diff --git a/libs/apkverify/src/algorithms.rs b/libs/apkverify/src/algorithms.rs
index 442b47c..c05ab38 100644
--- a/libs/apkverify/src/algorithms.rs
+++ b/libs/apkverify/src/algorithms.rs
@@ -204,9 +204,10 @@
 }
 
 /// Hash algorithms.
-#[derive(Clone, Copy, Debug, PartialEq, Eq, FromPrimitive, ToPrimitive)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq, FromPrimitive, ToPrimitive, Default)]
 #[repr(u32)]
 pub enum HashAlgorithm {
+    #[default]
     /// SHA-256
     SHA256 = 1,
 }
@@ -217,9 +218,3 @@
         Self::from_u32(val).context(format!("Unsupported hash algorithm: {}", val))
     }
 }
-
-impl Default for HashAlgorithm {
-    fn default() -> Self {
-        HashAlgorithm::SHA256
-    }
-}
diff --git a/libs/apkverify/src/v4.rs b/libs/apkverify/src/v4.rs
index 94abf99..e77ad77 100644
--- a/libs/apkverify/src/v4.rs
+++ b/libs/apkverify/src/v4.rs
@@ -104,9 +104,10 @@
 }
 
 /// Version of the idsig file format
-#[derive(Debug, PartialEq, Eq, FromPrimitive, ToPrimitive)]
+#[derive(Debug, PartialEq, Eq, FromPrimitive, ToPrimitive, Default)]
 #[repr(u32)]
 pub enum Version {
+    #[default]
     /// Version 2, the only supported version.
     V2 = 2,
 }
@@ -117,12 +118,6 @@
     }
 }
 
-impl Default for Version {
-    fn default() -> Self {
-        Version::V2
-    }
-}
-
 impl V4Signature<fs::File> {
     /// Creates a `V4Signature` struct from the given idsig path.
     pub fn from_idsig_path<P: AsRef<Path>>(idsig_path: P) -> Result<Self> {
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)]