diff --git a/Chaos/Cipher/Block/Decryptor.hpp b/Chaos/Cipher/Block/Decryptor.hpp
index e27c130..bd38cf2 100644
--- a/Chaos/Cipher/Block/Decryptor.hpp
+++ b/Chaos/Cipher/Block/Decryptor.hpp
@@ -1,44 +1,32 @@
 #ifndef CHAOS_CIPHER_BLOCK_DECRYPTOR_HPP
 #define CHAOS_CIPHER_BLOCK_DECRYPTOR_HPP
 
+#include <concepts>
+#include <cstdint>
+#include <type_traits>
+
 namespace Chaos::Cipher::Block
 {
 
 template<typename T>
-class Decryptor
+concept Decryptor = requires(const T constDecryptor,
+                             typename T::Block block,
+                             uint8_t * outBegin, uint8_t * outEnd,
+                             uint8_t * inBegin, uint8_t * inEnd)
 {
-public:
-    template<typename OutputIt, typename InputIt>
-    void DecryptBlock(OutputIt outBegin, OutputIt outEnd,
-                      InputIt inBegin, InputIt inEnd) const
-    {
-        Impl().DecryptBlock(outBegin, outEnd, inBegin, inEnd);
-    }
+    typename T::Block;
+    typename T::Key;
+    requires std::constructible_from<T, typename T::Key>;
 
-    template<typename Block>
-    auto DecryptBlock(Block block) const
-    {
-        return Impl().DecryptBlock(block);
-    }
+    requires std::unsigned_integral<std::remove_cvref_t<decltype(T::BlockSize)>>;
+    typename std::integral_constant<decltype(T::BlockSize), T::BlockSize>;
 
-    auto GetBlockSize() const
-    {
-        return Impl().GetBlockSize();
-    }
+    requires std::unsigned_integral<std::remove_cvref_t<decltype(T::KeySize)>>;
+    typename std::integral_constant<decltype(T::KeySize), T::KeySize>;
 
-protected:
-    Decryptor() = default;
-
-private:
-    const T & Impl() const
-    {
-        return static_cast<const T &>(*this);
-    }
-
-    T & Impl()
-    {
-        return static_cast<T &>(*this);
-    }
+    constDecryptor.DecryptBlock(outBegin, outEnd, inBegin, inEnd);
+    { constDecryptor.DecryptBlock(block) } -> std::same_as<typename T::Block>;
+    { constDecryptor.GetBlockSize() } -> std::unsigned_integral;
 };
 
 } // namespace Chaos::Cipher::Block
diff --git a/Chaos/Cipher/Block/Des/DesCrypt.hpp b/Chaos/Cipher/Block/Des/DesCrypt.hpp
index f303c50..de6119f 100644
--- a/Chaos/Cipher/Block/Des/DesCrypt.hpp
+++ b/Chaos/Cipher/Block/Des/DesCrypt.hpp
@@ -233,9 +233,10 @@ public:
         Inner_::RawKey Key_;
     };
 
-    class Encryptor : public Chaos::Cipher::Block::Encryptor<Encryptor>
+    class Encryptor
     {
     public:
+        using Block = DesCrypt::Block;
         using Key = DesCrypt::Key;
         static constexpr size_t BlockSize = DesCrypt::BlockSize;
         static constexpr size_t KeySize = DesCrypt::KeySize;
@@ -278,9 +279,12 @@ public:
         Inner_::KeySchedule Schedule_;
     };
 
-    class Decryptor : public Chaos::Cipher::Block::Decryptor<Decryptor>
+    static_assert(Chaos::Cipher::Block::Encryptor<Encryptor>);
+
+    class Decryptor
     {
     public:
+        using Block = DesCrypt::Block;
         using Key = DesCrypt::Key;
         static constexpr size_t BlockSize = DesCrypt::BlockSize;
         static constexpr size_t KeySize = DesCrypt::KeySize;
@@ -323,6 +327,8 @@ public:
         Inner_::KeySchedule Schedule_;
     };
 
