diff --git a/libft/src/btree/btree_map.c b/libft/src/btree/btree_map.c
new file mode 100644
index 00000000..bdf27e07
--- /dev/null
+++ b/libft/src/btree/btree_map.c
@@ -0,0 +1,14 @@
+#include "btree.h"
+
+t_btree		*btree_map(t_btree *root, void *(*f)(void *item))
+{
+	t_btree		*new;
+
+	if (!root)
+		return (NULL);
+	new = btree_create_node(root->item, root->content_size);
+	new->item = (*f)(root->item);
+	new->left = btree_map(root->left, f);
+	new->right = btree_map(root->right, f);
+	return (new);
+}