diff --git a/dstr/include/dstr.h b/dstr/include/dstr.h
index fb46bc2..4e340ae 100644
--- a/dstr/include/dstr.h
+++ b/dstr/include/dstr.h
@@ -10,8 +10,8 @@ extern "C" {
 
 typedef struct dstr String;
 
-String *wapp_dstr_with_capacity(u64 capacity, Allocator *allocator);
-String *wapp_dstr_from_string(const char *str, Allocator *allocator);
+String *wapp_dstr_with_capacity(u64 capacity, const Allocator *allocator);
+String *wapp_dstr_from_string(const char *str, const Allocator *allocator);
 void wapp_dstr_update(String **dst, const char *src);
 void wapp_dstr_free(String **str);
 void wapp_dstr_concat(String **dst, const char *src);
diff --git a/dstr/src/dstr.c b/dstr/src/dstr.c
index 6b5f4ef..50e60b6 100644
--- a/dstr/src/dstr.c
+++ b/dstr/src/dstr.c
@@ -17,7 +17,7 @@ struct dstr {
   char buf[];
 };
 
-String *wapp_dstr_with_capacity(u64 capacity, Allocator *allocator) {
+String *wapp_dstr_with_capacity(u64 capacity, const Allocator *allocator) {
   Allocator alloc;
   if (allocator) {
     alloc = *allocator;
@@ -38,7 +38,7 @@ String *wapp_dstr_with_capacity(u64 capacity, Allocator *allocator) {
   return out;
 }
 
-String *wapp_dstr_from_string(const char *str, Allocator *allocator) {
+String *wapp_dstr_from_string(const char *str, const Allocator *allocator) {
   if (!str) {
     return NULL;
   }