diff --git a/.github/actions/artifact_failure/action.yml b/.github/actions/artifact_failure/action.yml
index 071fe0917..cf77bee2a 100644
--- a/.github/actions/artifact_failure/action.yml
+++ b/.github/actions/artifact_failure/action.yml
@@ -23,7 +23,7 @@ runs:
             --exclude='bins' \
             --exclude='.git' \
             -zcf target/failure-${{ inputs.name }}.tar.gz .
-    - uses: actions/upload-artifact@v3
+    - uses: actions/upload-artifact@v4
       with:
         name: ${{ inputs.name }}
         path: target/failure-${{ inputs.name }}.tar.gz
diff --git a/src/bin/sccache-dist/build.rs b/src/bin/sccache-dist/build.rs
index 33f9f6d3c..3f8088be4 100644
--- a/src/bin/sccache-dist/build.rs
+++ b/src/bin/sccache-dist/build.rs
@@ -511,7 +511,7 @@ impl DockerBuilder {
             .context("Unable to list all Docker containers")?;
         if !containers.is_empty() {
             let mut containers_to_rm = vec![];
-            for line in containers.split(|c| c == '\n') {
+            for line in containers.split('\n') {
                 let mut iter = line.splitn(2, ' ');
                 let container_id = iter
                     .next()
@@ -541,7 +541,7 @@ impl DockerBuilder {
             .context("Failed to list all docker images")?;
         if !images.is_empty() {
             let mut images_to_rm = vec![];
-            for line in images.split(|c| c == '\n') {
+            for line in images.split('\n') {
                 let mut iter = line.splitn(2, ' ');
                 let image_id = iter
                     .next()
@@ -609,7 +609,7 @@ impl DockerBuilder {
         let diff = docker_diff(cid)?;
         if !diff.is_empty() {
             let mut lastpath = None;
-            for line in diff.split(|c| c == '\n') {
+            for line in diff.split('\n') {
                 let mut iter = line.splitn(2, ' ');
                 let changetype = iter
                     .next()
diff --git a/src/bin/sccache-dist/main.rs b/src/bin/sccache-dist/main.rs
index 89e28e4bb..28c4a1dc8 100644
--- a/src/bin/sccache-dist/main.rs
+++ b/src/bin/sccache-dist/main.rs
@@ -85,7 +85,7 @@ fn create_server_token(server_id: ServerId, auth_token: &str) -> String {
     format!("{} {}", server_id.addr(), auth_token)
 }
 fn check_server_token(server_token: &str, auth_token: &str) -> Option<ServerId> {
-    let mut split = server_token.splitn(2, |c| c == ' ');
+    let mut split = server_token.splitn(2, ' ');
     let server_addr = split.next().and_then(|addr| addr.parse().ok())?;
     match split.next() {
         Some(t) if t == auth_token => Some(ServerId::new(server_addr)),
diff --git a/src/compiler/args.rs b/src/compiler/args.rs
index 64d7eb98a..739a026ae 100644
--- a/src/compiler/args.rs
+++ b/src/compiler/args.rs
@@ -167,7 +167,7 @@ pub struct Iter<'a, T> {
     emitted: usize,
 }
 
-impl<'a, T: ArgumentValue> Iterator for Iter<'a, T> {
+impl<T: ArgumentValue> Iterator for Iter<'_, T> {
     type Item = OsString;
 
     fn next(&mut self) -> Option<Self::Item> {
@@ -218,7 +218,7 @@ pub struct IterStrings<'a, T, F> {
 }
 
 #[cfg(feature = "dist-client")]
-impl<'a, T: ArgumentValue, F: FnMut(&Path) -> Option<String>> Iterator for IterStrings<'a, T, F> {
+impl<T: ArgumentValue, F: FnMut(&Path) -> Option<String>> Iterator for IterStrings<'_, T, F> {
     type Item = ArgToStringResult;
 
