diff --git a/src/circuit.rs b/src/circuit.rs
index f65fa4c1..a44581f5 100644
--- a/src/circuit.rs
+++ b/src/circuit.rs
@@ -274,7 +274,7 @@ where
                 let index = self.current_round - sparse_offset - 1;
                 let sparse_matrix = &self.constants.sparse_matrixes[index];
 
-                self.product_mds_with_sparse_matrix::<CS>(&sparse_matrix)?;
+                self.product_mds_with_sparse_matrix::<CS>(sparse_matrix)?;
             } else {
                 self.product_mds_m::<CS>()?;
             }
diff --git a/src/matrix.rs b/src/matrix.rs
index 4062900b..4043f757 100644
--- a/src/matrix.rs
+++ b/src/matrix.rs
@@ -70,7 +70,7 @@ pub fn mat_mul<F: PrimeField>(a: &Matrix<F>, b: &Matrix<F>) -> Option<Matrix<F>>
         .iter()
         .map(|input_row| {
             b_t.iter()
-                .map(|transposed_column| vec_mul(&input_row, &transposed_column))
+                .map(|transposed_column| vec_mul(input_row, transposed_column))
                 .collect()
         })
         .collect();
@@ -251,7 +251,7 @@ fn eliminate<F: PrimeField>(
             let mut factor = val;
             factor.mul_assign(&inv_pivot);
 
-            let scaled_pivot = scalar_vec_mul(factor, &pivot);
+            let scaled_pivot = scalar_vec_mul(factor, pivot);
             let eliminated = vec_sub(row, &scaled_pivot);
             result.push(eliminated);
 
@@ -271,7 +271,7 @@ fn eliminate<F: PrimeField>(
 // `matrix` must be square.
 fn upper_triangular<F: PrimeField>(
     matrix: &Matrix<F>,
-    mut shadow: &mut Matrix<F>,
+    shadow: &mut Matrix<F>,
 ) -> Option<Matrix<F>> {
     assert!(is_square(matrix));
     let mut result = Vec::with_capacity(matrix.len());
@@ -282,7 +282,7 @@ fn upper_triangular<F: PrimeField>(
     while curr.len() > 1 {
         let initial_rows = curr.len();
 
-        curr = eliminate(&curr, column, &mut shadow)?;
+        curr = eliminate(&curr, column, shadow)?;
         result.push(curr[0].clone());
         shadow_result.push(shadow[0].clone());
         column += 1;
@@ -323,8 +323,8 @@ fn reduce_to_identity<F: PrimeField>(
             inv.unwrap()
         };
 
-        let mut normalized = scalar_vec_mul(inv, &row);
-        let mut shadow_normalized = scalar_vec_mul(inv, &shadow_row);
+        let mut normalized = scalar_vec_mul(inv, row);
+        let mut shadow_normalized = scalar_vec_mul(inv, shadow_row);
 
         for j in 0..i {
             let idx = size - j - 1;
@@ -350,7 +350,7 @@ fn reduce_to_identity<F: PrimeField>(
 //
 pub(crate) fn invert<F: PrimeField>(matrix: &Matrix<F>) -> Option<Matrix<F>> {
     let mut shadow = make_identity(columns(matrix));
-    let ut = upper_triangular(&matrix, &mut shadow);
+    let ut = upper_triangular(matrix, &mut shadow);
 
     ut.and_then(|x| reduce_to_identity(&x, &mut shadow))
         .and(Some(shadow))
diff --git a/src/mds.rs b/src/mds.rs
index 6c49a0fd..04700318 100644
--- a/src/mds.rs
+++ b/src/mds.rs
@@ -64,7 +64,7 @@ impl<F: PrimeField> SparseMatrix<F> {
     }
 
     pub fn is_sparse_matrix(m: &Matrix<F>) -> bool {
-        is_square(&m) && is_identity(&minor(&m, 0, 0))
+        is_square(m) && is_identity(&minor(m, 0, 0))
     }
 
     pub fn size(&self) -> usize {
diff --git a/src/poseidon.rs b/src/poseidon.rs
index 7ac7b70d..fd4bc9ce 100644
--- a/src/poseidon.rs
+++ b/src/poseidon.rs
@@ -315,7 +315,7 @@ where
     /// Panics if the provided slice is bigger than the arity.
     pub fn set_preimage(&mut self, preimage: &[F]) {
         self.reset();
-        self.elements[1..].copy_from_slice(&preimage);
+        self.elements[1..].copy_from_slice(preimage);
         self.pos = self.elements.len();
     }
 
@@ -497,7 +497,7 @@ where
                 let index = self.current_round - sparse_offset - 1;
                 let sparse_matrix = &self.constants.sparse_matrixes[index];
 
-                self.product_mds_with_sparse_matrix(&sparse_matrix);
+                self.product_mds_with_sparse_matrix(sparse_matrix);
             } else {
                 self.product_mds();
             }
@@ -606,7 +606,7 @@ where
     pub fn encrypt(&mut self, key: &[F], plaintext: &[F]) -> Result<(Vec<F>, F), Error> {
         // https://link.springer.com/content/pdf/10.1007%2F978-3-642-28496-0_19.pdf
         let arity = A::to_usize();
-        assert!(key.len() > 0);
+        assert!(!key.is_empty());
 
         self.shared_initialize(key, plaintext.len())?;
 
@@ -625,7 +625,7 @@ where
 
     pub fn decrypt(&mut self, key: &[F], ciphertext: &[F], tag: &F) -> Result<Vec<F>, Error> {
         let arity = A::to_usize();
-        assert!(key.len() > 0);
+        assert!(!key.is_empty());
 
         self.shared_initialize(key, ciphertext.len())?;
         let mut plaintext = Vec::with_capacity(ciphertext.len());
@@ -682,7 +682,7 @@ where
     fn hash(&mut self, preimages: &[GenericArray<Fr, A>]) -> Result<Vec<Fr>, Error> {
         Ok(preimages
             .iter()
-            .map(|preimage| Poseidon::new_with_preimage(&preimage, &self.constants).hash())
+            .map(|preimage| Poseidon::new_with_preimage(preimage, &self.constants).hash())
             .collect())
     }
 
diff --git a/src/preprocessing.rs b/src/preprocessing.rs
index e68b1b67..4dda965f 100644
--- a/src/preprocessing.rs
+++ b/src/preprocessing.rs
@@ -66,7 +66,7 @@ pub(crate) fn compress_round_constants<F: PrimeField>(
             partial_keys.push(inverted[0]);
             inverted[0] = F::zero();
 
-            vec_add(&previous_round_keys, &inverted)
+            vec_add(previous_round_keys, &inverted)
         });
 
     // Everything in here is dev-driven testing.
@@ -95,7 +95,7 @@ pub(crate) fn compress_round_constants<F: PrimeField>(
         inv[0] = F::zero();
 
         // (M^-1(T) - pk) - I
-        let result_key = vec_add(&initial_round_keys, &inv);
+        let result_key = vec_add(initial_round_keys, &inv);
 
         assert_eq!(&result_key, &round_acc, "Acc assumption failed.");
         assert_eq!(pk, partial_keys[0], "Partial-key assumption failed.");
@@ -144,7 +144,7 @@ pub(crate) fn compress_round_constants<F: PrimeField>(
 
         quintic_s_box(&mut p_state[0], None, Some(&pk));
 
-        let preprocessed_result = apply_matrix(&mds_matrix, &p_state);
+        let preprocessed_result = apply_matrix(mds_matrix, &p_state);
 
         assert_eq!(
             plain_result, preprocessed_result,