diff --git a/include/rexy/string_base.tpp b/include/rexy/string_base.tpp
index 4ebae7b..a19dbed 100644
--- a/include/rexy/string_base.tpp
+++ b/include/rexy/string_base.tpp
@@ -19,10 +19,10 @@
 #ifndef REXY_STRING_BASE_TPP
 #define REXY_STRING_BASE_TPP
 
-#include <utility> //forward, move, swap, etc
-#include <cstring> //strlen, strcpy
+#include <utility> //move, etc
+#include <type_traits> //is_nothrow_invokable, is_nothrow_constructible
 
-#include "utility.hpp" //max, memcpy
+#include "utility.hpp" //max, memcpy, strlen
 #include "detail/string_appender.hpp"
 #include "algorithm.hpp"
 #include "compat/to_address.hpp"
@@ -42,7 +42,7 @@ namespace rexy{
 	}
 	template<class Char>
 	constexpr auto string_base<Char>::search(const_pointer c)const -> const_iterator{
-		const auto len = strlen(c);
+		const auto len = rexy::strlen(c);
 		return two_way_search(cbegin(), cend(), c, c + len);
 	}
 	template<class Char>
@@ -51,7 +51,7 @@ namespace rexy{
 	}
 	template<class Char>
 	constexpr auto string_base<Char>::search(const_pointer c) -> iterator{
-		const auto len = strlen(c);
+		const auto len = rexy::strlen(c);
 		return two_way_search(begin(), end(), c, c + len);
 	}
 	template<class Char>
@@ -62,7 +62,7 @@ namespace rexy{
 	template<class Char>
 	template<class Searcher>
 	constexpr auto string_base<Char>::search(const_pointer c, const Searcher& searcher)const -> const_iterator{
-		const auto len = strlen(c);
+		const auto len = rexy::strlen(c);
 		return searcher(cbegin(), cend(), c, c + len);
 	}
 	template<class Char>
@@ -73,7 +73,7 @@ namespace rexy{
 	template<class Char>
 	template<class Searcher>
 	constexpr auto string_base<Char>::search(const_pointer c, const Searcher& searcher) -> iterator{
-		const auto len = strlen(c);
+		const auto len = rexy::strlen(c);
 		return searcher(begin(), end(), c, c + len);
 	}
 
@@ -106,7 +106,7 @@ namespace rexy{
 	constexpr basic_string<Char,Alloc>::basic_string(void)noexcept{}
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	constexpr basic_string<Char,Alloc>::basic_string(rexy::steal<pointer> data)noexcept:
-		basic_string(data.value(), data.value() ? strlen(data.value()) : 0){}
+		basic_string(data.value(), data.value() ? rexy::strlen(data.value()) : 0){}
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	constexpr basic_string<Char,Alloc>::basic_string(rexy::steal<pointer> data, size_type len)noexcept:
 		string_base<Char>(data.value(), len, len){}
@@ -126,7 +126,7 @@ namespace rexy{
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	REXY_CPP20_CONSTEXPR basic_string<Char,Alloc>::basic_string(const_pointer data)
 		noexcept(is_nothrow_allocator_v<Alloc>):
-		basic_string(data, data ? strlen(data) : 0){}
+		basic_string(data, data ? rexy::strlen(data) : 0){}
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	REXY_CPP20_CONSTEXPR basic_string<Char,Alloc>::basic_string(size_type cap)
 		noexcept(is_nothrow_allocator_v<Alloc>):
@@ -222,7 +222,7 @@ namespace rexy{
 	REXY_CPP20_CONSTEXPR basic_string<Char,Alloc>& basic_string<Char,Alloc>::operator=(const_pointer c)
 		noexcept(is_nothrow_allocator_v<Alloc>)
 	{
-		return _copy_string(c, strlen(c));
+		return _copy_string(c, rexy::strlen(c));
 	}
 
 	//Replace managed pointer. Frees existing value
@@ -230,7 +230,7 @@ namespace rexy{
 	REXY_CPP20_CONSTEXPR void basic_string<Char,Alloc>::reset(pointer val)
 		noexcept(is_nothrow_allocator_v<Alloc>)
 	{
-		reset(val, val ? strlen(val) : 0);
+		reset(val, val ? rexy::strlen(val) : 0);
 	}
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	REXY_CPP20_CONSTEXPR void basic_string<Char,Alloc>::reset(pointer val, size_type len)
@@ -286,7 +286,7 @@ namespace rexy{
 		noexcept(is_nothrow_allocator_v<Alloc>)
 	{
 		if(data)
-			append(data, strlen(data));
+			append(data, rexy::strlen(data));
 	}
 	template<class Char, REXY_ALLOCATOR_CONCEPT Alloc>
 	template<class InputIt>