diff --git a/playground/vitest.config.ts b/playground/vitest.config.ts
new file mode 100644
index 0000000..080b534
--- /dev/null
+++ b/playground/vitest.config.ts
@@ -0,0 +1,7 @@
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    include: ['./**/*.test.ts'],
+  },
+})
diff --git a/vitest.config.ts b/vitest.config.ts
new file mode 100644
index 0000000..3e42797
--- /dev/null
+++ b/vitest.config.ts
@@ -0,0 +1,7 @@
+import { defineConfig } from 'vitest/config'
+
+export default defineConfig({
+  test: {
+    include: ['test/**/*.test.ts'],
+  },
+})