diff --git a/src/encoder_advanced.hpp b/src/encoder_advanced.hpp
index 389f706..7f10c22 100644
--- a/src/encoder_advanced.hpp
+++ b/src/encoder_advanced.hpp
@@ -18,39 +18,25 @@
 
 #include "autogen_ldpc_QC.hpp"
 
-void noise_bitstring_inplace(auto &src, double err_prob, unsigned int seed = 0) {
-    std::mt19937_64 rng{seed}; // hard-coded seed for testing purposes.
 
-    std::bernoulli_distribution distribution(err_prob);
-
-    for (std::size_t i = 0; i < src.size(); i++) {
-        if (distribution(rng)) {
-            src[i] = !src[i];
-        } else {
-            src[i] = src[i];
+namespace LDPC4QKD {
+    template<std::size_t N>
+    constexpr auto bits_needed() {
+        auto n = N;
+        std::size_t number_of_bits{0ul};
+        while (n > 0) {
+            n >>= 1;
+            number_of_bits++;
         }
+        return number_of_bits;
     }
-}
-
-template<std::size_t N>
-constexpr auto bits_needed() {
-    auto n = N;
-    std::size_t number_of_bits{0ul};
-    while (n > 0) {
-        n >>= 1;
-        number_of_bits++;
-    }
-    return number_of_bits;
-}
 
-template<std::size_t N>
-using smallest_type = std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint8_t), std::uint8_t,
-        std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint16_t), std::uint16_t,
-                std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint32_t), std::uint32_t, std::uint64_t>>>;
+    template<std::size_t N>
+    using smallest_type = std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint8_t), std::uint8_t,
+            std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint16_t), std::uint16_t,
+                    std::conditional_t<bits_needed<N>() <= 8 * sizeof(std::uint32_t), std::uint32_t, std::uint64_t>>>;
 
 
-namespace LDPC4QKD {
-
     template<typename Bit1, typename Bit2>
     constexpr bool xor_as_bools(Bit1 lhs, Bit2 rhs) {
         return (static_cast<bool>(lhs) != static_cast<bool>(rhs));
diff --git a/tests/test_encoder_advanced.cpp b/tests/test_encoder_advanced.cpp
index e4401f5..10cd9f8 100644
--- a/tests/test_encoder_advanced.cpp
+++ b/tests/test_encoder_advanced.cpp
@@ -14,6 +14,22 @@
 
 using namespace LDPC4QKD;
 
+namespace {
+    void noise_bitstring_inplace(auto &src, double err_prob, unsigned int seed = 0) {
+        std::mt19937_64 rng{seed}; // hard-coded seed for testing purposes.
+
+        std::bernoulli_distribution distribution(err_prob);
+
+        for (std::size_t i = 0; i < src.size(); i++) {
+            if (distribution(rng)) {
+                src[i] = !src[i];
+            } else {
+                src[i] = src[i];
+            }
+        }
+    }
+}
+
 TEST(test_encoder_advanced, basic_example) {
     std::cout << "hello\n";
     unsigned seed = 42; // seed for PRNG
@@ -40,7 +56,7 @@ TEST(test_encoder_advanced, basic_example) {
         // Use the non-generic version of `encode_with`:
         std::cout << "Syndrome of runtime known size " << syndrome_vec.size() << std::endl;
         for (auto v: syndrome_vec) {
-            std::cout << static_cast<int>(v)  << ' ';  // print syndrome bits
+            std::cout << static_cast<int>(v) << ' ';  // print syndrome bits
         }
         std::cout << std::endl;
     }