diff --git a/include/pocketpy/interpreter/vm.h b/include/pocketpy/interpreter/vm.h
index aa1887b4..e1a3882f 100644
--- a/include/pocketpy/interpreter/vm.h
+++ b/include/pocketpy/interpreter/vm.h
@@ -32,6 +32,7 @@ typedef struct VM {
     bool is_curr_exc_handled;  // handled by try-except block but not cleared yet
 
     py_TValue reg[8];  // users' registers
+    void* ctx;         // user-defined context
 
     py_StackRef __curr_class;
     py_StackRef __curr_function;
diff --git a/include/pocketpy/pocketpy.h b/include/pocketpy/pocketpy.h
index 15fb556a..1f7b0393 100644
--- a/include/pocketpy/pocketpy.h
+++ b/include/pocketpy/pocketpy.h
@@ -92,6 +92,10 @@ PK_EXPORT int py_currentvm();
 PK_EXPORT void py_switchvm(int index);
 /// Reset the current VM.
 PK_EXPORT void py_resetvm();
+/// Get the current VM context. This is used for user-defined data.
+PK_EXPORT void* py_getvmctx();
+/// Set the current VM context. This is used for user-defined data.
+PK_EXPORT void py_setvmctx(void* ctx);
 /// Set `sys.argv`. Used for storing command-line arguments.
 PK_EXPORT void py_sys_setargv(int argc, char** argv);
 /// Setup the callbacks for the current VM.
diff --git a/src/interpreter/vm.c b/src/interpreter/vm.c
index 04624f57..31141e51 100644
--- a/src/interpreter/vm.c
+++ b/src/interpreter/vm.c
@@ -71,6 +71,7 @@ void VM__ctor(VM* self) {
     self->curr_exception = *py_NIL;
     self->is_curr_exc_handled = false;
 
+    self->ctx = NULL;
     self->__curr_class = NULL;
     self->__curr_function = NULL;
 
diff --git a/src/public/internal.c b/src/public/internal.c
index 12eef91f..b5e6037d 100644
--- a/src/public/internal.c
+++ b/src/public/internal.c
@@ -75,6 +75,14 @@ int py_currentvm() {
     return -1;
 }
 
+void* py_getvmctx(){
+    return pk_current_vm->ctx;
+}
+
+void py_setvmctx(void* ctx){
+    pk_current_vm->ctx = ctx;
+}
+
 void py_sys_setargv(int argc, char** argv) {
     py_GlobalRef sys = py_getmodule("sys");
     py_Ref argv_list = py_getdict(sys, py_name("argv"));