diff --git a/src/contact/mod.rs b/src/contact/mod.rs
index e69ec58..9eba279 100644
--- a/src/contact/mod.rs
+++ b/src/contact/mod.rs
@@ -5,14 +5,14 @@ pub struct Contact {
     #[serde(skip_serializing_if = "crate::init::is_uuid_nil")]
     pub id: Option<uuid::Uuid>,
     // empty?
-    #[serde(skip_serializing_if = "String::is_empty")]
-    pub firstname: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub firstname: Option<String>,
     // empty?
-    #[serde(skip_serializing_if = "String::is_empty")]
-    pub lastname: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub lastname: Option<String>,
     // empty?
-    #[serde(skip_serializing_if = "String::is_empty")]
-    pub nickname: String,
+    #[serde(skip_serializing_if = "Option::is_none")]
+    pub nickname: Option<String>,
     pub phone_number: String,
     // empty
     #[serde(skip_serializing_if = "crate::init::is_uuid_nil")]
diff --git a/src/lib.rs b/src/lib.rs
index 8d0b5f9..6dd050f 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -8,12 +8,8 @@ pub mod user;
 pub mod init {
     pub fn is_uuid_nil(uuid: &Option<uuid::Uuid>) -> bool {
         match uuid {
-            Some(id) => {
-                id.is_nil()
-            }
-            None => {
-                true
-            }
+            Some(id) => id.is_nil(),
+            None => true,
         }
     }
 }