     fn next(&mut self) -> Option<Self::Item> {
diff --git a/src/compiler/c.rs b/src/compiler/c.rs
index 726e91b88..9207e8d1a 100644
--- a/src/compiler/c.rs
+++ b/src/compiler/c.rs
@@ -286,7 +286,7 @@ where
             .ok()
             .map(|f| {
                 f.flatten()
-                    .filter(|f| f.path().extension().map_or(false, |ext| ext == "bc"))
+                    .filter(|f| f.path().extension().is_some_and(|ext| ext == "bc"))
                     .map(|f| f.path())
                     .collect()
             })
@@ -1263,7 +1263,7 @@ impl pkg::InputsPackager for CInputsPackager {
             if !super::CAN_DIST_DYLIBS
                 && input_path
                     .extension()
-                    .map_or(false, |ext| ext == std::env::consts::DLL_EXTENSION)
+                    .is_some_and(|ext| ext == std::env::consts::DLL_EXTENSION)
             {
                 bail!(
                     "Cannot distribute dylib input {} on this platform",
diff --git a/src/compiler/diab.rs b/src/compiler/diab.rs
index 60291b87f..6f16c526d 100644
--- a/src/compiler/diab.rs
+++ b/src/compiler/diab.rs
@@ -399,7 +399,7 @@ impl<'a> ExpandAtArgs<'a> {
     }
 }
 
-impl<'a> Iterator for ExpandAtArgs<'a> {
+impl Iterator for ExpandAtArgs<'_> {
     type Item = OsString;
 
     fn next(&mut self) -> Option<OsString> {
diff --git a/src/compiler/gcc.rs b/src/compiler/gcc.rs
index 9f43ea255..aefd7cd54 100644
--- a/src/compiler/gcc.rs
+++ b/src/compiler/gcc.rs
@@ -969,15 +969,12 @@ impl<'a> ExpandIncludeFile<'a> {
     }
 }
 
-impl<'a> Iterator for ExpandIncludeFile<'a> {
+impl Iterator for ExpandIncludeFile<'_> {
     type Item = OsString;
 
     fn next(&mut self) -> Option<OsString> {
         loop {
-            let arg = match self.stack.pop() {
-                Some(arg) => arg,
-                None => return None,
-            };
+            let arg = self.stack.pop()?;
             let file = match arg.split_prefix("@") {
                 Some(arg) => self.cwd.join(arg),
                 None => return Some(arg),
diff --git a/src/compiler/msvc.rs b/src/compiler/msvc.rs
index 19eae82a1..fcfe66bdb 100644
--- a/src/compiler/msvc.rs
+++ b/src/compiler/msvc.rs
@@ -1184,7 +1184,7 @@ impl<'a> ExpandIncludeFile<'a> {
     }
 }
 
-impl<'a> Iterator for ExpandIncludeFile<'a> {
+impl Iterator for ExpandIncludeFile<'_> {
     type Item = OsString;
 
     fn next(&mut self) -> Option<OsString> {
@@ -1197,10 +1197,7 @@ impl<'a> Iterator for ExpandIncludeFile<'a> {
             }
 
             // Visit the next argument provided by the original command iterator.
-            let arg = match self.args.pop() {
-                Some(arg) => arg,
-                None => return None,
-            };
+            let arg = self.args.pop()?;
             let file_arg = match arg.split_prefix("@") {
                 Some(file_arg) => file_arg,
                 None => return Some(arg),
@@ -1290,7 +1287,7 @@ where
     }
 }
 
-impl<'a> SplitMsvcResponseFileArgs<'a> {
+impl SplitMsvcResponseFileArgs<'_> {
     /// Appends backslashes to `target` by decrementing `count`.
     /// If `step` is >1, then `count` is decremented by `step`, resulting in 1 backslash appended for every `step`.
     fn append_backslashes_to(target: &mut String, count: &mut usize, step: usize) {
@@ -1301,7 +1298,7 @@ impl<'a> SplitMsvcResponseFileArgs<'a> {
     }
 }
 
-impl<'a> Iterator for SplitMsvcResponseFileArgs<'a> {
+impl Iterator for SplitMsvcResponseFileArgs<'_> {
     type Item = String;
 
     fn next(&mut self) -> Option<String> {
diff --git a/src/config.rs b/src/config.rs
index 68dfe3cd4..4dce460e4 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -579,7 +579,7 @@ pub fn try_read_config_file<T: DeserializeOwned>(path: &Path) -> Result<Option<T
         }
     }
 
