diff --git a/packages/pubsub/src/lib/client.ts b/packages/pubsub/src/lib/client.ts
index de35d68b..a3d484f3 100644
--- a/packages/pubsub/src/lib/client.ts
+++ b/packages/pubsub/src/lib/client.ts
@@ -5,15 +5,10 @@ export type ClientConfig = {
   projectId: string
 }
 
-const localProjectId: string = 'local'
+const localProjectId = 'local'
 const clients: Record<string, PubSub> = {}
 
-const init = (config?: ClientConfig) => {
-  let projectId: string = localProjectId
-  if (config && config.projectId) {
-    projectId = config.projectId
-  }
-
+const init = ({ projectId }: ClientConfig = { projectId: localProjectId }) => {
   if (!clients[projectId]) {
     if (projectId === localProjectId) {
       // Create a default client when there is no config.
diff --git a/packages/pubsub/src/lib/pubsub.spec.ts b/packages/pubsub/src/lib/pubsub.spec.ts
index d06df1ac..02a96669 100644
--- a/packages/pubsub/src/lib/pubsub.spec.ts
+++ b/packages/pubsub/src/lib/pubsub.spec.ts
@@ -143,7 +143,9 @@ describe('creates an instance of PubSub', () => {
 
       await createdPubsub.topic(topicName, mockConfig).publish(topicData)
 
-      expect(PubSub).toHaveBeenCalledWith(mockConfig)
+      expect(PubSub).toHaveBeenCalledWith({
+        projectId: mockConfig.projectId,
+      })
     })
 
     it('when subscribing', async () => {
@@ -154,7 +156,9 @@ describe('creates an instance of PubSub', () => {
         onSuccess: () => undefined,
       })
 
-      expect(PubSub).toHaveBeenCalledWith(mockConfig)
+      expect(PubSub).toHaveBeenCalledWith({
+        projectId: mockConfig.projectId,
+      })
     })
   })
 })