diff --git a/src/crate_metadata.rs b/src/crate_metadata.rs
index 9b47b7d190f1e4e2461b757c7fe4c03ea5d053ab..9f081564b9fbe2b22d9d7ab43dd6142c37d6fb9e 100644
--- a/src/crate_metadata.rs
+++ b/src/crate_metadata.rs
@@ -46,14 +46,14 @@ impl CrateMetadata {
         let mut target_directory = metadata.target_directory.as_path().join("ink");
 
         // Normalize the package and lib name.
-        let package_name = root_package.name.replace("-", "_");
+        let package_name = root_package.name.replace('-', "_");
         let lib_name = &root_package
             .targets
             .iter()
             .find(|target| target.kind.iter().any(|t| t == "cdylib"))
             .expect("lib name not found")
             .name
-            .replace("-", "_");
+            .replace('-', "_");
 
         let absolute_manifest_path = manifest_path.absolute_directory()?;
         let absolute_workspace_root = metadata.workspace_root.canonicalize()?;
diff --git a/src/main.rs b/src/main.rs
index beb5d09ec3483e187502482124a0a95f6a6fe771..98db48ebea605ca41fa5b288178ce4e45faf3b81 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -139,7 +139,7 @@ impl std::str::FromStr for OptimizationPasses {
         // We need to replace " here, since the input string could come
         // from either the CLI or the `Cargo.toml` profile section.
         // If it is from the profile it could e.g. be "3" or 3.
-        let normalized_input = input.replace("\"", "").to_lowercase();
+        let normalized_input = input.replace('"', "").to_lowercase();
         match normalized_input.as_str() {
             "0" => Ok(OptimizationPasses::Zero),
             "1" => Ok(OptimizationPasses::One),