+    static_assert(Chaos::Cipher::Block::Decryptor<Decryptor>);
+
 private:
     using BlockHalf = uint32_t;
     using RawBlockArray = Service::SeArray<uint8_t, 8>;
diff --git a/Chaos/Cipher/Block/Encryptor.hpp b/Chaos/Cipher/Block/Encryptor.hpp
index ba3f9f5..ddd3cf3 100644
--- a/Chaos/Cipher/Block/Encryptor.hpp
+++ b/Chaos/Cipher/Block/Encryptor.hpp
@@ -1,44 +1,32 @@
 #ifndef CHAOS_CIPHER_BLOCK_ENCRYPTOR_HPP
 #define CHAOS_CIPHER_BLOCK_ENCRYPTOR_HPP
 
+#include <concepts>
+#include <cstdint>
+#include <type_traits>
+
 namespace Chaos::Cipher::Block
 {
 
 template<typename T>
-class Encryptor
+concept Encryptor = requires(const T constEncryptor,
+                             typename T::Block block,
+                             uint8_t * outBegin, uint8_t * outEnd,
+                             uint8_t * inBegin, uint8_t * inEnd)
 {
-public:
-    template<typename OutputIt, typename InputIt>
-    void EncryptBlock(OutputIt outBegin, OutputIt outEnd,
-                      InputIt inBegin, InputIt inEnd) const
-    {
-        Impl().EncryptBlock(outBegin, outEnd, inBegin, inEnd);
-    }
+    typename T::Block;
+    typename T::Key;
+    requires std::constructible_from<T, typename T::Key>;
 
-    template<typename Block>
-    auto EncryptBlock(Block block) const
-    {
-        return Impl().EncryptBlock(block);
-    }
+    requires std::unsigned_integral<std::remove_cvref_t<decltype(T::BlockSize)>>;
+    typename std::integral_constant<decltype(T::BlockSize), T::BlockSize>;
 
-    auto GetBlockSize() const
-    {
-        return Impl().GetBlockSize();
-    }
+    requires std::unsigned_integral<std::remove_cvref_t<decltype(T::KeySize)>>;
+    typename std::integral_constant<decltype(T::KeySize), T::KeySize>;
 
-protected:
-    Encryptor() = default;
-
-private:
-    const T & Impl() const
-    {
-        return static_cast<const T &>(*this);
-    }
-
-    T & Impl()
-    {
-        return static_cast<T &>(*this);
-    }
+    constEncryptor.EncryptBlock(outBegin, outEnd, inBegin, inEnd);
+    { constEncryptor.EncryptBlock(block) } -> std::same_as<typename T::Block>;
+    { constEncryptor.GetBlockSize() } -> std::unsigned_integral;
 };
 
 } // namespace Chaos::Cipher::Block
diff --git a/Chaos/Hash/Hash.hpp b/Chaos/Hash/Hash.hpp
index fe252e1..ea73799 100644
--- a/Chaos/Hash/Hash.hpp
+++ b/Chaos/Hash/Hash.hpp
@@ -1,38 +1,17 @@
 #ifndef CHAOS_HASH_HASH_HPP
 #define CHAOS_HASH_HASH_HPP
 
+#include <concepts>
 #include <string>
 
 namespace Chaos::Hash
 {
 
 template<typename T>
-class Hash
+concept Hash = requires(const T constHash)
 {
-public:
-    auto GetRawDigest() const
-    {
-        return Impl().GetRawDigest();
-    }
-
-    std::string ToHexString() const
-    {
-        return Impl().ToHexString();
-    }
-
-protected:
-    Hash() = default;
-
-private:
-    const T & Impl() const
-    {
-        return static_cast<const T &>(*this);
-    }
-
-    T & Impl()
-    {
-        return static_cast<T &>(*this);
-    }
+    constHash.GetRawDigest();
+    { constHash.ToHexString() } -> std::same_as<std::string>;
 };
 
