diff --git a/cli/tests/test_git_import_export.rs b/cli/tests/test_git_import_export.rs
index d28bb2c03..fc537d14f 100644
--- a/cli/tests/test_git_import_export.rs
+++ b/cli/tests/test_git_import_export.rs
@@ -15,7 +15,6 @@ use std::path::Path;
 
 use itertools::Itertools as _;
 use jj_lib::backend::CommitId;
-use jj_lib::object_id::ObjectId as _;
 
 use crate::common::TestEnvironment;
 
diff --git a/lib/src/default_revset_engine.rs b/lib/src/default_revset_engine.rs
index fd4265b1b..8c69881e8 100644
--- a/lib/src/default_revset_engine.rs
+++ b/lib/src/default_revset_engine.rs
@@ -1001,7 +1001,6 @@ mod tests {
     use super::*;
     use crate::backend::{ChangeId, CommitId};
     use crate::default_index::DefaultMutableIndex;
-    use crate::object_id::ObjectId;
 
     /// Generator of unique 16-byte ChangeId excluding root id
     fn change_id_generator() -> impl FnMut() -> ChangeId {
diff --git a/lib/src/id_prefix.rs b/lib/src/id_prefix.rs
index 1d599602a..e0fe7daa1 100644
--- a/lib/src/id_prefix.rs
+++ b/lib/src/id_prefix.rs
@@ -446,7 +446,6 @@ fn unwrap_as_short_key<const N: usize>(key_bytes: &[u8]) -> &[u8; N] {
 mod tests {
     use super::*;
     use crate::backend::ChangeId;
-    use crate::object_id::ObjectId;
 
     #[derive(Clone, Copy, Eq, PartialEq)]
     struct Position(usize);
diff --git a/lib/src/object_id.rs b/lib/src/object_id.rs
index 9c43f2dc3..734599ef2 100644
--- a/lib/src/object_id.rs
+++ b/lib/src/object_id.rs
@@ -15,12 +15,9 @@
 #![allow(missing_docs)]
 
 pub trait ObjectId {
-    fn new(value: Vec<u8>) -> Self;
     fn object_type(&self) -> String;
-    fn from_bytes(bytes: &[u8]) -> Self;
     fn as_bytes(&self) -> &[u8];
     fn to_bytes(&self) -> Vec<u8>;
-    fn from_hex(hex: &str) -> Self;
     fn hex(&self) -> String;
 }
 
@@ -36,6 +33,20 @@ macro_rules! id_type {
 
 macro_rules! impl_id_type {
     ($name:ident) => {
+        impl $name {
+            pub fn new(value: Vec<u8>) -> Self {
+                Self(value)
+            }
+
+            pub fn from_bytes(bytes: &[u8]) -> Self {
+                Self(bytes.to_vec())
+            }
+
+            pub fn from_hex(hex: &str) -> Self {
+                Self(hex::decode(hex).unwrap())
+            }
+        }
+
         impl std::fmt::Debug for $name {
             fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> Result<(), std::fmt::Error> {
                 f.debug_tuple(stringify!($name)).field(&self.hex()).finish()
@@ -43,10 +54,6 @@ macro_rules! impl_id_type {
         }
 
         impl crate::object_id::ObjectId for $name {
-            fn new(value: Vec<u8>) -> Self {
-                Self(value)
-            }
-
             fn object_type(&self) -> String {
                 stringify!($name)
                     .strip_suffix("Id")
@@ -55,10 +62,6 @@ macro_rules! impl_id_type {
                     .to_string()
             }
 
-            fn from_bytes(bytes: &[u8]) -> Self {
-                Self(bytes.to_vec())
-            }
-
             fn as_bytes(&self) -> &[u8] {
                 &self.0
             }
@@ -67,10 +70,6 @@ macro_rules! impl_id_type {
                 self.0.clone()
             }
 
-            fn from_hex(hex: &str) -> Self {
-                Self(hex::decode(hex).unwrap())
-            }
-
             fn hex(&self) -> String {
                 hex::encode(&self.0)
             }
diff --git a/lib/src/op_walk.rs b/lib/src/op_walk.rs
index 6fab77cd0..adae474f0 100644
--- a/lib/src/op_walk.rs
+++ b/lib/src/op_walk.rs
@@ -22,7 +22,7 @@ use std::sync::Arc;
 use itertools::Itertools as _;
 use thiserror::Error;
 
-use crate::object_id::{HexPrefix, ObjectId as _};
+use crate::object_id::HexPrefix;
 use crate::op_heads_store::{OpHeadResolutionError, OpHeadsStore};
 use crate::op_store::{OpStore, OpStoreError, OpStoreResult, OperationId};
 use crate::operation::Operation;
diff --git a/lib/src/refs.rs b/lib/src/refs.rs
index 56514312f..14751efa2 100644
--- a/lib/src/refs.rs
+++ b/lib/src/refs.rs
@@ -205,7 +205,6 @@ pub fn classify_branch_push_action(targets: TrackingRefPair) -> BranchPushAction
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::object_id::ObjectId;
     use crate::op_store::RemoteRefState;
 
     fn new_remote_ref(target: RefTarget) -> RemoteRef {
diff --git a/lib/src/settings.rs b/lib/src/settings.rs
index 22b41c271..be51e237c 100644
--- a/lib/src/settings.rs
+++ b/lib/src/settings.rs
@@ -24,7 +24,6 @@ use rand_chacha::ChaCha20Rng;
 use crate::backend::{ChangeId, Commit, Signature, Timestamp};
 use crate::fmt_util::binary_prefix;
 use crate::fsmonitor::FsmonitorKind;
-use crate::object_id::ObjectId;
 use crate::signing::SignBehavior;
 
 #[derive(Debug, Clone)]
diff --git a/lib/tests/test_commit_builder.rs b/lib/tests/test_commit_builder.rs
index eb6bc38f7..976069a36 100644
--- a/lib/tests/test_commit_builder.rs
+++ b/lib/tests/test_commit_builder.rs
@@ -15,7 +15,6 @@
 use jj_lib::backend::{ChangeId, MillisSinceEpoch, Signature, Timestamp};
 use jj_lib::matchers::EverythingMatcher;
 use jj_lib::merged_tree::DiffSummary;
-use jj_lib::object_id::ObjectId;
 use jj_lib::repo::Repo;
 use jj_lib::repo_path::{RepoPath, RepoPathBuf};
 use jj_lib::settings::UserSettings;
diff --git a/lib/tests/test_local_working_copy.rs b/lib/tests/test_local_working_copy.rs
index 8445ea458..85134612b 100644
--- a/lib/tests/test_local_working_copy.rs
+++ b/lib/tests/test_local_working_copy.rs
@@ -31,7 +31,6 @@ use jj_lib::fsmonitor::FsmonitorKind;
 use jj_lib::local_working_copy::LocalWorkingCopy;
 use jj_lib::merge::Merge;
 use jj_lib::merged_tree::MergedTreeBuilder;
-use jj_lib::object_id::ObjectId;
 use jj_lib::op_store::{OperationId, WorkspaceId};
 use jj_lib::repo::{ReadonlyRepo, Repo};
 use jj_lib::repo_path::{RepoPath, RepoPathBuf, RepoPathComponent};