diff --git a/include/boost/mysql/connection.hpp b/include/boost/mysql/connection.hpp
index c4b0afb1..e95f23cd 100644
--- a/include/boost/mysql/connection.hpp
+++ b/include/boost/mysql/connection.hpp
@@ -3,7 +3,7 @@
 
 #include "boost/mysql/detail/protocol/channel.hpp"
 #include "boost/mysql/detail/network_algorithms/handshake.hpp"
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/protocol/protocol_types.hpp"
 #include "boost/mysql/error.hpp"
 #include "boost/mysql/resultset.hpp"
 #include "boost/mysql/prepared_statement.hpp"
diff --git a/include/boost/mysql/detail/aux/bytestring.hpp b/include/boost/mysql/detail/aux/bytestring.hpp
new file mode 100644
index 00000000..8737f9c0
--- /dev/null
+++ b/include/boost/mysql/detail/aux/bytestring.hpp
@@ -0,0 +1,21 @@
+#ifndef INCLUDE_BOOST_MYSQL_DETAIL_AUX_BYTESTRING_HPP_
+#define INCLUDE_BOOST_MYSQL_DETAIL_AUX_BYTESTRING_HPP_
+
+#include <vector>
+
+namespace boost {
+namespace mysql {
+namespace detail {
+
+template <typename Allocator>
+using basic_bytestring = std::vector<std::uint8_t, Allocator>;
+
+using bytestring = std::vector<std::uint8_t>;
+
+}
+}
+}
+
+
+
+#endif /* INCLUDE_BOOST_MYSQL_DETAIL_AUX_BYTESTRING_HPP_ */
diff --git a/include/boost/mysql/detail/aux/value_holder.hpp b/include/boost/mysql/detail/aux/value_holder.hpp
new file mode 100644
index 00000000..6d9bd06d
--- /dev/null
+++ b/include/boost/mysql/detail/aux/value_holder.hpp
@@ -0,0 +1,54 @@
+#ifndef INCLUDE_BOOST_MYSQL_DETAIL_AUX_VALUE_HOLDER_HPP_
+#define INCLUDE_BOOST_MYSQL_DETAIL_AUX_VALUE_HOLDER_HPP_
+
+#include <utility>
+
+namespace boost {
+namespace mysql {
+namespace detail {
+
+template <typename T>
+struct value_holder
+{
+	using value_type = T;
+
+	value_type value;
+
+	value_holder(): value{} {};
+
+	template <typename U>
+	explicit constexpr value_holder(U&& u): value(std::forward<U>(u)) {}
+
+	constexpr bool operator==(const value_holder<T>& rhs) const { return value == rhs.value; }
+	constexpr bool operator!=(const value_holder<T>& rhs) const { return value != rhs.value; }
+};
+
+// Operations on value holders
+struct get_value_type_helper
+{
+    struct no_value_type {};
+
+    template <typename T>
+    static constexpr typename T::value_type get(typename T::value_type*);
+
+    template <typename T>
+    static constexpr no_value_type get(...);
+};
+
+template <typename T>
+struct get_value_type
+{
+    using type = decltype(get_value_type_helper().get<T>(nullptr));
+    using no_value_type = get_value_type_helper::no_value_type;
+};
+
+template <typename T>
+using get_value_type_t = typename get_value_type<T>::type;
+
+}
+}
+}
+
+
+
+#endif /* INCLUDE_BOOST_MYSQL_DETAIL_AUX_VALUE_HOLDER_HPP_ */
diff --git a/include/boost/mysql/detail/network_algorithms/handshake.hpp b/include/boost/mysql/detail/network_algorithms/handshake.hpp
index 74311b6c..0b9e7b82 100644
--- a/include/boost/mysql/detail/network_algorithms/handshake.hpp
+++ b/include/boost/mysql/detail/network_algorithms/handshake.hpp
@@ -3,7 +3,7 @@
 
 #include <string_view>
 #include "boost/mysql/detail/protocol/channel.hpp"
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/protocol/protocol_types.hpp"
 #include "boost/mysql/collation.hpp"
 
 namespace boost {
diff --git a/include/boost/mysql/detail/protocol/channel.hpp b/include/boost/mysql/detail/protocol/channel.hpp
index 7e02748f..b731a707 100644
--- a/include/boost/mysql/detail/protocol/channel.hpp
+++ b/include/boost/mysql/detail/protocol/channel.hpp
@@ -2,7 +2,7 @@
 #define MYSQL_ASIO_IMPL_CHANNEL_HPP
 
