diff --git a/aes/src/lib.rs b/aes/src/lib.rs
index e12bf30..fabc0e8 100644
--- a/aes/src/lib.rs
+++ b/aes/src/lib.rs
@@ -4,6 +4,5 @@ mod constants;
 mod key;
 mod operations;
 mod sbox;
-mod utils;
 
 pub use {aes::Aes, block::Block128};
diff --git a/aes/src/utils.rs b/aes/src/utils.rs
deleted file mode 100644
index b23c23b..0000000
--- a/aes/src/utils.rs
+++ /dev/null
@@ -1,28 +0,0 @@
-/// Generic bit permutation for DES specification.
-/// DES uses 1-based positioning where bit 1 is the leftmost (MSB) and bit 64 is the rightmost (LSB).
-/// This function handles this correctly for arbitrary input/output sizes.
-///
-/// # Arguments
-/// - `input` - The input value (treated as a bitfield of `input_bits` size)
-/// - `input_bits` - Number of meaningful bits in the input (1-64)
-/// - `output_bits` - Number of bits in the output (1-64)
-/// - `position_table` - Table of 1-based positions (1 to `input_bits`) where each output bit comes from.
-///   The table should have `output_bits` entries. For each entry i (0-based), `position_table`[i] indicates
-///   which input bit (1-based) should go to the i-th output bit position (from MSB to LSB).
-#[must_use]
-pub fn _permutate(
-    input: u64,
-    input_bit_amount: u64,
-    output_bit_amount: u64,
-    position_table: &[u8],
-) -> u64 {
-    position_table
-        .iter()
-        .enumerate()
-        .fold(0, |acc, (idx, &input_pos_1based)| {
-            let input_bit_pos = input_bit_amount - u64::from(input_pos_1based);
-            let bit_value = (input >> input_bit_pos) & 1;
-            let output_bit_pos = output_bit_amount - 1 - (idx as u64);
-            acc | (bit_value << output_bit_pos)
-        })
-}