diff --git a/src/external/arbitrary_support.rs b/src/external/arbitrary_support.rs
index 53047dce..c753f74c 100644
--- a/src/external/arbitrary_support.rs
+++ b/src/external/arbitrary_support.rs
@@ -23,7 +23,7 @@ impl Arbitrary<'_> for Uuid {
 impl arbitrary::Arbitrary<'_> for NonNilUuid {
     fn arbitrary(u: &mut arbitrary::Unstructured<'_>) -> arbitrary::Result<Self> {
         let uuid = Uuid::arbitrary(u)?;
-        Self::try_from(uuid).map_err(|_| arbitrary::Error::NotEnoughData)
+        Self::try_from(uuid).map_err(|_| arbitrary::Error::IncorrectFormat)
     }
 
     fn size_hint(_: usize) -> (usize, Option<usize>) {
diff --git a/src/external/serde_support.rs b/src/external/serde_support.rs
index 42c06493..954a3496 100644
--- a/src/external/serde_support.rs
+++ b/src/external/serde_support.rs
@@ -145,7 +145,7 @@ impl<'de> Deserialize<'de> for NonNilUuid {
     {
         let uuid = Uuid::deserialize(deserializer)?;
 
-        NonNilUuid::try_from(uuid).map_err(|_| de::Error::custom("Uuid cannot be nil"))
+        NonNilUuid::try_from(uuid).map_err(|_| de::Error::invalid_value(de::Unexpected::Other("nil UUID"), &"a non-nil UUID"))
     }
 }
 
diff --git a/src/lib.rs b/src/lib.rs
index 1c30c383..d9d772cf 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -437,6 +437,7 @@ pub enum Variant {
 ///
 /// The `Uuid` type is always guaranteed to be have the same ABI as [`Bytes`].
 #[derive(Clone, Copy, Eq, Hash, Ord, PartialEq, PartialOrd)]
+#[repr(transparent)]
 #[cfg_attr(
     all(uuid_unstable, feature = "zerocopy"),
     derive(IntoBytes, FromBytes, KnownLayout, Immutable, Unaligned)
@@ -445,7 +446,6 @@ pub enum Variant {
     feature = "borsh",
     derive(borsh_derive::BorshDeserialize, borsh_derive::BorshSerialize)
 )]
-#[repr(transparent)]
 #[cfg_attr(
     feature = "bytemuck",
     derive(bytemuck::Zeroable, bytemuck::Pod, bytemuck::TransparentWrapper)
diff --git a/src/non_nil.rs b/src/non_nil.rs
index 71db073e..f88fd1a2 100644
--- a/src/non_nil.rs
+++ b/src/non_nil.rs
@@ -26,6 +26,15 @@ use crate::{
 /// - [`Uuid::new_v7`]
 /// - [`Uuid::now_v7`]
 /// - [`Uuid::new_v8`]
+#[cfg_attr(
+    all(uuid_unstable, feature = "zerocopy"),
+    derive(IntoBytes, FromBytes, KnownLayout, Immutable, Unaligned)
+)]
+#[cfg_attr(
+    feature = "borsh",
+    derive(borsh_derive::BorshDeserialize, borsh_derive::BorshSerialize)
+)]
+#[repr(transparent)]
 #[derive(Debug, Copy, Clone, PartialEq, Eq, Hash)]
 pub struct NonNilUuid(NonZeroU128);