 #include "boost/mysql/error.hpp"
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/aux/bytestring.hpp"
 #include "boost/mysql/detail/protocol/capabilities.hpp"
 #include <boost/asio/buffer.hpp>
 #include <boost/asio/async_result.hpp>
diff --git a/include/boost/mysql/detail/protocol/constants.hpp b/include/boost/mysql/detail/protocol/constants.hpp
index da5ec5cd..d70a8b5d 100644
--- a/include/boost/mysql/detail/protocol/constants.hpp
+++ b/include/boost/mysql/detail/protocol/constants.hpp
@@ -1,7 +1,7 @@
 #ifndef MYSQL_ASIO_IMPL_CONSTANTS_HPP
 #define MYSQL_ASIO_IMPL_CONSTANTS_HPP
 
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/protocol/protocol_types.hpp"
 
 namespace boost {
 namespace mysql {
diff --git a/include/boost/mysql/detail/protocol/impl/serialization.ipp b/include/boost/mysql/detail/protocol/impl/serialization.ipp
new file mode 100644
index 00000000..2e0d4a46
--- /dev/null
+++ b/include/boost/mysql/detail/protocol/impl/serialization.ipp
@@ -0,0 +1,125 @@
+#ifndef INCLUDE_BOOST_MYSQL_DETAIL_PROTOCOL_IMPL_SERIALIZATION_IPP_
+#define INCLUDE_BOOST_MYSQL_DETAIL_PROTOCOL_IMPL_SERIALIZATION_IPP_
+
+inline boost::mysql::errc boost::mysql::detail::deserialize(
+	int_lenenc& output,
+	deserialization_context& ctx
+) noexcept
+{
+	int1 first_byte;
+	errc err = deserialize(first_byte, ctx);
+	if (err != errc::ok)
+	{
+		return err;
+	}
+
+	if (first_byte.value == 0xFC)
+	{
+		int2 value;
+		err = deserialize(value, ctx);
+		output.value = value.value;
+	}
+	else if (first_byte.value == 0xFD)
+	{
+		int3 value;
+		err = deserialize(value, ctx);
+		output.value = value.value;
+	}
+	else if (first_byte.value == 0xFE)
+	{
+		int8 value;
+		err = deserialize(value, ctx);
+		output.value = value.value;
+	}
+	else
+	{
+		err = errc::ok;
+		output.value = first_byte.value;
+	}
+	return err;
+}
+
+inline void boost::mysql::detail::serialize(
+	int_lenenc input,
+	serialization_context& ctx
+) noexcept
+{
+	if (input.value < 251)
+	{
+		serialize(int1(static_cast<std::uint8_t>(input.value)), ctx);
+	}
+	else if (input.value < 0x10000)
+	{
+		ctx.write(0xfc);
+		serialize(int2(static_cast<std::uint16_t>(input.value)), ctx);
+	}
+	else if (input.value < 0x1000000)
+	{
+		ctx.write(0xfd);
+		serialize(int3(static_cast<std::uint32_t>(input.value)), ctx);
+	}
+	else
+	{
+		ctx.write(0xfe);
+		serialize(int8(static_cast<std::uint64_t>(input.value)), ctx);
+	}
+}
+
+inline std::size_t boost::mysql::detail::get_size(
+	int_lenenc input, const
+	serialization_context&
+) noexcept
+{
+	if (input.value < 251) return 1;
+	else if (input.value < 0x10000) return 3;
+	else if (input.value < 0x1000000) return 4;
+	else return 9;
+}
+
+inline boost::mysql::errc boost::mysql::detail::deserialize(
+	string_null& output,
+	deserialization_context& ctx
+) noexcept
+{
+	auto string_end = std::find(ctx.first(), ctx.last(), 0);
+	if (string_end == ctx.last())
+	{
+		return errc::incomplete_message;
+	}
+	output.value = get_string(ctx.first(), string_end-ctx.first());
+	ctx.set_first(string_end + 1); // skip the null terminator
+	return errc::ok;
+}
+
+inline boost::mysql::errc boost::mysql::detail::deserialize(
+	string_eof& output,
+	deserialization_context& ctx
+) noexcept
+{
+	output.value = get_string(ctx.first(), ctx.last()-ctx.first());
+	ctx.set_first(ctx.last());
+	return errc::ok;
+}
+
+inline boost::mysql::errc boost::mysql::detail::deserialize(
+	string_lenenc& output,
+	deserialization_context& ctx
+) noexcept
+{
+	int_lenenc length;
+	errc err = deserialize(length, ctx);
+	if (err != errc::ok)
+	{
+		return err;
+	}
+	if (!ctx.enough_size(length.value))
+	{
+		return errc::incomplete_message;
+	}
+
+	output.value = get_string(ctx.first(), length.value);
+	ctx.advance(length.value);
+	return errc::ok;
+}
+
+#endif /* INCLUDE_BOOST_MYSQL_DETAIL_PROTOCOL_IMPL_SERIALIZATION_IPP_ */
diff --git a/include/boost/mysql/detail/protocol/messages.hpp b/include/boost/mysql/detail/protocol/messages.hpp
index 4f17104f..c0993034 100644
--- a/include/boost/mysql/detail/protocol/messages.hpp
+++ b/include/boost/mysql/detail/protocol/messages.hpp
@@ -2,8 +2,9 @@
 #define MYSQL_ASIO_IMPL_MESSAGES_HPP
 