-    let res = if path.extension().map_or(false, |e| e == "json") {
+    let res = if path.extension().is_some_and(|e| e == "json") {
         serde_json::from_str(&string)
             .with_context(|| format!("Failed to load json config file from {}", path.display()))?
     } else {
diff --git a/src/dist/http.rs b/src/dist/http.rs
index 3ee6bc667..caa29608b 100644
--- a/src/dist/http.rs
+++ b/src/dist/http.rs
@@ -532,7 +532,7 @@ mod server {
     fn bearer_http_auth(request: &rouille::Request) -> Option<&str> {
         let header = request.header("Authorization")?;
 
-        let mut split = header.splitn(2, |c| c == ' ');
+        let mut split = header.splitn(2, ' ');
 
         let authtype = split.next()?;
         if authtype != "Bearer" {
diff --git a/src/dist/mod.rs b/src/dist/mod.rs
index a55b7c1e3..0aca86232 100644
--- a/src/dist/mod.rs
+++ b/src/dist/mod.rs
@@ -621,14 +621,14 @@ pub struct BuildResult {
 // structs
 
 pub struct ToolchainReader<'a>(Box<dyn Read + 'a>);
-impl<'a> Read for ToolchainReader<'a> {
+impl Read for ToolchainReader<'_> {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.0.read(buf)
     }
 }
 
 pub struct InputsReader<'a>(Box<dyn Read + Send + 'a>);
-impl<'a> Read for InputsReader<'a> {
+impl Read for InputsReader<'_> {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.0.read(buf)
     }
diff --git a/src/lru_disk_cache/lru_cache.rs b/src/lru_disk_cache/lru_cache.rs
index f4bf3d8f2..031530d4e 100644
--- a/src/lru_disk_cache/lru_cache.rs
+++ b/src/lru_disk_cache/lru_cache.rs
@@ -643,7 +643,7 @@ impl<'a, K, V> DoubleEndedIterator for Iter<'a, K, V> {
     }
 }
 
-impl<'a, K, V> ExactSizeIterator for Iter<'a, K, V> {
+impl<K, V> ExactSizeIterator for Iter<'_, K, V> {
     fn len(&self) -> usize {
         self.0.len()
     }
@@ -671,7 +671,7 @@ impl<'a, K, V> DoubleEndedIterator for IterMut<'a, K, V> {
     }
 }
 
-impl<'a, K, V> ExactSizeIterator for IterMut<'a, K, V> {
+impl<K, V> ExactSizeIterator for IterMut<'_, K, V> {
     fn len(&self) -> usize {
         self.0.len()
     }
diff --git a/src/util.rs b/src/util.rs
index 7174681d6..fd928732e 100644
--- a/src/util.rs
+++ b/src/util.rs
@@ -829,7 +829,7 @@ pub struct HashToDigest<'a> {
     pub digest: &'a mut Digest,
 }
 
-impl<'a> Hasher for HashToDigest<'a> {
+impl Hasher for HashToDigest<'_> {
     fn write(&mut self, bytes: &[u8]) {
         self.digest.update(bytes)
     }
diff --git a/tests/harness/mod.rs b/tests/harness/mod.rs
index c1c209dc0..6504ea308 100644
--- a/tests/harness/mod.rs
+++ b/tests/harness/mod.rs
@@ -69,7 +69,7 @@ pub fn stop_local_daemon() -> bool {
         .stdout(Stdio::null())
         .stderr(Stdio::null())
         .status()
-        .map_or(false, |status| status.success())
+        .is_ok_and(|status| status.success())
 }
 
 pub fn get_stats<F: 'static + Fn(ServerInfo)>(f: F) {
diff --git a/tests/helpers/mod.rs b/tests/helpers/mod.rs
index 3fc36bf10..a9cbc6cf1 100644
--- a/tests/helpers/mod.rs
+++ b/tests/helpers/mod.rs
@@ -1,3 +1,5 @@
+#![allow(clippy::result_large_err)]
+
 use anyhow::{Context, Result};
 use assert_cmd::assert::OutputAssertExt;
 use chrono::Local;