 } // namespace Chaos::Hash
diff --git a/Chaos/Hash/Hasher.hpp b/Chaos/Hash/Hasher.hpp
index 796c02f..7055828 100644
--- a/Chaos/Hash/Hasher.hpp
+++ b/Chaos/Hash/Hasher.hpp
@@ -1,42 +1,26 @@
 #ifndef CHAOS_HASH_HASHER_HPP
 #define CHAOS_HASH_HASHER_HPP
 
+#include <concepts>
+#include <cstdint>
+#include <type_traits>
+
+#include "Hash.hpp"
+
 namespace Chaos::Hash
 {
 
 template<typename T>
-class Hasher
+concept Hasher = requires(T hasher, uint8_t * begin, uint8_t * end)
 {
-public:
-    void Reset()
-    {
-        Impl().Reset();
-    }
+    typename T::HashType;
 
-    template<typename InputIt>
-    void Update(InputIt begin, InputIt end)
-    {
-        Impl().Update(begin, end);
-    }
+    requires std::unsigned_integral<std::remove_cvref_t<decltype(T::BLOCK_SIZE_BYTES)>>;
+    typename std::integral_constant<decltype(T::BLOCK_SIZE_BYTES), T::BLOCK_SIZE_BYTES>;
 
-    auto Finish()
-    {
-        return Impl().Finish();
-    }
-
-protected:
-    Hasher() = default;
-
-private:
-    const T & Impl() const
-    {
-        return static_cast<const T &>(*this);
-    }
-
-    T & Impl()
-    {
-        return static_cast<T &>(*this);
-    }
+    hasher.Reset();
+    hasher.Update(begin, end);
+    { hasher.Finish() } -> Hash;
 };
 
 } // namespace Chaos::Hash
diff --git a/Chaos/Hash/Md4.hpp b/Chaos/Hash/Md4.hpp
index 103bd3e..e78dec3 100644
--- a/Chaos/Hash/Md4.hpp
+++ b/Chaos/Hash/Md4.hpp
@@ -136,7 +136,7 @@ private:
 namespace Chaos::Hash::Md4
 {
 
-struct Md4Hash : public Hash<Md4Hash>
+struct Md4Hash
 {
     std::array<uint8_t, 16> GetRawDigest() const
     {
@@ -161,7 +161,9 @@ struct Md4Hash : public Hash<Md4Hash>
     std::array<uint8_t, 16> RawDigest_;
 };
 
-class Md4Hasher : public Hasher<Md4Hasher>
+static_assert(Hash<Md4Hash>);
+
+class Md4Hasher
 {
 public:
     using HashType = Md4Hash;
@@ -302,6 +304,8 @@ private:
     }
 };
 
+static_assert(Hasher<Md4Hasher>);
+
 } // namespace Chaos::Hash::Md4
 
 #endif // CHAOS_HASH_MD4_HPP
diff --git a/Chaos/Hash/Md5.hpp b/Chaos/Hash/Md5.hpp
index 7e6c97a..cb1be91 100644
--- a/Chaos/Hash/Md5.hpp
+++ b/Chaos/Hash/Md5.hpp
@@ -160,7 +160,7 @@ private:
 namespace Chaos::Hash::Md5
 {
 
-struct Md5Hash : public Hash<Md5Hash>
+struct Md5Hash
 {
     std::array<uint8_t, 16> GetRawDigest() const
     {
@@ -185,7 +185,9 @@ struct Md5Hash : public Hash<Md5Hash>
     std::array<uint8_t, 16> RawDigest_;
 };
 
-class Md5Hasher : public Hasher<Md5Hasher>
+static_assert(Hash<Md5Hash>);
+
+class Md5Hasher
 {
 public:
     using HashType = Md5Hash;
@@ -326,6 +328,8 @@ private:
     }
 };
 
