diff --git a/packages/boxel-ui/addon/bin/conditional-build.sh b/packages/boxel-ui/addon/bin/conditional-build.sh
deleted file mode 100755
index d56f58bf64b..00000000000
--- a/packages/boxel-ui/addon/bin/conditional-build.sh
+++ /dev/null
@@ -1,29 +0,0 @@
-#! /bin/sh
-
-CURRENT_DIR="$(pwd)"
-SCRIPTS_DIR="$(cd "$(dirname "$0")" && pwd)"
-
-SRC_DIR="${SCRIPTS_DIR}/../src"
-DIST_DIR="${SCRIPTS_DIR}/../dist"
-
-if [ ! -d "$DIST_DIR" ]; then
-  echo "boxel-ui/addon dist dir does not exist. Building in ${SRC_DIR}/.."
-  cd "${SRC_DIR}/.."
-  pnpm run build
-  exit 0
-fi
-if [ "$(uname)" = "Darwin" ]; then
-  mod_time_src=$(find "$SRC_DIR" -type f -exec stat -f %m {} + | sort -nr | head -n1)
-  mod_time_dist=$(find "$DIST_DIR" -type f -exec stat -f %m {} + | sort -nr | head -n1)
-else
-  mod_time_src=$(find "$SRC_DIR" -type f -printf "%T@\n" | sort -nr | head -n1 | cut -d. -f1)
-  mod_time_dist=$(find "$DIST_DIR" -type f -printf "%T@\n" | sort -nr | head -n1 | cut -d. -f1)
-fi
-
-if [ "$mod_time_src" -gt "$mod_time_dist" ]; then
-  echo "boxel-ui/addon dist dir is out of date. Building in ${SRC_DIR}/.."
-  cd "${SRC_DIR}/.."
-  pnpm run build
-else
-  echo "✔️ boxel-ui/addon dist dir is up to date"
-fi
diff --git a/packages/boxel-ui/addon/package.json b/packages/boxel-ui/addon/package.json
index 3138327c8eb..9e71ec09718 100644
--- a/packages/boxel-ui/addon/package.json
+++ b/packages/boxel-ui/addon/package.json
@@ -14,7 +14,6 @@
   },
   "scripts": {
     "build": "concurrently \"pnpm:build:*\" --names \"build:\"",
-    "build:js": "echo 'noop'",
     "build:types": "ember-tsc --declaration --emitDeclarationOnly --noEmit false",
     "lint": "concurrently \"pnpm:lint:*(!fix)\" --names \"lint:\"",
     "lint:fix": "concurrently \"pnpm:lint:*:fix\" --names \"fix:\"",
@@ -26,9 +25,7 @@
     "rebuild:icons": "node bin/rebuild-icons.mjs",
     "rebuild:usage": "node bin/rebuild-usage.mjs",
     "generate:component-specs": "node bin/generate-component-specs.mjs",
-    "prepack": "rollup --config",
     "start": "concurrently \"pnpm:start:*\" --names \"start:\"",
-    "start:js": "rollup --config --watch --no-watch.clearScreen",
     "start:types": "ember-tsc --declaration --emitDeclarationOnly --watch",
     "test": "echo 'A v2 addon does not have tests, run tests in test-app'",
     "test:ember": "ember test"
@@ -79,7 +76,6 @@
     "@cardstack/local-types": "workspace:*",
     "@embroider/addon-dev": "^8.0.0",
     "@embroider/macros": "~1.16.5",
-    "@rollup/plugin-babel": "catalog:",
     "@tsconfig/ember": "3.0.1",
     "@types/dompurify": "catalog:",
     "@types/lodash-es": "catalog:",
@@ -101,8 +97,6 @@
     "glimmer-scoped-css": "catalog:",
     "prettier": "catalog:",
     "prettier-plugin-ember-template-tag": "catalog:",
-    "rollup": "catalog:",
-    "rollup-plugin-copy": "catalog:",
     "svgo": "catalog:",
     "@glint/ember-tsc": "catalog:"
   },
@@ -134,7 +128,6 @@
   "files": [
     "addon-main.cjs",
     "declarations",
-    "dist",
     "public"
   ],
   "typesVersions": {
diff --git a/packages/boxel-ui/addon/rollup.config.mjs b/packages/boxel-ui/addon/rollup.config.mjs
deleted file mode 100644
index 123f6fec0f7..00000000000
--- a/packages/boxel-ui/addon/rollup.config.mjs
+++ /dev/null
@@ -1,91 +0,0 @@
-import { Addon } from '@embroider/addon-dev/rollup';
-import { babel } from '@rollup/plugin-babel';
-import { scopedCSS } from 'glimmer-scoped-css/rollup';
-import copy from 'rollup-plugin-copy';
-
-const addon = new Addon({
-  srcDir: 'src',
-  destDir: 'dist',
-});
-
-export default {
-  // This provides defaults that work well alongside `publicEntrypoints` below.
-  // You can augment this if you need to.
-  output: addon.output(),
-
-  plugins: [
-    scopedCSS('src'),
-
-    // These are the modules that users should be able to import from your
-    // addon. Anything not listed here may get optimized away.
-    addon.publicEntrypoints([
-      'components.js',
-      'helpers.js',
-      'icons.js',
