diff --git a/backend/common/src/dense_map.rs b/backend/common/src/dense_map.rs
index 3dfd420..d529eb1 100644
--- a/backend/common/src/dense_map.rs
+++ b/backend/common/src/dense_map.rs
@@ -139,8 +139,7 @@ mod test {
 
     #[test]
     fn len_doesnt_panic_if_lots_of_retired() {
-
-        let mut map = DenseMap::<usize,usize>::new();
+        let mut map = DenseMap::<usize, usize>::new();
 
         let id1 = map.add(1);
         let id2 = map.add(2);
@@ -163,5 +162,4 @@ mod test {
 
         assert_eq!(map.len(), 0);
     }
-
-}
\ No newline at end of file
+}
diff --git a/backend/common/src/ws_client/sender.rs b/backend/common/src/ws_client/sender.rs
index 9cb8ee7..b81529c 100644
--- a/backend/common/src/ws_client/sender.rs
+++ b/backend/common/src/ws_client/sender.rs
@@ -60,7 +60,9 @@ impl Sender {
         Ok(())
     }
     /// Convert this sender into a Sink
-    pub fn into_sink(self) -> impl futures::Sink<SentMessage> + std::marker::Unpin + Clone + 'static {
+    pub fn into_sink(
+        self,
+    ) -> impl futures::Sink<SentMessage> + std::marker::Unpin + Clone + 'static {
         self.inner.into_sink()
     }
 }
diff --git a/backend/telemetry_core/src/aggregator/aggregator.rs b/backend/telemetry_core/src/aggregator/aggregator.rs
index 8ba8cc2..d6604a8 100644
--- a/backend/telemetry_core/src/aggregator/aggregator.rs
+++ b/backend/telemetry_core/src/aggregator/aggregator.rs
@@ -62,11 +62,12 @@ impl Aggregator {
         let (tx_to_aggregator, rx_from_external) = flume::unbounded();
 
         // Kick off a locator task to locate nodes, which hands back a channel to make location requests
-        let tx_to_locator = find_location(tx_to_aggregator.clone().into_sink().with(|(node_id, msg)| {
-            future::ok::<_, flume::SendError<_>>(inner_loop::ToAggregator::FromFindLocation(
-                node_id, msg,
-            ))
-        }));
+        let tx_to_locator =
+            find_location(tx_to_aggregator.clone().into_sink().with(|(node_id, msg)| {
+                future::ok::<_, flume::SendError<_>>(inner_loop::ToAggregator::FromFindLocation(
+                    node_id, msg,
+                ))
+            }));
 
         // Handle any incoming messages in our handler loop:
         tokio::spawn(Aggregator::handle_messages(
diff --git a/backend/telemetry_core/src/aggregator/aggregator_set.rs b/backend/telemetry_core/src/aggregator/aggregator_set.rs
index 8fb6251..7dd368d 100644
--- a/backend/telemetry_core/src/aggregator/aggregator_set.rs
+++ b/backend/telemetry_core/src/aggregator/aggregator_set.rs
@@ -2,9 +2,9 @@ use super::aggregator::{Aggregator, AggregatorOpts};
 use super::inner_loop;
 use common::EitherSink;
 use futures::{Sink, SinkExt};
-use inner_loop::{ Metrics, FromShardWebsocket };
+use inner_loop::{FromShardWebsocket, Metrics};
 use std::sync::atomic::{AtomicUsize, Ordering};
-use std::sync::{ Arc, Mutex };
+use std::sync::{Arc, Mutex};
 
 #[derive(Clone)]
 pub struct AggregatorSet(Arc<AggregatorSetInner>);
@@ -12,7 +12,7 @@ pub struct AggregatorSet(Arc<AggregatorSetInner>);
 pub struct AggregatorSetInner {
     aggregators: Vec<Aggregator>,
     next_idx: AtomicUsize,
-    metrics: Mutex<Vec<Metrics>>
+    metrics: Mutex<Vec<Metrics>>,
 }
 
 impl AggregatorSet {
@@ -28,14 +28,12 @@ impl AggregatorSet {
         )
         .await?;
 
-        let initial_metrics = (0..num_aggregators)
-            .map(|_| Metrics::default())
-            .collect();
+        let initial_metrics = (0..num_aggregators).map(|_| Metrics::default()).collect();
 
         let this = AggregatorSet(Arc::new(AggregatorSetInner {
             aggregators,
             next_idx: AtomicUsize::new(0),
-            metrics: Mutex::new(initial_metrics)
+            metrics: Mutex::new(initial_metrics),
         }));
 
         // Start asking for metrics:
@@ -60,14 +58,16 @@ impl AggregatorSet {
                         // loop has failed completely.
                         Err(e) => {
                             log::error!("Error obtaining metrics (bailing): {}", e);
-                            return
+                            return;
                         }
                     };
 
                     // Lock, update the stored metrics and drop the lock immediately.
                     // We discard any error; if somethign went wrong talking to the inner loop,
                     // it's probably a fatal error
-                    { inner.metrics.lock().unwrap()[idx] = metrics; }
+                    {
+                        inner.metrics.lock().unwrap()[idx] = metrics;
+                    }
 
                     // Sleep *at least* 10 seconds. If it takes a while to get metrics back, we'll
                     // end up waiting longer between requests.
diff --git a/backend/telemetry_core/src/aggregator/inner_loop.rs b/backend/telemetry_core/src/aggregator/inner_loop.rs
index 72e468b..20ed612 100644
--- a/backend/telemetry_core/src/aggregator/inner_loop.rs
+++ b/backend/telemetry_core/src/aggregator/inner_loop.rs
@@ -102,7 +102,7 @@ pub enum FromFeedWebsocket {
 }
 
 /// A set of metrics returned when we ask for metrics
-#[derive(Clone,Debug,Default)]
+#[derive(Clone, Debug, Default)]
 pub struct Metrics {
     /// When in unix MS from epoch were these metrics obtained
     pub timestamp_unix_ms: u64,
@@ -122,7 +122,7 @@ pub struct Metrics {
     /// How many feeds are currently connected to this aggregator.
     pub connected_feeds: usize,
     /// How many shards are currently connected to this aggregator.
-    pub connected_shards: usize
+    pub connected_shards: usize,
 }
 
 // The frontend sends text based commands; parse them into these messages:
@@ -220,7 +220,7 @@ impl InnerLoop {
                     }
                     ToAggregator::FromFindLocation(node_id, location) => {
                         self.handle_from_find_location(node_id, location)
-                    },
+                    }
                     ToAggregator::GatherMetrics(tx) => {
                         self.handle_gather_metrics(tx, metered_rx.len())
                     }
@@ -249,8 +249,11 @@ impl InnerLoop {
     }
 
     /// Gather and return some metrics.
-    fn handle_gather_metrics(&mut self, rx: flume::Sender<Metrics>, total_messages_to_aggregator: usize) {
-
+    fn handle_gather_metrics(
+        &mut self,
+        rx: flume::Sender<Metrics>,
+        total_messages_to_aggregator: usize,
+    ) {
         let timestamp_unix_ms = time::now();
         let connected_nodes = self.node_ids.len();
         let subscribed_feeds = self.feed_conn_id_to_chain.len();
@@ -258,10 +261,7 @@ impl InnerLoop {
         let subscribed_finality_feeds = self.feed_conn_id_finality.len();
         let connected_shards = self.shard_channels.len();
         let connected_feeds = self.feed_channels.len();
-        let total_messages_to_feeds: usize = self.feed_channels
-            .values()
-            .map(|c| c.len())
-            .sum();
+        let total_messages_to_feeds: usize = self.feed_channels.values().map(|c| c.len()).sum();
 
         // Ignore error sending; assume the receiver stopped caring and dropped the channel:
         let _ = rx.send(Metrics {
@@ -273,7 +273,7 @@ impl InnerLoop {
             total_messages_to_aggregator,
             connected_nodes,
             connected_feeds,
-            connected_shards
+            connected_shards,
         });
     }
 
diff --git a/backend/telemetry_core/src/main.rs b/backend/telemetry_core/src/main.rs
index 0e2c61b..91308b0 100644
--- a/backend/telemetry_core/src/main.rs
+++ b/backend/telemetry_core/src/main.rs
@@ -178,11 +178,9 @@ async fn start_server(num_aggregators: usize, opts: Opts) -> anyhow::Result<()>
                             let _ = ws_send.close().await;
                         },
                     ))
-                },
+                }
                 // Return metrics in a prometheus-friendly text based format:
-                (&Method::GET, "/metrics") => {
-                    Ok(return_prometheus_metrics(aggregator).await)
-                },
+                (&Method::GET, "/metrics") => Ok(return_prometheus_metrics(aggregator).await),
                 // 404 for anything else:
                 _ => Ok(Response::builder()
                     .status(404)
@@ -496,14 +494,38 @@ async fn return_prometheus_metrics(aggregator: AggregatorSet) -> Response<hyper:
     // be handled correctly when pointing a current version of prometheus at it.
     let mut s = String::new();
     for (idx, m) in metrics.iter().enumerate() {
-        s.push_str(&format!("telemetry_connected_feeds{{aggregator=\"{}\"}} {} {}\n", idx, m.connected_feeds, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_connected_nodes{{aggregator=\"{}\"}} {} {}\n", idx, m.connected_nodes, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_connected_shards{{aggregator=\"{}\"}} {} {}\n", idx, m.connected_shards, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_chains_subscribed_to{{aggregator=\"{}\"}} {} {}\n", idx, m.chains_subscribed_to, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_subscribed_feeds{{aggregator=\"{}\"}} {} {}\n", idx, m.subscribed_feeds, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_subscribed_finality_feeds{{aggregator=\"{}\"}} {} {}\n", idx, m.subscribed_finality_feeds, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_total_messages_to_feeds{{aggregator=\"{}\"}} {} {}\n", idx, m.total_messages_to_feeds, m.timestamp_unix_ms));
-        s.push_str(&format!("telemetry_total_messages_to_aggregator{{aggregator=\"{}\"}} {} {}\n\n", idx, m.total_messages_to_aggregator, m.timestamp_unix_ms));
+        s.push_str(&format!(
+            "telemetry_connected_feeds{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.connected_feeds, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_connected_nodes{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.connected_nodes, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_connected_shards{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.connected_shards, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_chains_subscribed_to{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.chains_subscribed_to, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_subscribed_feeds{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.subscribed_feeds, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_subscribed_finality_feeds{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.subscribed_finality_feeds, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_total_messages_to_feeds{{aggregator=\"{}\"}} {} {}\n",
+            idx, m.total_messages_to_feeds, m.timestamp_unix_ms
+        ));
+        s.push_str(&format!(
+            "telemetry_total_messages_to_aggregator{{aggregator=\"{}\"}} {} {}\n\n",
+            idx, m.total_messages_to_aggregator, m.timestamp_unix_ms
+        ));
     }
 
     Response::builder()
@@ -511,4 +533,4 @@ async fn return_prometheus_metrics(aggregator: AggregatorSet) -> Response<hyper:
         .header(http::header::CONTENT_TYPE, "text/plain; version=0.0.4")
         .body(s.into())
         .unwrap()
-}
\ No newline at end of file
+}
diff --git a/backend/telemetry_core/tests/soak_tests.rs b/backend/telemetry_core/tests/soak_tests.rs
index da7e93b..d033a74 100644
--- a/backend/telemetry_core/tests/soak_tests.rs
+++ b/backend/telemetry_core/tests/soak_tests.rs
@@ -242,7 +242,7 @@ struct SoakTestOpts {
     log_output: bool,
     /// How many worker threads should the soak test runner use?
     #[structopt(long, default_value = "4")]
-    test_worker_threads: usize
+    test_worker_threads: usize,
 }
 
 /// Get soak test args from an envvar and parse them via structopt.
diff --git a/backend/test_utils/src/server/channels.rs b/backend/test_utils/src/server/channels.rs
index 4ca9274..047de88 100644
--- a/backend/test_utils/src/server/channels.rs
+++ b/backend/test_utils/src/server/channels.rs
@@ -42,7 +42,10 @@ impl ShardSender {
         self.unbounded_send(ws_client::SentMessage::Binary(bytes))
     }
     /// Send JSON as a textual websocket message
-    pub fn send_json_text(&mut self, json: serde_json::Value) -> Result<(), flume::SendError<ws_client::SentMessage>> {
+    pub fn send_json_text(
+        &mut self,
+        json: serde_json::Value,
+    ) -> Result<(), flume::SendError<ws_client::SentMessage>> {
         let s = serde_json::to_string(&json).expect("valid string");
         self.unbounded_send(ws_client::SentMessage::Text(s))
     }