diff --git a/src/ast.c b/src/ast.c
index 4f33a63..d08c224 100644
--- a/src/ast.c
+++ b/src/ast.c
@@ -2,21 +2,8 @@
 
 #include <stdlib.h>
 #include <stdio.h>
-#include <string.h>
 
-char* strdup (const char* s)
-{
-    size_t slen = strlen(s);
-    char* result = malloc(slen + 1);
-
-    if(result == NULL)
-    {
-        return NULL;
-    }
-
-    memcpy(result, s, slen+1);
-    return result;
-}
+#include "util.h"
 
 const char* SyntaxKindString(SyntaxKind syntaxKind)
 {
diff --git a/src/ast.h b/src/ast.h
index 8e49ace..5c04d76 100644
--- a/src/ast.h
+++ b/src/ast.h
@@ -89,7 +89,6 @@ typedef struct Node
     PrimitiveType primitiveType;
 } Node;
 
-char* strdup (const char* s);
 const char* SyntaxKindString(SyntaxKind syntaxKind);
 
 uint8_t IsPrimitiveType(Node *typeNode);
diff --git a/src/util.c b/src/util.c
new file mode 100644
index 0000000..ae1654f
--- /dev/null
+++ b/src/util.c
@@ -0,0 +1,16 @@
+#include "util.h"
+
+#include <string.h>
+
+char* strdup (const char* s)
+{
+  size_t slen = strlen(s);
+  char* result = malloc(slen + 1);
+  if(result == NULL)
+  {
+    return NULL;
+  }
+
+  memcpy(result, s, slen+1);
+  return result;
+}
\ No newline at end of file
diff --git a/src/util.h b/src/util.h
new file mode 100644
index 0000000..2c305ec
--- /dev/null
+++ b/src/util.h
@@ -0,0 +1,6 @@
+#ifndef WRAITH_UTIL_H
+#define WRAITH_UTIL_H
+
+char* strdup (const char* s);
+
+#endif /* WRAITH_UTIL_H */