diff --git a/repl/lib_runner.c b/repl/lib_runner.c
index 04fbc57..6089781 100644
--- a/repl/lib_runner.c
+++ b/repl/lib_runner.c
@@ -7,6 +7,7 @@
 
 #include <stdio.h>
 #include <stdlib.h>
+#include <string.h>
 
 typedef struct Toy_Runner {
 	Toy_Interpreter interpreter;
diff --git a/repl/lib_standard.c b/repl/lib_standard.c
index 57fdbb3..92dfb90 100644
--- a/repl/lib_standard.c
+++ b/repl/lib_standard.c
@@ -2,9 +2,10 @@
 
 #include "toy_memory.h"
 
-#include <ctype.h>
 #include <stdio.h>
+#include <string.h>
 #include <time.h>
+#include <ctype.h>
 
 static int nativeClock(Toy_Interpreter* interpreter, Toy_LiteralArray* arguments) {
 	//no arguments
diff --git a/source/toy_builtin.c b/source/toy_builtin.c
index 399a57e..0dbfc11 100644
--- a/source/toy_builtin.c
+++ b/source/toy_builtin.c
@@ -4,6 +4,7 @@
 #include "toy_literal.h"
 
 #include <stdio.h>
+#include <string.h>
 
 //static math utils, copied from the interpreter
 static Toy_Literal addition(Toy_Interpreter* interpreter, Toy_Literal lhs, Toy_Literal rhs) {
diff --git a/source/toy_compiler.c b/source/toy_compiler.c
index dcdaef3..47893fd 100644
--- a/source/toy_compiler.c
+++ b/source/toy_compiler.c
@@ -9,6 +9,7 @@
 #include "toy_console_colors.h"
 
 #include <stdio.h>
+#include <string.h>
 
 void Toy_initCompiler(Toy_Compiler* compiler) {
 	Toy_initLiteralArray(&compiler->literalCache);
diff --git a/source/toy_literal.c b/source/toy_literal.c
index 61944ce..abf17e7 100644
--- a/source/toy_literal.c
+++ b/source/toy_literal.c
@@ -8,6 +8,7 @@
 #include "toy_console_colors.h"
 
 #include <stdio.h>
+#include <string.h>
 
 //hash util functions
 static unsigned int hashString(const char* string, int length) {
diff --git a/source/toy_literal.h b/source/toy_literal.h
index ed7ad02..f205fbf 100644
--- a/source/toy_literal.h
+++ b/source/toy_literal.h
@@ -12,8 +12,6 @@ typedef int (*Toy_NativeFn)(struct Toy_Interpreter* interpreter, struct Toy_Lite
 typedef int (*Toy_HookFn)(struct Toy_Interpreter* interpreter, struct Toy_Literal identifier, struct Toy_Literal alias);
 typedef void (*Toy_PrintFn)(const char*);
 
-#include <string.h>
-
 typedef enum {
 	TOY_LITERAL_NULL,
 	TOY_LITERAL_BOOLEAN,
diff --git a/source/toy_refstring.c b/source/toy_refstring.c
index 6ddb576..3fd0173 100644
--- a/source/toy_refstring.c
+++ b/source/toy_refstring.c
@@ -1,7 +1,5 @@
 #include "toy_refstring.h"
 
-#include <string.h>
-
 //memory allocation
 extern void* Toy_private_defaultMemoryAllocator(void* pointer, size_t oldSize, size_t newSize);
 static Toy_RefStringAllocatorFn allocate = Toy_private_defaultMemoryAllocator;
diff --git a/source/toy_refstring.h b/source/toy_refstring.h
index 02bbaf9..2928b6e 100644
--- a/source/toy_refstring.h
+++ b/source/toy_refstring.h
@@ -1,10 +1,9 @@
 #pragma once
 
-#include <stdbool.h>
-#include <stddef.h>
-
 #include "toy_common.h"
 
+#include <string.h>
+
 //memory allocation hook
 typedef void* (*Toy_RefStringAllocatorFn)(void* pointer, size_t oldSize, size_t newSize);
 TOY_API void Toy_setRefStringAllocatorFn(Toy_RefStringAllocatorFn);