diff --git a/.github/workflows/rust.yml b/.github/workflows/rust.yml
index 5d565fb07..c0eccff9a 100644
--- a/.github/workflows/rust.yml
+++ b/.github/workflows/rust.yml
@@ -19,10 +19,14 @@ jobs:
     timeout-minutes: 15
 
     steps:
-    - run: rustup component add clippy rustfmt
+
     - uses: actions/checkout@v4
-    - name: Rust Cache
-      uses: Swatinem/rust-cache@v2.7.3
+    - uses: actions-rust-lang/setup-rust-toolchain@v1
+      with:
+        components: rustfmt, clippy
+        toolchain: 1.84.0
+    # - name: Rust Cache
+    #   uses: Swatinem/rust-cache@v2.7.3
     - name: Check format
       run: cargo fmt --all -- --check
     - name: Check
diff --git a/crates/ott-balancer/src/balancer.rs b/crates/ott-balancer/src/balancer.rs
index 4c251b0af..6ed3eaf47 100644
--- a/crates/ott-balancer/src/balancer.rs
+++ b/crates/ott-balancer/src/balancer.rs
@@ -414,12 +414,12 @@ impl BalancerContext {
 
     pub fn select_monolith(&self, room: &RoomName) -> anyhow::Result<&BalancerMonolith> {
         let filtered = self.filter_monoliths();
-        return self.monolith_selection.select_monolith(room, filtered);
+        self.monolith_selection.select_monolith(room, filtered)
     }
 
     pub fn random_monolith(&self) -> anyhow::Result<&BalancerMonolith> {
         let filtered = self.filter_monoliths();
-        return self.monolith_selection.random_monolith(filtered);
+        self.monolith_selection.random_monolith(filtered)
     }
 
     #[instrument(skip(self, monolith), err, fields(monolith_id = %monolith))]
diff --git a/crates/ott-balancer/src/client.rs b/crates/ott-balancer/src/client.rs
index 0837e8922..475dd463d 100644
--- a/crates/ott-balancer/src/client.rs
+++ b/crates/ott-balancer/src/client.rs
@@ -346,10 +346,7 @@ pub async fn client_entry<'r>(
     Ok(())
 }
 
-async fn close<'s, S>(
-    stream: &mut WebSocketStream<S>,
-    frame: CloseFrame<'static>,
-) -> anyhow::Result<()>
+async fn close<S>(stream: &mut WebSocketStream<S>, frame: CloseFrame<'static>) -> anyhow::Result<()>
 where
     S: AsyncRead + AsyncWrite + Unpin,
 {
diff --git a/crates/ott-balancer/src/config.rs b/crates/ott-balancer/src/config.rs
index cca95fdb4..cfb618d64 100644
--- a/crates/ott-balancer/src/config.rs
+++ b/crates/ott-balancer/src/config.rs
@@ -48,6 +48,7 @@ impl BalancerConfig {
             config.region = region.into();
         }
         // SAFETY: CONFIG is only mutated once, and only from this thread. All other accesses are read-only.
+        #[allow(static_mut_refs)]
         CONFIG_INIT.call_once(|| unsafe { *CONFIG.borrow_mut() = Some(config) });
         Ok(())
     }
@@ -55,13 +56,17 @@ impl BalancerConfig {
     /// Initialize the config with default values.
     pub fn init_default() {
         // SAFETY: CONFIG is only mutated once, and only from this thread. All other accesses are read-only.
+        #[allow(static_mut_refs)]
         CONFIG_INIT.call_once(|| unsafe { *CONFIG.borrow_mut() = Some(BalancerConfig::default()) });
     }
 
     pub fn get() -> &'static Self {
         debug_assert!(CONFIG_INIT.is_completed(), "config not initialized");
         // SAFETY: get is never called before CONFIG is initialized.
-        unsafe { CONFIG.as_ref().expect("config not initialized") }
+        #[allow(static_mut_refs)]
+        unsafe {
+            CONFIG.as_ref().expect("config not initialized")
+        }
     }
 
     /// Get a mutable reference to the config. Should only be used for tests and benchmarks.
@@ -72,6 +77,7 @@ impl BalancerConfig {
     pub unsafe fn get_mut() -> &'static mut Self {
         debug_assert!(CONFIG_INIT.is_completed(), "config not initialized");
         // SAFETY: get_mut is only used for benchmarks
+        #[allow(static_mut_refs)]
         CONFIG.as_mut().expect("config not initialized")
     }
 }
diff --git a/crates/ott-balancer/src/selection.rs b/crates/ott-balancer/src/selection.rs
index db21a9632..f3cb82758 100644
--- a/crates/ott-balancer/src/selection.rs
+++ b/crates/ott-balancer/src/selection.rs
@@ -13,12 +13,12 @@ pub trait MonolithSelection: std::fmt::Debug {
         &'a self,
         room: &RoomName,
         monoliths: Vec<&'a BalancerMonolith>,
-    ) -> anyhow::Result<&BalancerMonolith>;
+    ) -> anyhow::Result<&'a BalancerMonolith>;
 
     fn random_monolith<'a>(
         &'a self,
         monoliths: Vec<&'a BalancerMonolith>,
-    ) -> anyhow::Result<&BalancerMonolith> {
+    ) -> anyhow::Result<&'a BalancerMonolith> {
         let selected = monoliths
             .iter()
             .choose(&mut rand::thread_rng())
@@ -72,7 +72,7 @@ impl MonolithSelection for MinRoomsSelector {
         &'a self,
         _room: &RoomName,
         monoliths: Vec<&'a BalancerMonolith>,
-    ) -> anyhow::Result<&BalancerMonolith> {
+    ) -> anyhow::Result<&'a BalancerMonolith> {
         fn cmp(x: &BalancerMonolith, y: &BalancerMonolith) -> std::cmp::Ordering {
             x.rooms().len().cmp(&y.rooms().len())
         }
@@ -113,7 +113,7 @@ impl MonolithSelection for HashRingSelector {
         &'a self,
         room: &RoomName,
         monoliths: Vec<&'a BalancerMonolith>,
-    ) -> anyhow::Result<&BalancerMonolith> {
+    ) -> anyhow::Result<&'a BalancerMonolith> {
         let weight = self.config.weight.max(1);
         let mut ring = HashRing::new();
         ring.batch_add(
@@ -154,7 +154,7 @@ impl MonolithSelection for RandomSelector {
         &'a self,
         _room: &RoomName,
         monoliths: Vec<&'a BalancerMonolith>,
-    ) -> anyhow::Result<&BalancerMonolith> {
+    ) -> anyhow::Result<&'a BalancerMonolith> {
         self.random_monolith(monoliths)
     }
 }