diff --git a/microdroid/payload/config/src/lib.rs b/microdroid/payload/config/src/lib.rs
index 925a543..cdef3e4 100644
--- a/microdroid/payload/config/src/lib.rs
+++ b/microdroid/payload/config/src/lib.rs
@@ -64,10 +64,11 @@
 
 /// Payload's task can be one of plain executable
 /// or an .so library which can be started via /system/bin/microdroid_launcher
-#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]
+#[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize, Default)]
 pub enum TaskType {
     /// Task's command indicates the path to the executable binary.
     #[serde(rename = "executable")]
+    #[default]
     Executable,
     /// Task's command indicates the .so library in /mnt/apk/lib/{arch}
     #[serde(rename = "microdroid_launcher")]
@@ -87,12 +88,6 @@
     pub command: String,
 }
 
-impl Default for TaskType {
-    fn default() -> TaskType {
-        TaskType::Executable
-    }
-}
-
 /// APEX config
 /// For now, we only pass the name of APEX.
 #[derive(Clone, Debug, Deserialize, Eq, PartialEq, Serialize)]