+static_assert(Hasher<Md5Hasher>);
+
 } // namespace Chaos::Hash::Md5
 
 #endif // CHAOS_HASH_MD5_HPP
diff --git a/Chaos/Hash/Sha1.hpp b/Chaos/Hash/Sha1.hpp
index 877a0d8..ad743d8 100644
--- a/Chaos/Hash/Sha1.hpp
+++ b/Chaos/Hash/Sha1.hpp
@@ -129,7 +129,7 @@ private:
 namespace Chaos::Hash::Sha1
 {
 
-struct Sha1Hash : public Hash<Sha1Hash>
+struct Sha1Hash
 {
     std::array<uint8_t, 20> GetRawDigest() const
     {
@@ -155,7 +155,9 @@ struct Sha1Hash : public Hash<Sha1Hash>
     std::array<uint8_t, 20> RawDigest_;
 };
 
-class Sha1Hasher : public Hasher<Sha1Hasher>
+static_assert(Hash<Sha1Hash>);
+
+class Sha1Hasher
 {
 public:
     using HashType = Sha1Hash;
@@ -296,6 +298,8 @@ private:
     }
 };
 
+static_assert(Hasher<Sha1Hasher>);
+
 } // namespace Chaos::Hash::Sha1
 
 #endif // CHAOS_HASH_SHA1_HPP
diff --git a/Chaos/Mac/Hmac.hpp b/Chaos/Mac/Hmac.hpp
index 125bb3a..82ecc7e 100644
--- a/Chaos/Mac/Hmac.hpp
+++ b/Chaos/Mac/Hmac.hpp
@@ -3,7 +3,6 @@
 
 #include <array>
 #include <cstdint>
-#include <type_traits>
 
 #include "Hash/Hasher.hpp"
 #include "Service/ChaosException.hpp"
@@ -11,8 +10,7 @@
 namespace Chaos::Mac::Hmac
 {
 
-template<typename HasherImpl,
-         typename = std::enable_if_t<std::is_base_of_v<Hash::Hasher<HasherImpl>, HasherImpl>>>
+template<Hash::Hasher HasherImpl>
 class Hmac
 {
 public:
diff --git a/Chaos/Padding/Padder.hpp b/Chaos/Padding/Padder.hpp
index 5ae50e0..1807d5e 100644
--- a/Chaos/Padding/Padder.hpp
+++ b/Chaos/Padding/Padder.hpp
@@ -1,38 +1,16 @@
 #ifndef CHAOS_PADDING_PADDER_HPP
 #define CHAOS_PADDING_PADDER_HPP
 
+#include <cstdint>
+
 namespace Chaos::Padding
 {
 
 template<typename T>
-class Padder
+concept Padder = requires(uint8_t * begin, uint8_t * end)
 {
-public:
-    template<typename OutputIt>
-    void Pad(OutputIt begin, OutputIt end) const
-    {
-        Impl().Pad(begin, end);
-    }
-
-    template<typename InputIt>
-    auto ComputeUnpad(InputIt begin, InputIt end) const noexcept
-    {
-        return Impl().ComputeUnpad(begin, end);
-    }
-
-protected:
-    Padder() = default;
-
-private:
-    const T & Impl() const
-    {
-        return static_cast<const T &>(*this);
-    }
-
-    T & Impl()
-    {
-        return static_cast<T &>(*this);
-    }
+    T::Pad(begin, end);
+    { T::ComputeUnpad(begin, end) } noexcept;
 };
 
 } // namespace Chaos::Padding
diff --git a/Chaos/Padding/PadderIso7816.hpp b/Chaos/Padding/PadderIso7816.hpp
index c5af640..ee21f27 100644
--- a/Chaos/Padding/PadderIso7816.hpp
+++ b/Chaos/Padding/PadderIso7816.hpp
@@ -12,7 +12,7 @@
 namespace Chaos::Padding
 {
 
