diff --git a/packages/codegen-core/tsconfig.base.json b/packages/codegen-core/tsconfig.base.json
index 5afc381fb..88574f242 100644
--- a/packages/codegen-core/tsconfig.base.json
+++ b/packages/codegen-core/tsconfig.base.json
@@ -10,7 +10,7 @@
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "strict": true,
-    "target": "ES2022",
+    "target": "ES2021",
     "useUnknownInCatchVariables": false
   }
 }
diff --git a/packages/codegen-core/tsup.config.ts b/packages/codegen-core/tsup.config.ts
index dec56b5a0..e22a03b78 100644
--- a/packages/codegen-core/tsup.config.ts
+++ b/packages/codegen-core/tsup.config.ts
@@ -21,5 +21,6 @@ export default defineConfig((options) => ({
   minify: !options.watch,
   shims: false,
   sourcemap: true,
+  target: 'node18',
   treeshake: true,
 }));
diff --git a/packages/openapi-ts/bin/index.cjs b/packages/openapi-ts/bin/index.cjs
index 79e93dd59..d854db670 100755
--- a/packages/openapi-ts/bin/index.cjs
+++ b/packages/openapi-ts/bin/index.cjs
@@ -139,7 +139,8 @@ async function start() {
     ) {
       process.exit(0);
     }
-  } catch {
+  } catch (error) {
+    console.error(error);
     process.exit(1);
   }
 }
diff --git a/packages/openapi-ts/src/config/__tests__/engine.test.ts b/packages/openapi-ts/src/config/__tests__/engine.test.ts
new file mode 100644
index 000000000..31055164e
--- /dev/null
+++ b/packages/openapi-ts/src/config/__tests__/engine.test.ts
@@ -0,0 +1,77 @@
+import fs from 'node:fs';
+import path from 'node:path';
+
+import { describe, expect, it } from 'vitest';
+
+import { checkNodeVersion } from '../engine';
+
+describe('engine config', () => {
+  describe('checkNodeVersion', () => {
+    it('should not throw error for Node 18+', () => {
+      expect(() => checkNodeVersion()).not.toThrow();
+    });
+  });
+
+  describe('Node 18 compatibility', () => {
+    it('should have TypeScript target set to ES2021 for Node 18 compatibility', () => {
+      const tsconfigPath = path.resolve(
+        __dirname,
+        '..',
+        '..',
+        '..',
+        'tsconfig.base.json',
+      );
+      const tsconfig = JSON.parse(fs.readFileSync(tsconfigPath, 'utf8'));
+
+      // ES2021 is required for Node 18 compatibility
+      // ES2022 includes features like Object.hasOwn that are not available in Node 18
+      expect(tsconfig.compilerOptions.target).toBe('ES2021');
+    });
+
+    it('should have tsup target set to node18 for Node 18 compatibility', () => {
+      const tsupConfigPath = path.resolve(
+        __dirname,
+        '..',
+        '..',
+        '..',
+        'tsup.config.ts',
+      );
+      const tsupConfig = fs.readFileSync(tsupConfigPath, 'utf8');
+
+      // tsup/esbuild needs explicit node18 target to ensure compiled output works on Node 18
+      expect(tsupConfig).toContain("target: 'node18'");
+    });
+
+    it('should have TypeScript target set to ES2021 in codegen-core for Node 18 compatibility', () => {
+      const tsconfigPath = path.resolve(
+        __dirname,
+        '..',
+        '..',
+        '..',
+        '..',
+        'codegen-core',
+        'tsconfig.base.json',
+      );
+      const tsconfig = JSON.parse(fs.readFileSync(tsconfigPath, 'utf8'));
+
+      // ES2021 is required for Node 18 compatibility
+      expect(tsconfig.compilerOptions.target).toBe('ES2021');
+    });
+
+    it('should have tsup target set to node18 in codegen-core for Node 18 compatibility', () => {
+      const tsupConfigPath = path.resolve(
+        __dirname,
+        '..',
+        '..',
+        '..',
+        '..',
+        'codegen-core',
+        'tsup.config.ts',
+      );
+      const tsupConfig = fs.readFileSync(tsupConfigPath, 'utf8');
+
+      // tsup/esbuild needs explicit node18 target to ensure compiled output works on Node 18
+      expect(tsupConfig).toContain("target: 'node18'");
+    });
+  });
+});
diff --git a/packages/openapi-ts/tsconfig.base.json b/packages/openapi-ts/tsconfig.base.json
index 5afc381fb..88574f242 100644
--- a/packages/openapi-ts/tsconfig.base.json
+++ b/packages/openapi-ts/tsconfig.base.json
@@ -10,7 +10,7 @@
     "noUnusedLocals": true,
     "noUnusedParameters": true,
     "strict": true,
-    "target": "ES2022",
+    "target": "ES2021",
     "useUnknownInCatchVariables": false
   }
 }
diff --git a/packages/openapi-ts/tsup.config.ts b/packages/openapi-ts/tsup.config.ts
index 5cef330f1..49d20b9cd 100644
--- a/packages/openapi-ts/tsup.config.ts
+++ b/packages/openapi-ts/tsup.config.ts
@@ -72,5 +72,6 @@ export default defineConfig((options) => ({
   },
   shims: false,
   sourcemap: true,
+  target: 'node18',
   treeshake: true,
 }));