diff --git a/shellfirm/build.rs b/shellfirm/build.rs
index 9678474..62445e5 100644
--- a/shellfirm/build.rs
+++ b/shellfirm/build.rs
@@ -9,7 +9,7 @@ fn main() -> Result<()> {
 
     let dest_checks_path = Path::new(&out_dir).join("all-checks.yaml");
     let dest_groups = Path::new(&out_dir).join("all_the_files.rs");
-    let mut groups_names = File::create(&dest_groups)?;
+    let mut groups_names = File::create(dest_groups)?;
 
     writeln!(&mut groups_names, r##"["##,)?;
 
@@ -26,7 +26,7 @@ fn main() -> Result<()> {
             .unwrap()
             .to_str()
             .expect("could not get file name");
-        writeln!(&mut groups_names, r##""{name}","##, name = file_name)?;
+        writeln!(&mut groups_names, r##""{file_name}","##)?;
     }
 
     writeln!(&mut groups_names, r##"]"##,)?;
diff --git a/shellfirm/src/bin/cmd/config.rs b/shellfirm/src/bin/cmd/config.rs
index dbb67e5..654e242 100644
--- a/shellfirm/src/bin/cmd/config.rs
+++ b/shellfirm/src/bin/cmd/config.rs
@@ -64,7 +64,7 @@ pub fn run_update_groups(
         }),
         Err(e) => Ok(shellfirm::CmdExit {
             code: exitcode::CONFIG,
-            message: Some(format!("Could not update checks group. error: {}", e)),
+            message: Some(format!("Could not update checks group. error: {e}")),
         }),
     }
 }
@@ -77,7 +77,7 @@ pub fn run_reset(config: &Config, force_selection: Option<usize>) -> shellfirm::
         },
         Err(e) => shellfirm::CmdExit {
             code: exitcode::CONFIG,
-            message: Some(format!("reset settings error: {:?}", e)),
+            message: Some(format!("reset settings error: {e:?}")),
         },
     }
 }
@@ -97,7 +97,7 @@ pub fn run_challenge(config: &Config, challenge: Option<Challenge>) -> Result<sh
         }),
         Err(e) => Ok(shellfirm::CmdExit {
             code: exitcode::CONFIG,
-            message: Some(format!("change challenge error: {:?}", e)),
+            message: Some(format!("change challenge error: {e:?}")),
         }),
     }
 }
@@ -131,7 +131,7 @@ pub fn run_ignore(
         }),
         Err(e) => Ok(shellfirm::CmdExit {
             code: exitcode::CONFIG,
-            message: Some(format!("update pattern ignore errors: {:?}", e)),
+            message: Some(format!("update pattern ignore errors: {e:?}")),
         }),
     }
 }
@@ -165,7 +165,7 @@ pub fn run_deny(
         }),
         Err(e) => Ok(shellfirm::CmdExit {
             code: exitcode::CONFIG,
-            message: Some(format!("update pattern ignore errors: {:?}", e)),
+            message: Some(format!("update pattern ignore errors: {e:?}")),
         }),
     }
 }
diff --git a/shellfirm/src/bin/shellfirm.rs b/shellfirm/src/bin/shellfirm.rs
index b96f6cc..59a4091 100644
--- a/shellfirm/src/bin/shellfirm.rs
+++ b/shellfirm/src/bin/shellfirm.rs
@@ -24,7 +24,7 @@ fn main() {
     let config = match Config::new(None) {
         Ok(config) => config,
         Err(err) => {
-            eprintln!("Loading config error: {}", err);
+            eprintln!("Loading config error: {err}");
             exit(1)
         }
     };
@@ -51,7 +51,7 @@ fn main() {
     let checks = match settings.get_active_checks() {
         Ok(c) => c,
         Err(e) => {
-            eprintln!("Could not load checks. err: Error: {}", e);
+            eprintln!("Could not load checks. err: Error: {e}");
             exit(1)
         }
     };
diff --git a/shellfirm/src/checks.rs b/shellfirm/src/checks.rs
index 867b6c8..3890384 100644
--- a/shellfirm/src/checks.rs
+++ b/shellfirm/src/checks.rs
@@ -83,7 +83,7 @@ pub fn challenge(
     }
 
     for description in descriptions {
-        eprintln!("* {}", description);
+        eprintln!("* {description}");
     }
     eprintln!();
 
diff --git a/shellfirm/src/config.rs b/shellfirm/src/config.rs
index 6b0a66d..74ecf6c 100644
--- a/shellfirm/src/config.rs
+++ b/shellfirm/src/config.rs
@@ -55,7 +55,7 @@ pub struct Settings {
 }
 
 impl fmt::Display for Challenge {
-    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         match self {
             Self::Math => write!(f, "Math"),
             Self::Enter => write!(f, "Enter"),
@@ -103,7 +103,7 @@ impl Config {
                     // compatibility if the folder $HOME/.shellfirm exists, shillfirm
                     // continue work with that folder. If the folder does not exists, the default
                     // use config dir
-                    let homedir = p.join(format!(".{}", package_name));
+                    let homedir = p.join(format!(".{package_name}"));
                     let conf_dir = dirs::config_dir().unwrap_or_else(|| homedir.clone());
                     if homedir.is_dir() {
                         homedir
diff --git a/shellfirm/src/prompt.rs b/shellfirm/src/prompt.rs
index 8dd6c83..1cf09e9 100644
--- a/shellfirm/src/prompt.rs
+++ b/shellfirm/src/prompt.rs
@@ -40,7 +40,7 @@ pub fn math_challenge() -> bool {
         if answer == expected_answer {
             break;
         }
-        eprintln!("{}", WRONG_ANSWER);
+        eprintln!("{WRONG_ANSWER}");
     }
     true
 }
@@ -53,7 +53,7 @@ pub fn enter_challenge() -> bool {
         if answer == "\n" {
             break;
         }
-        eprintln!("{}", WRONG_ANSWER);
+        eprintln!("{WRONG_ANSWER}");
     }
     true
 }
@@ -65,7 +65,7 @@ pub fn yes_challenge() -> bool {
         if show_stdin_prompt().trim() == "yes" {
             break;
         }
-        eprintln!("{}", WRONG_ANSWER);
+        eprintln!("{WRONG_ANSWER}");
     }
     true
 }