-class PadderIso7816 : public Padder<PadderIso7816>
+class PadderIso7816
 {
 public:
     template<typename OutputIt>
@@ -82,6 +82,8 @@ private:
     using Branchless = Service::Branchless;
 };
 
+static_assert(Padder<PadderIso7816>);
+
 } // namespace Chaos::Padding
 
 #endif // CHAOS_PADDING_PADDERISO7816_HPP
diff --git a/Chaos/Padding/PadderPkcs7.hpp b/Chaos/Padding/PadderPkcs7.hpp
index 325a01f..61c4a60 100644
--- a/Chaos/Padding/PadderPkcs7.hpp
+++ b/Chaos/Padding/PadderPkcs7.hpp
@@ -13,7 +13,7 @@
 namespace Chaos::Padding
 {
 
-class PadderPkcs7 : public Padder<PadderPkcs7>
+class PadderPkcs7
 {
 public:
     template<typename OutputIt>
@@ -75,6 +75,8 @@ private:
     using Branchless = Service::Branchless;
 };
 
+static_assert(Padder<PadderPkcs7>);
+
 } // namespace Chaos::Padding
 
 #endif // CHAOS_PADDING_PADDERPKCS7_HPP
diff --git a/Chaos/Service/SeArray.hpp b/Chaos/Service/SeArray.hpp
index 24c7875..604cc01 100644
--- a/Chaos/Service/SeArray.hpp
+++ b/Chaos/Service/SeArray.hpp
@@ -2,14 +2,13 @@
 #define CHAOS_SERVICE_SEARRAY_HPP
 
 #include <array>
-#include <type_traits>
+#include <concepts>
 #include <cstddef>
 
 namespace Chaos::Service
 {
 
-template<typename T, size_t S,
-         typename = std::enable_if_t<std::is_integral_v<T>>>
+template<std::integral T, size_t S>
 class SeArray
 {
 public:
diff --git a/ChaosTests/Cipher/Block/Des/DesCryptTests.cpp b/ChaosTests/Cipher/Block/Des/DesCryptTests.cpp
index 417f765..7d9b86b 100644
--- a/ChaosTests/Cipher/Block/Des/DesCryptTests.cpp
+++ b/ChaosTests/Cipher/Block/Des/DesCryptTests.cpp
@@ -486,9 +486,9 @@ TEST(DesCryptTests, OutIteratorUsageDecryptTest)
     }
 }
 
-template<typename Impl, typename InputIt>
-static std::vector<uint8_t> EncryptThroughBase(const Encryptor<Impl> & enc,
-                                               InputIt begin, InputIt end)
+template<Encryptor EncryptorImpl, typename InputIt>
+static std::vector<uint8_t> EncryptGeneric(const EncryptorImpl & enc,
+                                           InputIt begin, InputIt end)
 {
     std::vector<uint8_t> result;
     result.resize(enc.GetBlockSize(), 0);
@@ -497,7 +497,7 @@ static std::vector<uint8_t> EncryptThroughBase(const Encryptor<Impl> & enc,
     return result;
 }
 
-TEST(DesCryptTests, EncryptThroughBaseTest)
+TEST(DesCryptTests, EncryptGenericTest)
 {
     std::array<uint8_t, DesCrypt::KeySize> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
 
@@ -507,16 +507,16 @@ TEST(DesCryptTests, EncryptThroughBaseTest)
     DesCrypt::Key desKey(key.begin(), key.end());
     DesCrypt::Encryptor enc(desKey);
 
-    ASSERT_EQ(expected, EncryptThroughBase(enc, data.begin(), data.end()));
+    ASSERT_EQ(expected, EncryptGeneric(enc, data.begin(), data.end()));
 }
 
