diff --git a/package.json b/package.json
index ea6f679..703f798 100644
--- a/package.json
+++ b/package.json
@@ -18,7 +18,7 @@
     "lint": "eslint --ext .ts,.js .",
     "prepack": "pnpm unbuild",
     "release": "pnpm test && standard-version && git push --follow-tags && npm publish",
-    "stub": "pnpm unbuild -- --stub",
+    "stub": "pnpm unbuild --stub",
     "test": "mocha -r jiti/register ./test/*.test.*",
     "unbuild": "jiti ./src/cli"
   },
diff --git a/src/build.ts b/src/build.ts
index 8269d09..0974dd4 100644
--- a/src/build.ts
+++ b/src/build.ts
@@ -3,7 +3,7 @@ import { resolve, basename } from 'pathe'
 import type { PackageJson } from 'pkg-types'
 import chalk from 'chalk'
 import consola from 'consola'
-import defu from 'defu'
+import { defu } from 'defu'
 import { createHooks } from 'hookable'
 import prettyBytes from 'pretty-bytes'
 import mkdirp from 'mkdirp'
diff --git a/src/builder/rollup.ts b/src/builder/rollup.ts
index 5c9a75b..7cb91d7 100644
--- a/src/builder/rollup.ts
+++ b/src/builder/rollup.ts
@@ -70,7 +70,7 @@ export async function rollupBuild (ctx: BuildContext) {
       if (entry.isEntry) {
         ctx.buildEntries.push({
           path: relative(ctx.options.rootDir, resolve(outputOptions.dir!, entry.fileName)),
-          bytes: entry.code.length * 4,
+          bytes: Buffer.byteLength(entry.code, 'utf8'),
           exports: entry.exports
         })
       }