 #include "boost/mysql/detail/protocol/serialization.hpp"
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/protocol/protocol_types.hpp"
 #include "boost/mysql/detail/protocol/constants.hpp"
+#include "boost/mysql/detail/aux/bytestring.hpp"
 #include "boost/mysql/collation.hpp"
 #include "boost/mysql/value.hpp"
 #include <string>
diff --git a/include/boost/mysql/detail/basic_types.hpp b/include/boost/mysql/detail/protocol/protocol_types.hpp
similarity index 75%
rename from include/boost/mysql/detail/basic_types.hpp
rename to include/boost/mysql/detail/protocol/protocol_types.hpp
index 692835ac..0ab0916c 100644
--- a/include/boost/mysql/detail/basic_types.hpp
+++ b/include/boost/mysql/detail/protocol/protocol_types.hpp
@@ -1,6 +1,7 @@
 #ifndef MYSQL_ASIO_IMPL_BASIC_TYPES_HPP
 #define MYSQL_ASIO_IMPL_BASIC_TYPES_HPP
 
+#include "boost/mysql/detail/aux/value_holder.hpp"
 #include <cstdint>
 #include <string_view>
 #include <array>
@@ -11,22 +12,6 @@ namespace boost {
 namespace mysql {
 namespace detail {
 
-template <typename T>
-struct value_holder
-{
-	using value_type = T;
-
-	value_type value;
-
-	value_holder(): value{} {};
-
-	template <typename U>
-	explicit constexpr value_holder(U&& u): value(std::forward<U>(u)) {}
-
-	constexpr bool operator==(const value_holder<T>& rhs) const { return value == rhs.value; }
-	constexpr bool operator!=(const value_holder<T>& rhs) const { return value != rhs.value; }
-};
-
 struct int1 : value_holder<std::uint8_t> { using value_holder::value_holder; };
 struct int2 : value_holder<std::uint16_t> { using value_holder::value_holder; };
 struct int3 : value_holder<std::uint32_t> { using value_holder::value_holder; };
@@ -53,10 +38,6 @@ struct string_null : value_holder<std::string_view> { using value_holder::value_
 struct string_eof : value_holder<std::string_view> { using value_holder::value_holder; };
 struct string_lenenc : value_holder<std::string_view> { using value_holder::value_holder; };
 
-template <typename Allocator>
-using basic_bytestring = std::vector<std::uint8_t, Allocator>;
-
-using bytestring = std::vector<std::uint8_t>;
 
 } // detail
 } // mysql
diff --git a/include/boost/mysql/detail/protocol/serialization.hpp b/include/boost/mysql/detail/protocol/serialization.hpp
index 89487529..124f5d6b 100644
--- a/include/boost/mysql/detail/protocol/serialization.hpp
+++ b/include/boost/mysql/detail/protocol/serialization.hpp
@@ -6,9 +6,10 @@
 #include <type_traits>
 #include <algorithm>
 #include <variant>
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/protocol/protocol_types.hpp"
 #include "boost/mysql/detail/protocol/serialization_context.hpp"
 #include "boost/mysql/detail/protocol/deserialization_context.hpp"
+#include "boost/mysql/detail/aux/value_holder.hpp"
 #include "boost/mysql/error.hpp"
 
 namespace boost {
@@ -24,40 +25,14 @@ namespace detail {
  */
 
 // Fixed-size types
-struct get_value_type_helper
-{
-    struct no_value_type {};
-
-    template <typename T>
-    static constexpr typename T::value_type get(typename T::value_type*);
-
-    template <typename T>
-    static constexpr no_value_type get(...);
-};
-
-template <typename T>
-struct get_value_type
-{
-    using type = decltype(get_value_type_helper().get<T>(nullptr));
-    using no_value_type = get_value_type_helper::no_value_type;
-};
-
 template <typename T>
 struct is_fixed_size
 {
-private:
-	using value_type = typename get_value_type<T>::type;
-public:
 	static constexpr bool value =
-			std::is_integral_v<value_type> &&
-			std::is_base_of_v<value_holder<value_type>, T>;
+		std::is_integral<get_value_type_t<T>>::value &&
+		std::is_base_of<value_holder<get_value_type_t<T>>, T>::value;
 };
 