-template<typename Impl>
-static uint64_t EncryptUInt64BlockThroughBase(const Encryptor<Impl> & enc, uint64_t block)
+template<Encryptor EncryptorImpl>
+static uint64_t EncryptUInt64BlockGeneric(const EncryptorImpl & enc, uint64_t block)
 {
     return enc.EncryptBlock(block);
 }
 
-TEST(DesCryptTests, EncryptUInt64BlockThroughBaseTest)
+TEST(DesCryptTests, EncryptUInt64BlockGenericTest)
 {
     std::array<uint8_t, DesCrypt::KeySize> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
 
@@ -526,12 +526,12 @@ TEST(DesCryptTests, EncryptUInt64BlockThroughBaseTest)
     DesCrypt::Key desKey(key.begin(), key.end());
     DesCrypt::Encryptor enc(desKey);
 
-    ASSERT_EQ(expected, EncryptUInt64BlockThroughBase(enc, data));
+    ASSERT_EQ(expected, EncryptUInt64BlockGeneric(enc, data));
 }
 
-template<typename Impl, typename InputIt>
-static std::vector<uint8_t> DecryptThroughBase(const Decryptor<Impl> & dec,
-                                               InputIt begin, InputIt end)
+template<Decryptor DecryptorImpl, typename InputIt>
+static std::vector<uint8_t> DecryptGeneric(const DecryptorImpl & dec,
+                                           InputIt begin, InputIt end)
 {
     std::vector<uint8_t> result;
     result.resize(dec.GetBlockSize(), 0);
@@ -540,7 +540,7 @@ static std::vector<uint8_t> DecryptThroughBase(const Decryptor<Impl> & dec,
     return result;
 }
 
-TEST(DesCryptTests, DecryptThroughBaseTest)
+TEST(DesCryptTests, DecryptGenericTest)
 {
     std::array<uint8_t, DesCrypt::KeySize> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
 
@@ -550,16 +550,16 @@ TEST(DesCryptTests, DecryptThroughBaseTest)
     DesCrypt::Key desKey(key.begin(), key.end());
     DesCrypt::Decryptor dec(desKey);
 
-    ASSERT_EQ(expected, DecryptThroughBase(dec, data.begin(), data.end()));
+    ASSERT_EQ(expected, DecryptGeneric(dec, data.begin(), data.end()));
 }
 
-template<typename Impl>
-static uint64_t DecryptUInt64BlockThroughBase(const Decryptor<Impl> & dec, uint64_t block)
+template<Decryptor DecryptorImpl>
+static uint64_t DecryptUInt64BlockGeneric(const DecryptorImpl & dec, uint64_t block)
 {
     return dec.DecryptBlock(block);
 }
 
-TEST(DesCryptTests, DecryptUInt64BlockThroughBaseTest)
+TEST(DesCryptTests, DecryptUInt64BlockGenericTest)
 {
     std::array<uint8_t, DesCrypt::KeySize> key = { 0x13, 0x34, 0x57, 0x79, 0x9b, 0xbc, 0xdf, 0xf1 };
 
@@ -569,5 +569,5 @@ TEST(DesCryptTests, DecryptUInt64BlockThroughBaseTest)
     DesCrypt::Key desKey(key.begin(), key.end());
     DesCrypt::Decryptor dec(desKey);
 
-    ASSERT_EQ(expected, DecryptUInt64BlockThroughBase(dec, data));
+    ASSERT_EQ(expected, DecryptUInt64BlockGeneric(dec, data));
 }
diff --git a/ChaosTests/Padding/PadderIso7816Tests.cpp b/ChaosTests/Padding/PadderIso7816Tests.cpp
index 0118032..e917063 100644
--- a/ChaosTests/Padding/PadderIso7816Tests.cpp
+++ b/ChaosTests/Padding/PadderIso7816Tests.cpp
@@ -109,8 +109,8 @@ TEST(PadIso7816Tests, PadOutIteratorUsageTest)
     }
 }
 
