diff --git a/lib/src/apigateway/openapi-gateway-lambda.test.ts b/lib/src/apigateway/openapi-gateway-lambda.test.ts
index 5637375..64f8bc0 100644
--- a/lib/src/apigateway/openapi-gateway-lambda.test.ts
+++ b/lib/src/apigateway/openapi-gateway-lambda.test.ts
@@ -7,8 +7,7 @@ import {
   extendZodWithOpenApi,
 } from '@asteasolutions/zod-to-openapi';
 import z from 'zod';
-import type { oas30, oas31 } from 'openapi3-ts';
-import { Converter } from '@apiture/openapi-down-convert';
+import { oas31 } from 'openapi3-ts';
 import {
   AccessLogFormat,
   EndpointType,
@@ -33,6 +32,7 @@ import {
   generateOperationId,
   getPropsWithDefaults,
   addLogGroupForTracing,
+  convertOpenapi31ToV30,
 } from './openapi-gateway-lambda';
 
 extendZodWithOpenApi(z);
@@ -309,20 +309,23 @@ describe('openapi-gateway-lambda', () => {
   });
 
   it('openapi lint should work', async () => {
+    const odoc31 = testOpenpidoc31();
+
     const f = (): void => {
-      lintOpenapiDocument(testOpenpidoc30(), true);
+      lintOpenapiDocument(convertOpenapi31ToV30(odoc31), true);
     };
     expect(f).not.toThrow();
   });
 
   it('openapi lint should fail', async () => {
-    const odoc = testOpenpidoc30();
+    const odoc31 = testOpenpidoc31();
+    const odoc30 = convertOpenapi31ToV30(odoc31);
 
     // fail if parameter ids in path and declaration doesn't match
     // @ts-ignore
-    odoc.paths['/users/{id}'].get.parameters[0].name = 'SOMETHING';
+    odoc30.paths['/users/{id}'].get.parameters[0].name = 'SOMETHING';
     const f = (): void => {
-      lintOpenapiDocument(odoc, true);
+      lintOpenapiDocument(odoc30, true);
     };
     expect(f).toThrow();
   });
@@ -744,17 +747,6 @@ const testGatewayProps = (): OpenApiGatewayLambdaProps => {
   };
 };
 
-const testOpenpidoc30 = (): oas30.OpenAPIObject => {
-  const odoc = testOpenpidoc31();
-  const converter = new Converter(odoc, {
-    verbose: false,
-    deleteExampleWithId: true,
-    allOfTransform: false,
-  });
-
-  return converter.convert() as oas30.OpenAPIObject;
-};
-
 const testOpenpidoc31 = (): oas31.OpenAPIObject => {
   const registry = new OpenAPIRegistry();
 
diff --git a/lib/src/apigateway/openapi-gateway-lambda.ts b/lib/src/apigateway/openapi-gateway-lambda.ts
index ca09042..3e6cc23 100644
--- a/lib/src/apigateway/openapi-gateway-lambda.ts
+++ b/lib/src/apigateway/openapi-gateway-lambda.ts
@@ -19,7 +19,7 @@ import { ArnFormat, ScopedAws, Size, Stack } from 'aws-cdk-lib/core';
 import { ILogGroup, LogGroup, RetentionDays } from 'aws-cdk-lib/aws-logs';
 import { ServicePrincipal } from 'aws-cdk-lib/aws-iam';
 import { OpenAPIRegistry, OpenApiGeneratorV31, RouteConfig } from '@asteasolutions/zod-to-openapi';
-import { Converter } from '@apiture/openapi-down-convert';
+import { Converter, ConverterOptions } from '@apiture/openapi-down-convert';
 
 import { lintOpenapiDocument } from '../utils/openapi-lint';
 import { randomId } from '../utils/misc';
@@ -64,13 +64,7 @@ export class OpenApiGatewayLambda extends Construct {
     }
 
     // AWS Gateway only supports openapi 3.0, so downconvert doc from 3.1 to 3.0
-    const converter = new Converter(openapiDoc31, {
-      verbose: false,
-      deleteExampleWithId: true,
-      allOfTransform: false,
-    });
-    const openapiDoc30 = converter.convert() as oas30.OpenAPIObject;
-
+    const openapiDoc30 = convertOpenapi31ToV30(openapiDoc31);
     lintOpenapiDocument(openapiDoc30, true);
 
     // The api gateway does not appends the stackname/stage into it by default
@@ -327,6 +321,22 @@ export const generateOpenapiDocWithExtensions = (
   return openapiDoc31;
 };
 
+// converts OpenAPI 3.1 document to OpenAPI 3.0
+export const convertOpenapi31ToV30 = (
+  openapiDoc31: oas31.OpenAPIObject,
+  converterOpts?: ConverterOptions,
+): oas30.OpenAPIObject => {
+  const converter = new Converter(
+    openapiDoc31,
+    converterOpts ?? {
+      verbose: false,
+      deleteExampleWithId: true,
+      allOfTransform: false,
+    },
+  );
+  return converter.convert() as oas30.OpenAPIObject;
+};
+
 export const getPropsWithDefaults = (
   id: string,
   props: OpenApiGatewayLambdaProps,
diff --git a/lib/src/index.ts b/lib/src/index.ts
index 31c384f..a7289ee 100644
--- a/lib/src/index.ts
+++ b/lib/src/index.ts
@@ -5,6 +5,7 @@ export * from './config/configs';
 export {
   OpenApiGatewayLambda,
   generateOpenapiDocWithExtensions,
+  convertOpenapi31ToV30,
 } from './apigateway/openapi-gateway-lambda';
 export * from './apigateway/types';