-// Serialization of these types relies on this fact
-static_assert(std::numeric_limits<float>::is_iec559);
-static_assert(std::numeric_limits<double>::is_iec559);
-
-
 template <> struct is_fixed_size<int_lenenc> : std::false_type {};
 template <std::size_t N> struct is_fixed_size<string_fixed<N>>: std::true_type {};
 
@@ -117,69 +92,9 @@ get_size(T, const serialization_context&) noexcept
 }
 
 // int_lenenc
-inline errc deserialize(int_lenenc& output, deserialization_context& ctx) noexcept
-{
-	int1 first_byte;
-	errc err = deserialize(first_byte, ctx);
-	if (err != errc::ok)
-	{
-		return err;
-	}
-
-	if (first_byte.value == 0xFC)
-	{
-		int2 value;
-		err = deserialize(value, ctx);
-		output.value = value.value;
-	}
-	else if (first_byte.value == 0xFD)
-	{
-		int3 value;
-		err = deserialize(value, ctx);
-		output.value = value.value;
-	}
-	else if (first_byte.value == 0xFE)
-	{
-		int8 value;
-		err = deserialize(value, ctx);
-		output.value = value.value;
-	}
-	else
-	{
-		err = errc::ok;
-		output.value = first_byte.value;
-	}
-	return err;
-}
-inline void serialize(int_lenenc input, serialization_context& ctx) noexcept
-{
-	if (input.value < 251)
-	{
-		serialize(int1(static_cast<std::uint8_t>(input.value)), ctx);
-	}
-	else if (input.value < 0x10000)
-	{
-		ctx.write(0xfc);
-		serialize(int2(static_cast<std::uint16_t>(input.value)), ctx);
-	}
-	else if (input.value < 0x1000000)
-	{
-		ctx.write(0xfd);
-		serialize(int3(static_cast<std::uint32_t>(input.value)), ctx);
-	}
-	else
-	{
-		ctx.write(0xfe);
-		serialize(int8(static_cast<std::uint64_t>(input.value)), ctx);
-	}
-}
-inline std::size_t get_size(int_lenenc input, const serialization_context&) noexcept
-{
-	if (input.value < 251) return 1;
-	else if (input.value < 0x10000) return 3;
-	else if (input.value < 0x1000000) return 4;
-	else return 9;
-}
+inline errc deserialize(int_lenenc& output, deserialization_context& ctx) noexcept;
+inline void serialize(int_lenenc input, serialization_context& ctx) noexcept;
+inline std::size_t get_size(int_lenenc input, const serialization_context&) noexcept;
 
 // Helper for strings
 inline std::string_view get_string(const std::uint8_t* from, std::size_t size)
@@ -188,17 +103,7 @@ inline std::string_view get_string(const std::uint8_t* from, std::size_t size)
 }
 
 // string_null
-inline errc deserialize(string_null& output, deserialization_context& ctx) noexcept
-{
-	auto string_end = std::find(ctx.first(), ctx.last(), 0);
-	if (string_end == ctx.last())
-	{
-		return errc::incomplete_message;
-	}
-	output.value = get_string(ctx.first(), string_end-ctx.first());
-	ctx.set_first(string_end + 1); // skip the null terminator
-	return errc::ok;
-}
+inline errc deserialize(string_null& output, deserialization_context& ctx) noexcept;
 inline void serialize(string_null input, serialization_context& ctx) noexcept
 {
 	ctx.write(input.value.data(), input.value.size());
@@ -210,12 +115,7 @@ inline std::size_t get_size(string_null input, const serialization_context&) noe
 }
 
 // string_eof
-inline errc deserialize(string_eof& output, deserialization_context& ctx) noexcept
-{
-	output.value = get_string(ctx.first(), ctx.last()-ctx.first());
-	ctx.set_first(ctx.last());
-	return errc::ok;
-}
+inline errc deserialize(string_eof& output, deserialization_context& ctx) noexcept;
 inline void serialize(string_eof input, serialization_context& ctx) noexcept
 {
 	ctx.write(input.value.data(), input.value.size());
@@ -226,35 +126,15 @@ inline std::size_t get_size(string_eof input, const serialization_context&) noex
 }
 