-template<typename Impl, typename OutputIt>
-void PadThroughBase(const Padder<Impl> & padder, OutputIt begin, OutputIt end)
+template<Padder PadderImpl, typename OutputIt>
+void PadGeneric(const PadderImpl & padder, OutputIt begin, OutputIt end)
 {
     padder.Pad(begin, end);
 }
@@ -127,7 +127,7 @@ TEST(PadIso7816Tests, PadThroughBaseTest)
         };
 
         const PadderIso7816 padder;
-        PadThroughBase(padder, fact.begin(), fact.end());
+        PadGeneric(padder, fact.begin(), fact.end());
 
         ASSERT_EQ(expected, fact);
     }
@@ -324,8 +324,8 @@ TEST(PadIso7816Tests, UnpadErrorTest)
     }
 }
 
-template<typename Impl, typename OutputIt>
-auto ComputeUnpadThroughBase(const Padder<Impl> & padder, OutputIt begin, OutputIt end)
+template<Padder PadderImpl, typename OutputIt>
+auto ComputeUnpadGeneric(const PadderImpl & padder, OutputIt begin, OutputIt end)
 {
     return padder.ComputeUnpad(begin, end);
 }
@@ -336,7 +336,7 @@ TEST(PadIso7816Tests, ComputeUnpadThroughBaseTest)
         std::array<uint8_t, 5> data = { 0x80, 0x00, 0x00, 0x00, 0x00 };
 
         const PadderIso7816 padder;
-        auto result = ComputeUnpadThroughBase(padder, data.begin(), data.end());
+        auto result = ComputeUnpadGeneric(padder, data.begin(), data.end());
 
         ASSERT_TRUE(result.IsOkay_);
         ASSERT_EQ(5, result.PadSize_);
diff --git a/ChaosTests/Padding/PadderPkcs7Tests.cpp b/ChaosTests/Padding/PadderPkcs7Tests.cpp
index 112918b..57240ac 100644
--- a/ChaosTests/Padding/PadderPkcs7Tests.cpp
+++ b/ChaosTests/Padding/PadderPkcs7Tests.cpp
@@ -137,8 +137,8 @@ TEST(PadPkcs7Tests, PadOutIteratorUsageTest)
     }
 }
 
-template<typename Impl, typename OutputIt>
-void PadThroughBase(const Padder<Impl> & padder, OutputIt begin, OutputIt end)
+template<Padder PadderImpl, typename OutputIt>
+void PadGeneric(const PadderImpl & padder, OutputIt begin, OutputIt end)
 {
     padder.Pad(begin, end);
 }
@@ -153,7 +153,7 @@ TEST(PadPkcs7Tests, PadThroughBaseTest)
         };
 
         const PadderPkcs7 padder;
-        PadThroughBase(padder, fact.begin(), fact.end());
+        PadGeneric(padder, fact.begin(), fact.end());
 
         ASSERT_EQ(expected, fact);
     }
@@ -347,8 +347,8 @@ TEST(PadPkcs7Tests, UnpadErrorTest)
     }
 }
 
-template<typename Impl, typename OutputIt>
-auto ComputeUnpadThroughBase(const Padder<Impl> & padder, OutputIt begin, OutputIt end)
+template<Padder PadderImpl, typename OutputIt>
+auto ComputeUnpadGeneric(const PadderImpl & padder, OutputIt begin, OutputIt end)
 {
     return padder.ComputeUnpad(begin, end);
 }
@@ -359,7 +359,7 @@ TEST(PadPkcs7Tests, ComputeUnpadThroughBaseTest)
         std::array<uint8_t, 5> data = { 0x05, 0x05, 0x05, 0x05, 0x05 };
 
         const PadderPkcs7 padder;
-        auto result = ComputeUnpadThroughBase(padder, data.begin(), data.end());
+        auto result = ComputeUnpadGeneric(padder, data.begin(), data.end());
 
         ASSERT_TRUE(result.IsOkay_);
         ASSERT_EQ(5, result.PadSize_);