diff --git a/package-lock.json b/package-lock.json
index 08a6f78..c197640 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,12 +1,12 @@
 {
   "name": "@envoy/envoy-integrations-sdk",
-  "version": "2.3.6",
+  "version": "2.4.0-beta.5",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "@envoy/envoy-integrations-sdk",
-      "version": "2.3.6",
+      "version": "2.4.0-beta.5",
       "license": "ISC",
       "dependencies": {
         "@types/dotenv": "^8.2.0",
diff --git a/package.json b/package.json
index 3130d13..aa4f51d 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@envoy/envoy-integrations-sdk",
-  "version": "2.3.6",
+  "version": "2.4.0-beta.5",
   "description": "SDK for building Envoy integrations.",
   "main": "dist/index.js",
   "types": "dist/index.d.ts",
diff --git a/src/sdk/middleware.ts b/src/sdk/middleware.ts
index f2f31f5..878286e 100644
--- a/src/sdk/middleware.ts
+++ b/src/sdk/middleware.ts
@@ -9,6 +9,16 @@ import EnvoyPluginJobAttachment from './EnvoyPluginJobAttachment';
 import EnvoyPluginSDK from './EnvoyPluginSDK';
 import EnvoyPluginAPI from './EnvoyPluginAPI';
 
+/**
+ * Options for configuring the Envoy middleware.
+ */
+export interface EnvoyMiddlewareOptions extends Partial<EnvoySignatureVerifierOptions> {
+  /** Optional custom client ID to use for API authentication instead of environment variable */
+  customClientId?: string;
+  /** Optional custom client secret to use for API authentication instead of environment variable */
+  customClientSecret?: string;
+}
+
 /**
  * Sets up an {@link EnvoyPluginSDK} object in the path `req.envoy`.
  * Modifies the `res` object to include Envoy's helpers, per {@link EnvoyResponse}.
@@ -18,8 +28,8 @@ import EnvoyPluginAPI from './EnvoyPluginAPI';
  *
  * @category Middleware
  */
-export function envoyMiddleware(options?: EnvoySignatureVerifierOptions): RequestHandler {
-  const signatureVerifier = new EnvoySignatureVerifier(options);
+export function envoyMiddleware(options?: EnvoyMiddlewareOptions): RequestHandler {
+  const signatureVerifier = new EnvoySignatureVerifier(options as EnvoySignatureVerifierOptions);
   const verify = (req: VerifiedRequest, res: Response, rawBody: Buffer) => {
     req[VERIFIED] = signatureVerifier.verify(req, rawBody);
   };
@@ -35,7 +45,10 @@ export function envoyMiddleware(options?: EnvoySignatureVerifierOptions): Reques
       try {
         const now = Date.now();
         if (now > threshold) {
-          const { access_token: rawAccessToken, expires_in: expiresIn } = await EnvoyPluginAPI.loginAsPlugin();
+          const hasCustomCredentials = options?.customClientId && options?.customClientSecret;
+          const { access_token: rawAccessToken, expires_in: expiresIn } = hasCustomCredentials
+            ? await EnvoyPluginAPI.loginAsPlugin(options?.customClientId, options?.customClientSecret)
+            : await EnvoyPluginAPI.loginAsPlugin();
           accessToken = rawAccessToken;
           threshold = now + expiresIn * 1000 - 1000 * 60 * 10;
         }
@@ -101,3 +114,9 @@ export function errorMiddleware(onError: (err: Error) => void = () => {}): Error
     res.end(JSON.stringify({ message: err.message }));
   };
 }
+
+/**
+ * Backward compatibility alias for envoyMiddleware
+ * @deprecated Use envoyMiddleware instead
+ */
+export const middleware = envoyMiddleware;