diff --git a/index.d.ts b/index.d.ts
index 13396202..efccf214 100644
--- a/index.d.ts
+++ b/index.d.ts
@@ -23,9 +23,20 @@ import { Readable } from 'stream'
 type Mercurius = typeof mercurius
 
 declare namespace mercurius {
-  export interface PubSub {
-    subscribe<TResult = any>(topics: string | string[]): Promise<Readable & AsyncIterableIterator<TResult>>;
-    publish<TResult = any>(event: { topic: string; payload: TResult }, callback?: () => void): void;
+  export type PubSubPublishArgsByKey = {
+    [key: string]: any;
+  };
+
+  export interface PubSub<
+    TPubSubPublishArgsByKey extends PubSubPublishArgsByKey,
+  > {
+      subscribe<TKey extends Extract<keyof TPubSubPublishArgsByKey, string>>(
+        topics: TKey | TKey[],
+      ): Promise<Readable & AsyncIterableIterator<TPubSubPublishArgsByKey[TKey]>>;
+      publish<TKey extends Extract<keyof TPubSubPublishArgsByKey, string>>(
+        event: { topic: TKey; payload: TPubSubPublishArgsByKey[TKey] },
+        callback?: () => void,
+      ): void;
   }
 
   export interface MercuriusContext {
diff --git a/package.json b/package.json
index b214dca9..58568ddb 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "mercurius",
-  "version": "14.1.0",
+  "version": "15.0.0",
   "description": "Fastify GraphQL adapter with subscription support",
   "main": "index.js",
   "types": "index.d.ts",