diff --git a/bindings/nodejs/src/lib.rs b/bindings/nodejs/src/lib.rs
index f535af4..71461b2 100644
--- a/bindings/nodejs/src/lib.rs
+++ b/bindings/nodejs/src/lib.rs
@@ -1,3 +1,5 @@
+#![allow(dead_code)]
+
 extern crate napi_derive;
 
 mod cep;
diff --git a/core/src/cep.rs b/core/src/cep.rs
index d6947e8..98fd8c9 100644
--- a/core/src/cep.rs
+++ b/core/src/cep.rs
@@ -313,8 +313,8 @@ mod tests {
 
     #[test]
     fn is_valid_accepts_valid_formatted() {
-        assert!(is_valid(&cep_sp().to_string()));
-        assert!(is_valid(&cep_rj().to_string()));
+        assert!(is_valid(cep_sp().as_ref()));
+        assert!(is_valid(cep_rj().as_ref()));
     }
 
     #[test]
@@ -349,8 +349,8 @@ mod tests {
 
     #[test]
     fn strict_accepts_valid_formatted() {
-        assert!(is_valid_strict(&cep_sp().to_string()).is_ok());
-        assert!(is_valid_strict(&cep_rj().to_string()).is_ok());
+        assert!(is_valid_strict(cep_sp().as_ref()).is_ok());
+        assert!(is_valid_strict(cep_rj().as_ref()).is_ok());
     }
 
     #[test]
@@ -543,9 +543,7 @@ mod tests {
                 assert_eq!(
                     cep.state(),
                     Some(state),
-                    "CEP {} should map to {:?}",
-                    cep,
-                    state
+                    "CEP {cep} should map to {state:?}"
                 );
             }
         }
diff --git a/core/src/cnpj.rs b/core/src/cnpj.rs
index cd91e2d..57d79d2 100644
--- a/core/src/cnpj.rs
+++ b/core/src/cnpj.rs
@@ -770,7 +770,7 @@ mod tests {
         let result = is_valid("00623904000173");
         // It's valid only if check digits match - let's compute
         if let Some((d1, d2)) = compute_check_digits("006239040001") {
-            let cnpj_str = alloc::format!("006239040001{}{}", d1, d2);
+            let cnpj_str = alloc::format!("006239040001{d1}{d2}");
             assert!(is_valid(&cnpj_str));
             let cnpj: Cnpj = cnpj_str.parse().unwrap();
             assert!(cnpj.as_str().starts_with("00"));
diff --git a/core/src/municipio.rs b/core/src/municipio.rs
index 20d4713..3b521c6 100644
--- a/core/src/municipio.rs
+++ b/core/src/municipio.rs
@@ -27984,9 +27984,7 @@ mod tests {
             assert!(
                 (a.state as u8) < (b.state as u8)
                     || ((a.state as u8) == (b.state as u8) && a.name <= b.name),
-                "{} should come before {}",
-                a,
-                b
+                "{a} should come before {b}"
             );
         }
     }
@@ -27995,7 +27993,7 @@ mod tests {
     fn each_state_has_municipalities() {
         for &state in &crate::uf::ALL {
             let munis = Municipio::by_state(state);
-            assert!(!munis.is_empty(), "{:?} has no municipalities", state);
+            assert!(!munis.is_empty(), "{state:?} has no municipalities");
         }
     }
 
@@ -28004,8 +28002,7 @@ mod tests {
         for &code in &CAPITAL_CODES {
             assert!(
                 Municipio::from_ibge_code(code).is_some(),
-                "Capital code {} not found",
-                code
+                "Capital code {code} not found"
             );
         }
     }
@@ -28021,7 +28018,7 @@ mod tests {
 
     #[test]
     fn from_ibge_code_sao_paulo() {
-        let sp = Municipio::from_ibge_code(3550308).unwrap();
+        let sp = Municipio::from_ibge_code(3_550_308).unwrap();
         assert_eq!(sp.name, "São Paulo");
         assert_eq!(sp.state, State::SP);
     }
@@ -28029,7 +28026,7 @@ mod tests {
     #[test]
     fn from_ibge_code_returns_none() {
         assert!(Municipio::from_ibge_code(0).is_none());
-        assert!(Municipio::from_ibge_code(9999999).is_none());
+        assert!(Municipio::from_ibge_code(9_999_999).is_none());
     }
 
     #[test]
@@ -28050,18 +28047,18 @@ mod tests {
 
     #[test]
     fn is_capital_correct() {
-        let sp = Municipio::from_ibge_code(3550308).unwrap();
+        let sp = Municipio::from_ibge_code(3_550_308).unwrap();
         assert!(sp.is_capital());
 
         // Campinas is not a capital
-        let campinas = Municipio::from_ibge_code(3509502).unwrap();
+        let campinas = Municipio::from_ibge_code(3_509_502).unwrap();
         assert!(!campinas.is_capital());
     }
 
     #[test]
     fn display_format() {
         use alloc::string::ToString;
-        let sp = Municipio::from_ibge_code(3550308).unwrap();
+        let sp = Municipio::from_ibge_code(3_550_308).unwrap();
         assert_eq!(sp.to_string(), "São Paulo/SP");
     }
 
diff --git a/core/tests/parity.rs b/core/tests/parity.rs
index e2658a5..e187bbf 100644
--- a/core/tests/parity.rs
+++ b/core/tests/parity.rs
@@ -8,10 +8,10 @@ use std::collections::HashMap;
 use stdbr_core::{cep, cnpj, cpf, municipio, uf};
 
 fn golden() -> Value {
-    let path = std::env::var("GOLDEN_JSON")
-        .unwrap_or_else(|_| "tests/parity/golden.json".to_string());
-    let json = std::fs::read_to_string(&path)
-        .unwrap_or_else(|e| panic!("failed to read {path}: {e}"));
+    let path =
+        std::env::var("GOLDEN_JSON").unwrap_or_else(|_| "tests/parity/golden.json".to_string());
+    let json =
+        std::fs::read_to_string(&path).unwrap_or_else(|e| panic!("failed to read {path}: {e}"));
     serde_json::from_str(&json).expect("failed to parse golden.json")
 }