diff --git a/lib/articlePublisher.ts b/lib/articlePublisher.ts
index 2361030..e7d1841 100644
--- a/lib/articlePublisher.ts
+++ b/lib/articlePublisher.ts
@@ -103,7 +103,7 @@ export class ArticlePublisher {
    * Send private content to a user after payment confirmation
    * Returns detailed result with message event ID and verification status
    */
-  private logSendResult(result: import('./articlePublisherHelpers').SendContentResult, articleId: string, recipientPubkey: string) {
+  private logSendResult(result: import('./articlePublisherHelpers').SendContentResult, articleId: string, recipientPubkey: string): void {
     if (result.success) {
       console.log('Private content sent successfully', {
         articleId,
diff --git a/lib/nostr.ts b/lib/nostr.ts
index f68fc20..d76c574 100644
--- a/lib/nostr.ts
+++ b/lib/nostr.ts
@@ -26,11 +26,11 @@ class NostrService {
     }
   }
 
-  private initializePool() {
+  private initializePool(): void {
     this.pool = new SimplePool()
   }
 
-  setPrivateKey(privateKey: string) {
+  setPrivateKey(privateKey: string): void {
     this.privateKey = privateKey
     try {
       const decoded = nip19.decode(privateKey)
@@ -50,7 +50,7 @@ class NostrService {
     return this.publicKey
   }
 
-  setPublicKey(publicKey: string) {
+  setPublicKey(publicKey: string): void {
     this.publicKey = publicKey
     try {
       const decoded = nip19.decode(publicKey)
@@ -85,7 +85,7 @@ class NostrService {
     }
   }
 
-  private createArticleSubscription(pool: SimplePool, limit: number) {
+  private createArticleSubscription(pool: SimplePool, limit: number): ReturnType<typeof createSubscription> {
     // Subscribe to both 'publication' and 'author' type events
     // Authors are identified by tag type='author' in the tag system
     // Filter by service='zapwall.fr' to only get notes from this platform
@@ -127,7 +127,7 @@ class NostrService {
 
     const sub = this.createArticleSubscription(this.pool, limit)
 
-    sub.on('event', async (event: Event) => {
+    sub.on('event', async (event: Event): Promise<void> => {
       try {
         // Try to parse as regular article first
         let article = await parseArticleFromEvent(event)
@@ -146,7 +146,7 @@ class NostrService {
       }
     })
 
-    return () => {
+    return (): void => {
       sub.unsub()
     }
   }