diff --git a/src/time.rs b/src/time.rs
index 13f3b78..4be1607 100644
--- a/src/time.rs
+++ b/src/time.rs
@@ -14,16 +14,11 @@ pub trait Clock {
 }
 
 pub enum Realtime {}
-pub enum Monotonic {}
 
 impl Clock for Realtime {
     const ID: ClockId = ClockId::Realtime;
 }
 
-impl Clock for Monotonic {
-    const ID: ClockId = ClockId::Monotonic;
-}
-
 pub struct ClockSample<C> {
     time_s: u64,
     time_ns: u64,
@@ -56,10 +51,6 @@ impl<C: Clock> ClockSample<C> {
     pub fn as_secs_f64(&self) -> f64 {
         self.time_s as f64 + self.time_ns as f64 / 1_000_000_000.0
     }
-
-    pub fn to_milliseconds(&self) -> u64 {
-        (self.time_s * 1000) + (self.time_ns / 1000000)
-    }
 }
 
 impl ClockSample<Realtime> {
diff --git a/src/util.rs b/src/util.rs
index d7d1855..31c988c 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -3,20 +3,10 @@
 // SPDX-License-Identifier: MPL-2.0
 
 use anyhow::anyhow;
-use std::sync::{Arc, Mutex, MutexGuard, RwLock, RwLockReadGuard, RwLockWriteGuard};
+use std::sync::{Arc, RwLock, RwLockReadGuard, RwLockWriteGuard};
 
 pub type ArcRwLock<T> = Arc<RwLock<T>>;
 
-pub trait MutexExt<T> {
-    fn lock_anyhow(&self) -> anyhow::Result<MutexGuard<'_, T>>;
-}
-
-impl<T> MutexExt<T> for Mutex<T> {
-    fn lock_anyhow(&self) -> anyhow::Result<MutexGuard<'_, T>> {
-        self.lock().map_err(|e| anyhow!("mutex poisoned: {e}"))
-    }
-}
-
 pub trait RwLockExt<T> {
     fn read_anyhow(&self) -> anyhow::Result<RwLockReadGuard<'_, T>>;
     fn write_anyhow(&self) -> anyhow::Result<RwLockWriteGuard<'_, T>>;