diff --git a/package.json b/package.json
index 8476263..7df53fb 100644
--- a/package.json
+++ b/package.json
@@ -21,7 +21,7 @@
     "axios": "^0.27.2",
     "js-yaml": "^4.1.0",
     "json-schema-to-typescript": "^10.1.5",
-    "openapi-types": "^11.0.1",
+    "openapi-types": "^12.1.3",
     "yargs": "^17.5.1",
     "zod-to-json-schema": "^3.20.2",
     "zod-validation-error": "^0.3.0"
@@ -47,13 +47,13 @@
     "jest": "^28.1.0",
     "koa": "^2.13.4",
     "koa-bodyparser": "^4.3.0",
-    "openapi-schema-validator": "^11.0.1",
+    "openapi-schema-validator": "^12.1.3",
     "prettier": "^2.6.2",
     "semantic-release": "^19.0.3",
     "tmp": "^0.2.1",
     "ts-jest": "^28.0.3",
     "ts-node": "^10.8.0",
-    "typescript": "^4.7.2",
+    "typescript": "^5.1.6",
     "uuid": "^9.0.0",
     "zod": "^3.20.2"
   }
diff --git a/src/koa.ts b/src/koa.ts
index 54ef06e..857c447 100644
--- a/src/koa.ts
+++ b/src/koa.ts
@@ -70,27 +70,6 @@ export type ImplementationConfig<
 
 const ajv = new Ajv();
 
-const defaultParse: ImplementationConfig<any, any>['parse'] = (
-  ctx,
-  { endpoint, data, schema },
-) => {
-  if (!ajv.validate(schema, data)) {
-    const method = (endpoint as string).split(' ')[0];
-    const dataVar = ['GET', 'DELETE'].includes(method)
-      ? 'query parameters'
-      : 'payload';
-
-    return ctx.throw(
-      400,
-      `The request did not conform to the required schema: ${ajv.errorsText(
-        undefined,
-        { dataVar },
-      )}`,
-    );
-  }
-  return data as any;
-};
-
 /**
  * Implements the specified `schema` on the provided router object.
  *
@@ -113,12 +92,33 @@ export const implementSchema = <
     addIntrospection(introspection, () => schema, router);
   }
 
+  const defaultParse: ImplementationConfig<Schema, RouterType>['parse'] = (
+    ctx,
+    { endpoint, data, schema },
+  ) => {
+    if (!ajv.validate(schema, data)) {
+      const method = (endpoint as string).split(' ')[0];
+      const dataVar = ['GET', 'DELETE'].includes(method)
+        ? 'query parameters'
+        : 'payload';
+
+      return ctx.throw(
+        400,
+        `The request did not conform to the required schema: ${ajv.errorsText(
+          undefined,
+          { dataVar },
+        )}`,
+      );
+    }
+    return data;
+  };
+
   // Iterate through every handler, and add a route for it based on
   // the key/route description.
   for (const endpoint in implementation) {
     const routeHandler = implementation[endpoint];
 
-    const parser: typeof parse = parse ?? defaultParse;
+    const parser = parse ?? defaultParse;
 
     implementRoute(
       endpoint,
diff --git a/yarn.lock b/yarn.lock
index 33783aa..b5bc74a 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -5894,20 +5894,20 @@ only@~0.0.2:
   resolved "https://registry.yarnpkg.com/only/-/only-0.0.2.tgz#2afde84d03e50b9a8edc444e30610a70295edfb4"
   integrity sha1-Kv3oTQPlC5qO3EROMGEKcCle37Q=
 
-openapi-schema-validator@^11.0.1:
-  version "11.0.1"
-  resolved "https://registry.yarnpkg.com/openapi-schema-validator/-/openapi-schema-validator-11.0.1.tgz#430ca95e02b79f9750b57f51051a1f97af30248c"
-  integrity sha512-c2+6qqsIZ2rX5CrxrW7QjsDYNw/fA1XPMBq/dMeU+k/I1y6GSbl64jutbLaLhEORd2coavga16eeYx3GtmkWKQ==
+openapi-schema-validator@^12.1.3:
+  version "12.1.3"
+  resolved "https://registry.yarnpkg.com/openapi-schema-validator/-/openapi-schema-validator-12.1.3.tgz#c9234af67b00cdbbecfdd4eb546d7006bacfe518"
+  integrity sha512-xTHOmxU/VQGUgo7Cm0jhwbklOKobXby+/237EG967+3TQEYJztMgX9Q5UE2taZKwyKPUq0j11dngpGjUuxz1hQ==
   dependencies:
     ajv "^8.1.0"
     ajv-formats "^2.0.2"
     lodash.merge "^4.6.1"
-    openapi-types "^11.0.1"
+    openapi-types "^12.1.3"
 
-openapi-types@^11.0.1:
-  version "11.0.1"
-  resolved "https://registry.yarnpkg.com/openapi-types/-/openapi-types-11.0.1.tgz#7e1cee2c9b8cb16787d14f2b0f433c5ba0e32e96"
-  integrity sha512-P2pGRlHFXgP8z6vrp5P/MtftOXYtlIY1A+V0VmioOoo85NN6RSPgGbEprRAUNMIsbfRjnCPdx/r8mi8QRR7grQ==
+openapi-types@^12.1.3:
+  version "12.1.3"
+  resolved "https://registry.yarnpkg.com/openapi-types/-/openapi-types-12.1.3.tgz#471995eb26c4b97b7bd356aacf7b91b73e777dd3"
+  integrity sha512-N4YtSYJqghVu4iek2ZUvcN/0aqH1kRDuNqzcycDxhOUpg7GdvLa2F3DgS6yBNhInhv2r/6I0Flkn7CqL8+nIcw==
 
 opener@^1.5.2:
   version "1.5.2"
@@ -7143,10 +7143,10 @@ type@^2.5.0:
   resolved "https://registry.yarnpkg.com/type/-/type-2.6.0.tgz#3ca6099af5981d36ca86b78442973694278a219f"
   integrity sha512-eiDBDOmkih5pMbo9OqsqPRGMljLodLcwd5XD5JbtNB0o89xZAwynY9EdCDsJU7LtcVCClu9DvM7/0Ep1hYX3EQ==
 
-typescript@^4.7.2:
-  version "4.7.2"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.7.2.tgz#1f9aa2ceb9af87cca227813b4310fff0b51593c4"
-  integrity sha512-Mamb1iX2FDUpcTRzltPxgWMKy3fhg0TN378ylbktPGPK/99KbDtMQ4W1hwgsbPAsG3a0xKa1vmw4VKZQbkvz5A==
+typescript@^5.1.6:
+  version "5.1.6"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-5.1.6.tgz#02f8ac202b6dad2c0dd5e0913745b47a37998274"
+  integrity sha512-zaWCozRZ6DLEWAWFrVDz1H6FVXzUSfTy5FUMWsQlU8Ym5JP9eO4xkTIROFCQvhQf61z6O/G6ugw3SgAnvvm+HA==
 
 uglify-js@^3.1.4:
   version "3.15.5"