diff --git a/waku/src/general/mod.rs b/waku/src/general/mod.rs
index 3fbb5cd..289baac 100644
--- a/waku/src/general/mod.rs
+++ b/waku/src/general/mod.rs
@@ -3,6 +3,9 @@
 use serde::{Deserialize, Serialize};
 // internal
 
+pub type PubsubTopic = String;
+pub type ContentTopic = String;
+
 /// JsonResponse wrapper.
 /// `go-waku` ffi returns this type as a `char *` as per the [specification](https://rfc.vac.dev/spec/36/#jsonresponse-type)
 /// This is internal, as it is better to use rust plain `Result` type.
@@ -33,7 +36,7 @@ impl<T> From<JsonResponse<T>> for Response<T> {
 pub struct WakuMessage {
     payload: Box<[u8]>,
     /// The content topic to be set on the message
-    content_topic: String,
+    content_topic: ContentTopic,
     /// The Waku Message version number
     version: usize,
     /// Unix timestamp in nanoseconds
@@ -58,7 +61,7 @@ pub struct DecodedPayload {
 #[serde(rename_all = "camelCase")]
 pub struct ContentFilter {
     /// The content topic of a Waku message
-    content_topic: String,
+    content_topic: ContentTopic,
 }
 
 /// The criteria to create subscription to a light node in JSON Format
@@ -69,7 +72,7 @@ pub struct FilterSubscription {
     /// Array of [`ContentFilter`] being subscribed to / unsubscribed from
     content_filters: Vec<ContentFilter>,
     /// Optional pubsub topic
-    pubsub_topic: Option<String>,
+    pubsub_topic: Option<PubsubTopic>,
 }
 
 /// Criteria used to retrieve historical messages
@@ -77,7 +80,7 @@ pub struct FilterSubscription {
 #[serde(rename_all = "camelCase")]
 pub struct StoreQuery {
     /// The pubsub topic on which messages are published
-    pubsub_topic: Option<String>,
+    pubsub_topic: Option<PubsubTopic>,
     /// Array of [`ContentFilter`] to query for historical messages
     content_filters: Vec<ContentFilter>,
     /// The inclusive lower bound on the timestamp of queried messages.
@@ -124,5 +127,5 @@ pub struct MessageIndex {
     /// UNIX timestamp in nanoseconds at which the message is generated by its sender
     sender_time: usize,
     /// The pubsub topic of the message at this [`MessageIndex`]
-    pubsub_topic: String,
+    pubsub_topic: PubsubTopic,
 }