7 +65,7 @@ export function cedar({ mode }: PluginOptions = {}): PluginOption[] {
     mode === 'test' && createAuthImportTransformPlugin(),
     mode === 'test' && autoImportsPlugin(),
     cedarWaitForApiServer(),
-    cedarNodePolyfills(),
+    cedarDataUriShim(),
     cedarHtmlEnvPlugin(),
     cedarEntryInjectionPlugin(),
     cedarMergedConfig(),

packages/vite/src/plugins/vite-plugin-cedar-data-uri-shim.ts

@@ -0,0 +1,61 @@
+import type { Plugin } from 'vite'
+
+import { getConfig } from '@cedarjs/project-config'
+
+function dataUriToBuffer(uri: string) {
+  const match = uri.match(/^data:(.*?)(;(.*?))?(,(.*))$/)
+  if (!match) {
+    throw new Error('Invalid data URI')
+  }
+
+  const mediaType = match[1] || 'text/plain'
+  const params = match[3] || ''
+  const data = match[5]
+
+  const [type] = mediaType.split(';')
+  const typeFull = params ? mediaType + ';' + params : mediaType
+
+  const lowerParams = params.toLowerCase()
+  const isBase64 = lowerParams.includes('base64')
+
+  const charset = lowerParams.startsWith('charset=') ? lowerParams.slice(8) : ''
+
+  const bytes = isBase64
+    ? Uint8Array.from(atob(data), (c) => c.charCodeAt(0))
+    : new TextEncoder().encode(decodeURIComponent(data))
+
+  const decoder = new TextDecoder()
+  bytes.toString = () => decoder.decode(bytes)
+
+  return Object.assign(bytes, { type, typeFull, charset })
+}
+
+export function cedarDataUriShim(): Plugin | undefined {
+  // `stacktracey` pulls in `get-source`, which uses an old version of
+  // `data-uri-to-buffer` that returns a `Buffer`. Since `data-uri-to-buffer`
+  // is only used for inline source map parsing in the dev error page, we
+  // replace it with a tiny shim that returns a `Uint8Array` instead.
+  //
+  // This avoids needing a full Buffer polyfill.
+
+  if (getConfig().experimental?.rsc?.enabled) {
+    return undefined
+  }
+
+  return {
+    name: 'cedar-data-uri-shim',
+    apply: 'serve',
+    resolveId(id) {
+      if (id === 'data-uri-to-buffer') {
+        return '\0cedar-data-uri-to-buffer'
+      }
+      return undefined
+    },
+    load(id) {
+      if (id === '\0cedar-data-uri-to-buffer') {
+        return 'export default ' + dataUriToBuffer.toString()
+      }
+      return undefined
+    },
+  }
+}

yarn.lock

@@ -3772,7 +3772,6 @@ __metadata:
     acorn: "npm:8.16.0"
     acorn-loose: "npm:8.5.2"
     ansis: "npm:4.2.0"
-    buffer: "npm:6.0.3"
     busboy: "npm:^1.6.0"
     concurrently: "npm:9.2.1"
     cookie: "npm:1.1.1"
@@ -3797,7 +3796,6 @@ __metadata:
     typescript: "npm:5.9.3"
     vite: "npm:7.3.5"
     vite-plugin-cjs-interop: "npm:2.4.4"
-    vite-plugin-node-polyfills: "npm:0.26.0"
     vitest: "npm:3.2.6"
     ws: "npm:8.20.0"
     yargs-parser: "npm:21.1.1"
@@ -13721,7 +13719,7 @@ __metadata:
   languageName: node
   linkType: hard
 
-"buffer@npm:6.0.3, buffer@npm:^6.0.3":
+"buffer@npm:^6.0.3":
   version: 6.0.3
   resolution: "buffer@npm:6.0.3"
   dependencies: