diff --git a/command-parser/benches/commands.rs b/command-parser/benches/commands.rs
index c61d526355c..de9aee94fff 100644
--- a/command-parser/benches/commands.rs
+++ b/command-parser/benches/commands.rs
@@ -3,6 +3,7 @@ use patricia_tree::PatriciaSet;
 use std::{
     borrow::Cow,
     collections::{BTreeSet, HashSet},
+    iter::FromIterator,
 };
 
 fn btreeset(set: &BTreeSet<Cow<'static, str>>, needle: &str) {
@@ -77,7 +78,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     ];
 
     c.bench_function("c: btreeset", |b| {
-        let mut set = BTreeSet::from_iter(commands.iter().map(Cow::from));
+        let set = BTreeSet::from_iter(commands.iter().map(|e| Cow::from(*e)));
 
         b.iter(|| {
             for command in commands.iter() {
@@ -87,11 +88,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
 
     c.bench_function("c: hashset", |b| {
-        let mut set = HashSet::from_iter(commands.iter().map(Cow::from));
-
-        for e in commands.iter() {
-            set.insert(Cow::from(*e));
-        }
+        let set = HashSet::from_iter(commands.iter().map(|e| Cow::from(*e)));
 
         b.iter(|| {
             for command in commands.iter() {
@@ -111,7 +108,7 @@ fn criterion_benchmark(c: &mut Criterion) {
     });
 
     c.bench_function("c: patricia_tree", |b| {
-        let mut set = PatriciaSet::from_iter(commands.iter());
+        let set = PatriciaSet::from_iter(commands.iter());
 
         b.iter(|| {
             for command in commands.iter() {
diff --git a/model/benches/deserialization.rs b/model/benches/deserialization.rs
index 01c3d33fc6d..ea89b6be423 100644
--- a/model/benches/deserialization.rs
+++ b/model/benches/deserialization.rs
@@ -151,7 +151,7 @@ fn reaction() {
             }
         },
         "message_id": "3",
-        "user_id": "4",
+        "user_id": "4"
     }"#;
 
     serde_json::from_str::<Reaction>(input).unwrap();
@@ -184,11 +184,11 @@ fn typing_start() {
 
 fn criterion_benchmark(c: &mut Criterion) {
     c.bench_function("gateway event role delete", |b| {
-        b.iter(gateway_event_role_delete())
+        b.iter(gateway_event_role_delete)
     });
-    c.bench_function("member chunk", |b| b.iter(member_chunk()));
-    c.bench_function("reaction", |b| b.iter(reaction()));
-    c.bench_function("typing start", |b| b.iter(typing_start()));
+    c.bench_function("member chunk", |b| b.iter(member_chunk));
+    c.bench_function("reaction", |b| b.iter(reaction));
+    c.bench_function("typing start", |b| b.iter(typing_start));
 }
 
 criterion_group!(benches, criterion_benchmark);