diff --git a/src/activitypub.rs b/src/activitypub.rs
index 5002eec..1f1417d 100644
--- a/src/activitypub.rs
+++ b/src/activitypub.rs
@@ -11,7 +11,7 @@ pub struct Actor {
     pub name: Option<String>,
     pub icon: Option<Media>,
     pub inbox: String,
-    pub outbox: String,
+    pub outbox: Option<String>,
     #[serde(rename = "publicKey")]
     pub public_key: ActorPublicKey,
     #[serde(rename = "preferredUsername")]
@@ -49,8 +49,8 @@ impl IntoResponse for Actor {
 #[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct Media {
     #[serde(rename = "type")]
-    pub media_type: String,
+    pub media_type: Option<String>,
     #[serde(rename = "mediaType")]
-    pub content_type: String,
+    pub content_type: Option<String>,
     pub url: String,
 }
diff --git a/src/actor.rs b/src/actor.rs
index 843e4ee..ad8de30 100644
--- a/src/actor.rs
+++ b/src/actor.rs
@@ -51,12 +51,12 @@ impl Actor {
                     instance.to_string(),
             }),
             icon: Some(activitypub::Media {
-                media_type: "Image".to_string(),
-                content_type: "image/jpeg".to_string(),
+                media_type: Some("Image".to_string()),
+                content_type: Some("image/jpeg".to_string()),
                 url: "https://fedi.buzz/assets/favicon48.png".to_string(),
             }),
             inbox: self.uri(),
-            outbox: format!("{}/outbox", self.uri()),
+            outbox: Some(format!("{}/outbox", self.uri())),
             public_key: activitypub::ActorPublicKey {
                 id: self.key_id(),
                 owner: Some(self.uri()),