diff --git a/runtime_tests/lambda/index.test.ts b/runtime_tests/lambda/index.test.ts
index 475200c36..8da3afc3c 100644
--- a/runtime_tests/lambda/index.test.ts
+++ b/runtime_tests/lambda/index.test.ts
@@ -1,11 +1,11 @@
 import { Readable } from 'stream'
+import { handle, streamHandle } from '../../src/adapter/aws-lambda/handler'
+import type { LambdaEvent } from '../../src/adapter/aws-lambda/handler'
 import type {
   ApiGatewayRequestContext,
   ApiGatewayRequestContextV2,
-} from '../../src/adapter/aws-lambda/custom-context'
-import { handle, streamHandle } from '../../src/adapter/aws-lambda/handler'
-import type { LambdaEvent } from '../../src/adapter/aws-lambda/handler'
-import type { LambdaContext } from '../../src/adapter/aws-lambda/types'
+  LambdaContext,
+} from '../../src/adapter/aws-lambda/types'
 import { getCookie, setCookie } from '../../src/helper/cookie'
 import { streamSSE } from '../../src/helper/streaming'
 import { Hono } from '../../src/hono'
diff --git a/src/adapter/aws-lambda/custom-context.ts b/src/adapter/aws-lambda/custom-context.ts
deleted file mode 100644
index b9dd48e26..000000000
--- a/src/adapter/aws-lambda/custom-context.ts
+++ /dev/null
@@ -1,87 +0,0 @@
-interface ClientCert {
-  clientCertPem: string
-  subjectDN: string
-  issuerDN: string
-  serialNumber: string
-  validity: {
-    notBefore: string
-    notAfter: string
-  }
-}
-
-interface Identity {
-  accessKey?: string
-  accountId?: string
-  caller?: string
-  cognitoAuthenticationProvider?: string
-  cognitoAuthenticationType?: string
-  cognitoIdentityId?: string
-  cognitoIdentityPoolId?: string
-  principalOrgId?: string
-  sourceIp: string
-  user?: string
-  userAgent: string
-  userArn?: string
-  clientCert?: ClientCert
-}
-
-export interface ApiGatewayRequestContext {
-  accountId: string
-  apiId: string
-  authorizer: {
-    claims?: unknown
-    scopes?: unknown
-  }
-  domainName: string
-  domainPrefix: string
-  extendedRequestId: string
-  httpMethod: string
-  identity: Identity
-  path: string
-  protocol: string
-  requestId: string
-  requestTime: string
-  requestTimeEpoch: number
-  resourceId?: string
-  resourcePath: string
-  stage: string
-}
-
-interface Authorizer {
-  iam?: {
-    accessKey: string
-    accountId: string
-    callerId: string
-    cognitoIdentity: null
-    principalOrgId: null
-    userArn: string
-    userId: string
-  }
-}
-
-export interface ApiGatewayRequestContextV2 {
-  accountId: string
-  apiId: string
-  authentication: null
-  authorizer: Authorizer
-  domainName: string
-  domainPrefix: string
-  http: {
-    method: string
-    path: string
-    protocol: string
-    sourceIp: string
-    userAgent: string
-  }
-  requestId: string
-  routeKey: string
-  stage: string
-  time: string
-  timeEpoch: number
-}
-
-export interface ALBRequestContext {
-  elb: {
-    targetGroupArn: string
-  }
-}
diff --git a/src/adapter/aws-lambda/handler.ts b/src/adapter/aws-lambda/handler.ts
index e9d30e835..efb85eede 100644
--- a/src/adapter/aws-lambda/handler.ts
+++ b/src/adapter/aws-lambda/handler.ts
@@ -6,8 +6,9 @@ import type {
   ALBRequestContext,
   ApiGatewayRequestContext,
   ApiGatewayRequestContextV2,
-} from './custom-context'
-import type { Handler, LambdaContext } from './types'
+  Handler,
+  LambdaContext,
+} from './types'
 
 // eslint-disable-next-line @typescript-eslint/ban-ts-comment
 // @ts-ignore
diff --git a/src/adapter/aws-lambda/index.ts b/src/adapter/aws-lambda/index.ts
index 893bce23a..74d0a09ad 100644
--- a/src/adapter/aws-lambda/index.ts
+++ b/src/adapter/aws-lambda/index.ts
@@ -9,5 +9,5 @@ export type {
   ApiGatewayRequestContext,
   ApiGatewayRequestContextV2,
   ALBRequestContext,
-} from './custom-context'
-export type { LambdaContext } from './types'
+  LambdaContext,
+} from './types'
diff --git a/src/adapter/aws-lambda/types.ts b/src/adapter/aws-lambda/types.ts
index d1054a7e0..d1ec95ebf 100644
--- a/src/adapter/aws-lambda/types.ts
+++ b/src/adapter/aws-lambda/types.ts
@@ -54,3 +54,91 @@ export type Handler<TEvent = any, TResult = any> = (
   context: LambdaContext,
   callback: Callback<TResult>
 ) => void | Promise<TResult>
+
+interface ClientCert {
+  clientCertPem: string
+  subjectDN: string
+  issuerDN: string
+  serialNumber: string
+  validity: {
+    notBefore: string
+    notAfter: string
+  }
+}
+
+interface Identity {
+  accessKey?: string
+  accountId?: string
+  caller?: string
+  cognitoAuthenticationProvider?: string
+  cognitoAuthenticationType?: string
+  cognitoIdentityId?: string
+  cognitoIdentityPoolId?: string
+  principalOrgId?: string
+  sourceIp: string
+  user?: string
+  userAgent: string
+  userArn?: string
+  clientCert?: ClientCert
+}
+
+export interface ApiGatewayRequestContext {
+  accountId: string
+  apiId: string
+  authorizer: {
+    claims?: unknown
+    scopes?: unknown
+  }
+  domainName: string
+  domainPrefix: string
+  extendedRequestId: string
+  httpMethod: string
+  identity: Identity
+  path: string
+  protocol: string
+  requestId: string
+  requestTime: string
+  requestTimeEpoch: number
+  resourceId?: string
+  resourcePath: string
+  stage: string
+}
+
+interface Authorizer {
+  iam?: {
+    accessKey: string
+    accountId: string
+    callerId: string
+    cognitoIdentity: null
+    principalOrgId: null
+    userArn: string
+    userId: string
+  }
+}
+
+export interface ApiGatewayRequestContextV2 {
+  accountId: string
+  apiId: string
+  authentication: null
+  authorizer: Authorizer
+  domainName: string
+  domainPrefix: string
+  http: {
+    method: string
+    path: string
+    protocol: string
+    sourceIp: string
+    userAgent: string
+  }
+  requestId: string
+  routeKey: string
+  stage: string
+  time: string
+  timeEpoch: number
+}
+
+export interface ALBRequestContext {
+  elb: {
+    targetGroupArn: string
+  }
+}