 // string_lenenc
-inline errc deserialize(string_lenenc& output, deserialization_context& ctx) noexcept
-{
-	int_lenenc length;
-	errc err = deserialize(length, ctx);
-	if (err != errc::ok)
-	{
-		return err;
-	}
-	if (!ctx.enough_size(length.value))
-	{
-		return errc::incomplete_message;
-	}
-
-	output.value = get_string(ctx.first(), length.value);
-	ctx.advance(length.value);
-	return errc::ok;
-}
+inline errc deserialize(string_lenenc& output, deserialization_context& ctx) noexcept;
 inline void serialize(string_lenenc input, serialization_context& ctx) noexcept
 {
-	int_lenenc length;
-	length.value = input.value.size();
-	serialize(length, ctx);
+	serialize(int_lenenc(input.value.size()), ctx);
 	ctx.write(input.value.data(), input.value.size());
 }
 inline std::size_t get_size(string_lenenc input, const serialization_context& ctx) noexcept
 {
-	int_lenenc length;
-	length.value = input.value.size();
-	return get_size(length, ctx) + input.value.size();
+	return get_size(int_lenenc(input.value.size()), ctx) + input.value.size();
 }
 
 // Enums
@@ -285,6 +165,9 @@ std::size_t get_size(T, const serialization_context&) noexcept
 }
 
 // Floating points
+static_assert(std::numeric_limits<float>::is_iec559);
+static_assert(std::numeric_limits<double>::is_iec559);
+
 template <typename T, typename=std::enable_if_t<std::is_floating_point_v<T>>>
 errc deserialize(value_holder<T>& output, deserialization_context& ctx) noexcept
 {
@@ -486,11 +369,10 @@ inline std::size_t get_size(dummy_serializable, const serialization_context&) no
 inline void serialize(dummy_serializable, serialization_context&) noexcept {}
 inline errc deserialize(dummy_serializable, deserialization_context&) noexcept { return errc::ok; }
 
-template <typename T>
-constexpr bool is_fixed_size_fn() { return is_fixed_size<T>::value; }
-
 } // detail
 } // mysql
 } // boost
 
+#include "boost/mysql/detail/protocol/impl/serialization.ipp"
+
 #endif
diff --git a/include/boost/mysql/metadata.hpp b/include/boost/mysql/metadata.hpp
index e289d94a..c60c9505 100644
--- a/include/boost/mysql/metadata.hpp
+++ b/include/boost/mysql/metadata.hpp
@@ -2,7 +2,7 @@
 #define MYSQL_ASIO_METADATA_HPP
 
 #include "boost/mysql/detail/protocol/messages.hpp"
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/aux/bytestring.hpp"
 #include "boost/mysql/field_type.hpp"
 
 namespace boost {
diff --git a/include/boost/mysql/resultset.hpp b/include/boost/mysql/resultset.hpp
index b9bdb314..7c4f9b48 100644
--- a/include/boost/mysql/resultset.hpp
+++ b/include/boost/mysql/resultset.hpp
@@ -5,6 +5,7 @@
 #include "boost/mysql/metadata.hpp"
 #include "boost/mysql/detail/protocol/messages.hpp"
 #include "boost/mysql/detail/protocol/channel.hpp"
+#include "boost/mysql/detail/aux/bytestring.hpp"
 #include "boost/mysql/detail/network_algorithms/common.hpp" // deserialize_row_fn
 #include <boost/asio/ip/tcp.hpp>
 #include <cassert>
diff --git a/include/boost/mysql/row.hpp b/include/boost/mysql/row.hpp
index d690b0c1..cb3aa42d 100644
--- a/include/boost/mysql/row.hpp
+++ b/include/boost/mysql/row.hpp
@@ -1,10 +1,10 @@
 #ifndef MYSQL_ASIO_ROW_HPP
 #define MYSQL_ASIO_ROW_HPP
 
-#include "boost/mysql/detail/basic_types.hpp"
+#include "boost/mysql/detail/aux/bytestring.hpp"
+#include "boost/mysql/detail/aux/container_equals.hpp"
 #include "boost/mysql/value.hpp"
 #include "boost/mysql/metadata.hpp"
-#include "boost/mysql/detail/aux/container_equals.hpp"
 #include <algorithm>
 
 namespace boost {