-      'modifiers.js',
-      'usage.js',
-    ]),
-
-    // These are the modules that should get reexported into the traditional
-    // "app" tree. Things in here should also be in publicEntrypoints above, but
-    // not everything in publicEntrypoints necessarily needs to go here.
-    addon.appReexports([]),
-
-    // Follow the V2 Addon rules about dependencies. Your code can import from
-    // `dependencies` and `peerDependencies` as well as standard Ember-provided
-    // package names.
-    addon.dependencies(),
-
-    // Ensure that standalone .hbs files are properly integrated as Javascript.
-    addon.hbs(),
-
-    // Ensure that .gjs files are properly integrated as Javascript
-    addon.gjs(),
-
-    // css is importable for side-effect
-    addon.keepAssets(['**/*.css']),
-
-    // these asset types are imported for their URLs
-    addon.keepAssets(
-      ['**/*.otf', '**/*.png', '**/*.webp', '**/*.woff2'],
-      'default',
-    ),
-
-    // Remove leftover build artifacts when starting a new build.
-    addon.clean({ runOnce: true }),
-
-    // Copy Readme and License into published package
-    copy({
-      targets: [
-        { src: '../README.md', dest: '.' },
-        { src: '../LICENSE.md', dest: '.' },
-        { src: './src/styles/*.{css,woff2,otf}', dest: './dist/styles' },
-        { src: './src/styles/LICENSE.txt', dest: './dist/styles' },
-      ],
-      // this makes it late enough that the `clean()` hook above doesn't remove
-      // our copied files
-      hook: 'generateBundle',
-    }),
-
-    // This babel config should *not* apply presets or compile away ES modules.
-    // It exists only to provide development niceties for you, like automatic
-    // template colocation.
-    //
-    // By default, this will load the actual babel config from the file
-    // babel.config.json.
-    babel({
-      babelHelpers: 'bundled',
-      extensions: ['.js', '.gjs', '.ts', '.gts'],
-    }),
-  ],
-
-  onLog(level, log, handler) {
-    if (log.code === 'UNUSED_EXTERNAL_IMPORT') {
-      // Turn unused external imports from warnings to errors. Warnings
-      // accumulate and just generate noise. And this is an easily-fixable issue
-      // usually caused by failing to declare a type import correctly.
-      level = 'error';
-    }
-    handler(level, log);
-  },
-};
diff --git a/packages/host/package.json b/packages/host/package.json
index 053aa78047e..a02fb34b602 100644
--- a/packages/host/package.json
+++ b/packages/host/package.json
@@ -20,7 +20,6 @@
     "lint:js": "eslint . --report-unused-disable-directives --cache",
     "lint:js:fix": "eslint . --report-unused-disable-directives --fix",
     "lint:types": "ember-tsc --noEmit",
-    "ensure-boxel-ui": "../boxel-ui/addon/bin/conditional-build.sh",
     "start": "node scripts/vite-serve.js",
     "serve:dist": "node scripts/serve-dist.js",
     "test": "concurrently \"pnpm:lint\" \"pnpm:test:*\" --names \"lint,test:\"",
diff --git a/packages/host/scripts/vite-serve.js b/packages/host/scripts/vite-serve.js
index 3949c1b852d..f034decb26a 100644
--- a/packages/host/scripts/vite-serve.js
+++ b/packages/host/scripts/vite-serve.js
@@ -2,41 +2,13 @@
  * Wrapper around `vite` (dev server) for `pnpm start`. Delegates to the
  * shared launcher, which handles BOXEL_ENVIRONMENT / Traefik registration.
  * Mirrors scripts/serve-dist.js, which does the same for `vite preview`.
- *
- * Runs `ensure-boxel-ui` inline (synchronously, via execFileSync) so that
- * the `start` script can be a single `node ...` command rather than
- * `pnpm ensure-boxel-ui && node ...`. With `&&` chaining, pnpm runs the
- * script through `sh -c`, which has no SIGTERM handler — so on Ctrl-C
- * the shell dies via signal even though this Node process exits 0,
- * leaving pnpm to report `Command failed with signal "SIGTERM"` and
- * `[ERR_PNPM_RECURSIVE_RUN_FIRST_FAIL]`. Running ensure-boxel-ui
- * inline keeps Node as pnpm's direct child, so pnpm sees our clean exit.
  */
 
