diff --git a/Makefile b/Makefile
index 28f5537..d6a7d44 100644
--- a/Makefile
+++ b/Makefile
@@ -4,8 +4,8 @@ BUILD:=_build
 # 	dune build src/core/oboy.exe
 
 core:
-	dune build src/core/oboy.so
-	cp _build/default/src/core/oboy.so $(BUILD)/liboboycore.so
+	dune build src/core/cbindings.exe.o
+	ar -rs $(BUILD)/liboboycore.a _build/default/src/core/cbindings.exe.o
 
 # check:
 # 	ocamlbuild -use-ocamlfind -I src -lflag -g test/test_bit.byte --
diff --git a/src/core/cbindings.ml b/src/core/cbindings.ml
new file mode 100644
index 0000000..39363db
--- /dev/null
+++ b/src/core/cbindings.ml
@@ -0,0 +1,3 @@
+let () =
+  Callback.register "name" Version.name;
+  Callback.register "version" Version.version;
diff --git a/src/core/dune b/src/core/dune
index 2226067..f5c530a 100644
--- a/src/core/dune
+++ b/src/core/dune
@@ -1,7 +1,12 @@
-; oboy.ml as the top-level file
+; cbindings.ml as the top-level file
 ; building a shared library because we are relying on pthread and we cannot
 ; combine static pthread with dynamic libc
 (executable
-	(name oboy)
-	(libraries threads)
-	(modes shared_object))
+	(name cbindings)
+	(modes object))
+
+; Standalone binary
+; TODO: split with core module
+;(executable
+;	(name main.ml)
+;	(libraries threads))
diff --git a/src/core/oboy.ml b/src/core/main.ml
similarity index 93%
rename from src/core/oboy.ml
rename to src/core/main.ml
index 6fd7568..521cf16 100644
--- a/src/core/oboy.ml
+++ b/src/core/main.ml
@@ -60,7 +60,7 @@ let power_up cartridge =
     run cpu mem screen
 
 
-(** let main =
+let () =
   if Array.length Sys.argv < 2 then begin
     prerr_endline "Please specify a ROM.";
     eprintf "Usage: %s path/to/rom\n" Sys.argv.(0);
@@ -70,8 +70,4 @@ let power_up cartridge =
   let cartridge = Cartridge.read_cartridge Sys.argv.(1) in
   match cartridge with
   | None -> print_endline "Invalid ROM file."
-  | Some c -> power_up c *)
-
-let () =
-  Callback.register "name" Version.name;
-  Callback.register "version" Version.version;
+  | Some c -> power_up c