diff --git a/src/app/asm/script.cc b/src/app/asm/script.cc
index 30535443..6bf86938 100644
--- a/src/app/asm/script.cc
+++ b/src/app/asm/script.cc
@@ -1,19 +1,28 @@
 #include "script.h"
 
-#include <asar.h>
+#include <interface-lib.h>
 
 #include <array>
 #include <fstream>
 #include <sstream>
 
+#include "absl/status/status.h"
 #include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
 #include "app/core/constants.h"
+#include "app/rom.h"
 
 namespace yaze {
 namespace app {
 namespace snes_asm {
 
+absl::Status Script::ApplyPatchToROM(ROM& rom) {
+  if (!asar_patch(patch_filename_, rom_.data(), patch_size_, rom_.size())) {
+    return absl::InternalError("Unable to apply patch");
+  }
+  return absl::OkStatus();
+}
+
 absl::StatusOr<absl::string_view> Script::GenerateMosaicChangeAssembly(
     std::array<int, core::kNumOverworldMaps> mosaic_tiles) {
   std::fstream file("assets/asm/mosaic_change.asm",
@@ -23,8 +32,8 @@ absl::StatusOr<absl::string_view> Script::GenerateMosaicChangeAssembly(
         "Couldn't open mosaic change template file");
   }
   std::stringstream assembly;
-
-  assembly << absl::StrCat("org ", kDefaultMosaicHook);
+  assembly << "org ";
+  assembly << kDefaultMosaicHook;
   assembly << file.rdbuf();
 
   file.close();
diff --git a/src/app/asm/script.h b/src/app/asm/script.h
index 49212e35..6d131551 100644
--- a/src/app/asm/script.h
+++ b/src/app/asm/script.h
@@ -1,15 +1,17 @@
 #ifndef YAZE_APP_ASM_SCRIPT_H
 #define YAZE_APP_ASM_SCRIPT_H
 
-#include <asar.h>
+#include <interface-lib.h>
 
 #include <array>
 #include <fstream>
 #include <sstream>
 
+#include "absl/status/status.h"
 #include "absl/status/statusor.h"
 #include "absl/strings/string_view.h"
 #include "app/core/constants.h"
+#include "app/rom.h"
 
 namespace yaze {
 namespace app {
@@ -19,8 +21,17 @@ constexpr char kDefaultMosaicHook[] = "$02AADB";
 
 class Script {
  public:
+  Script() = default;
+
+  absl::Status ApplyPatchToROM(ROM& rom);
+
   absl::StatusOr<absl::string_view> GenerateMosaicChangeAssembly(
       std::array<int, core::kNumOverworldMaps> mosaic_tiles);
+
+ private:
+  int64_t patch_size_;
+  std::string patch_filename_;
+  std::string patch_contents_;
 };
 
 }  // namespace snes_asm