-const { execFileSync } = require('child_process');
-const path = require('path');
-
-// Refuse a second env-mode vite from this worktree BEFORE the boxel-ui
-// conditional-build runs — that step can take many seconds when the
-// addon dist is stale, which would look like a hang to the user instead
-// of a clear error. See env-mode-lock.js for the underlying constraint.
+// Refuse a second env-mode vite from this worktree before we start, so the
+// second start exits with a clear error instead of racing the first. See
+// env-mode-lock.js for the underlying constraint.
 require('./env-mode-lock').refuseIfAnotherSlugLocked();
 
-execFileSync(
-  path.join(
-    __dirname,
-    '..',
-    '..',
-    'boxel-ui',
-    'addon',
-    'bin',
-    'conditional-build.sh',
-  ),
-  {
-    stdio: 'inherit',
-  },
-);
-
 const { startWithTraefik } = require('./vite-with-traefik');
 
 startWithTraefik({
diff --git a/packages/host/scripts/vite-with-traefik.js b/packages/host/scripts/vite-with-traefik.js
index 30115f5e703..28f414f7b1d 100644
--- a/packages/host/scripts/vite-with-traefik.js
+++ b/packages/host/scripts/vite-with-traefik.js
@@ -294,8 +294,8 @@ function startWithTraefik({ subcommand, defaultPort, label, nodeMemory }) {
 
   const slug = getEnvSlug();
   // Belt-and-suspenders: vite-serve.js / serve-dist.js also call this
-  // up-front (before boxel-ui conditional-build) so the second start
-  // exits immediately. Repeat here for direct callers of startWithTraefik.
+  // up-front so the second start exits immediately. Repeat here for
+  // direct callers of startWithTraefik.
   refuseIfAnotherSlugLocked();
 
   ensureTraefik();
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index f7cf7cd2cdd..a9d42b97bec 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -1379,9 +1379,6 @@ importers:
       '@glint/ember-tsc':
         specifier: 'catalog:'
         version: 1.5.0(typescript@5.9.3)
-      '@rollup/plugin-babel':
-        specifier: 'catalog:'
-        version: 6.1.0(@babel/core@7.29.7)(@types/babel__core@7.20.5)(rollup@4.62.0)
       '@tsconfig/ember':
         specifier: 3.0.1
         version: 3.0.1
@@ -1445,12 +1442,6 @@ importers:
       prettier-plugin-ember-template-tag:
         specifier: 'catalog:'
         version: 2.1.6(prettier@3.8.4)
-      rollup:
-        specifier: 'catalog:'
-        version: 4.62.0
-      rollup-plugin-copy:
-        specifier: 'catalog:'
-        version: 3.5.0
       svgo:
         specifier: 'catalog:'
         version: 3.3.3