diff --git a/crates/gordian-lexicon/src/extra/objectid.rs b/crates/gordian-lexicon/src/extra/objectid.rs
index 73cc00a..51c6d7f 100644
--- a/crates/gordian-lexicon/src/extra/objectid.rs
+++ b/crates/gordian-lexicon/src/extra/objectid.rs
@@ -1,4 +1,5 @@
 use core::fmt;
+use core::hash;
 use std::marker::PhantomData;
 use std::ops;
 use std::str::FromStr;
@@ -9,16 +10,16 @@ use serde::de::Visitor;
 use serde::ser::SerializeSeq;
 
 #[doc(hidden)]
-#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 pub struct Hex;
-#[derive(Clone, Copy, Debug, Hash, PartialEq, Eq)]
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
 #[doc(hidden)]
 pub struct Array;
 
 /// An object ID that can serialized as a hex-string or an array of integers.
 ///
 /// This only exists because knotserver uses both representations.
-#[derive(Clone, Hash, Eq)]
+#[derive(Clone, Eq)]
 pub struct ObjectId<E = Hex> {
     inner: gix_hash::ObjectId,
     enc: PhantomData<E>,
@@ -49,6 +50,12 @@ impl<E> Default for ObjectId<E> {
     }
 }
 
+impl<E> hash::Hash for ObjectId<E> {
+    fn hash<H: hash::Hasher>(&self, state: &mut H) {
+        self.inner.hash(state);
+    }
+}
+
 impl<E, F> PartialEq<ObjectId<E>> for ObjectId<F> {
     fn eq(&self, other: &ObjectId<E>) -> bool {
         self.inner.eq(&other.inner)
@@ -129,7 +136,7 @@ impl<E> FromStr for ObjectId<E> {
 }
 
 impl<'de> Visitor<'de> for Hex {
-    type Value = ObjectId<Hex>;
+    type Value = ObjectId<Self>;
 
     fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
         formatter.write_str("commit hash")
@@ -154,7 +161,7 @@ impl<'de> Deserialize<'de> for ObjectId<Hex> {
 }
 
 impl<'de> Visitor<'de> for Array {
-    type Value = ObjectId<Array>;
+    type Value = ObjectId<Self>;
 
     fn expecting(&self, formatter: &mut std::fmt::Formatter) -> std::fmt::Result {
         formatter.write_str("commit hash")
diff --git a/crates/gordian-lexicon/src/sh_tangled/knot.rs b/crates/gordian-lexicon/src/sh_tangled/knot.rs
index 6500081..6113462 100644
--- a/crates/gordian-lexicon/src/sh_tangled/knot.rs
+++ b/crates/gordian-lexicon/src/sh_tangled/knot.rs
@@ -47,6 +47,7 @@ pub struct Member<'a> {
 }
 
 impl<'a> Member<'a> {
+    #[must_use]
     pub fn new(subject: &'a Did, domain: &'a str, created_at: OffsetDateTime) -> Self {
         Self {
             subject: subject.into(),