diff --git a/packages/settings/settings/tsdown.config.ts b/packages/settings/settings/tsdown.config.ts
new file mode 100644
index 0000000000..e92275a7f5
--- /dev/null
+++ b/packages/settings/settings/tsdown.config.ts
@@ -0,0 +1,25 @@
+import { defineConfig } from 'tsdown'
+
+/** Build the package root and optional invariant companion as independent bundles. */
+export default defineConfig([
+  {
+    entry: ['lib/types/index.js'],
+    outDir: 'lib',
+    format: ['esm'],
+    platform: 'node',
+    target: 'es2024',
+    fixedExtension: false,
+    dts: false,
+    clean: false,
+  },
+  {
+    entry: ['lib/types/invariant.js'],
+    outDir: 'lib',
+    format: ['esm'],
+    platform: 'node',
+    target: 'es2024',
+    fixedExtension: false,
+    dts: false,
+    clean: false,
+  },
+])