diff --git a/src/interpreter.c b/src/interpreter.c
index c40c420..61e4e01 100644
--- a/src/interpreter.c
+++ b/src/interpreter.c
@@ -148,6 +148,33 @@ GroundVariable* findVariable(GroundVariable* head, const char *id) {
 }
 
 void deleteVariable(GroundVariable** head, GroundVariable *item) {
+    if (strcmp(item->id, "self") == 0) {
+        return;
+    }
+    if (item->value.type == CUSTOM) {
+        GroundObjectField* destructor = findField(*item->value.data.customVal, "destructor");
+        if (destructor != NULL) {
+            if (destructor->value.type == FUNCTION) {
+                GroundScope scope = {
+                    .labels = NULL,
+                    .variables = malloc(sizeof(GroundVariable*)),
+                    .isMainScope = false
+                };
+                if (scope.variables == NULL) {
+                    runtimeError(FIXME, "Failed to allocate memory for scope variables", NULL, -1);
+                }
+                *scope.variables = NULL;
+                addVariable(scope.variables, "self", item->value);
+                GroundInstruction instruction = createGroundInstruction(CALLMETHOD);
+                addArgToInstruction(&instruction, createRefGroundArg(DIRREF, "self"));
+                addArgToInstruction(&instruction, createRefGroundArg(FNREF, "destructor"));
+                addArgToInstruction(&instruction, createRefGroundArg(DIRREF, ""));
+                interpretGroundInstruction(instruction, &scope);
+            } else {
+                runtimeError(ARG_TYPE_MISMATCH, "Custom type destructor must be a function", NULL, -1);
+            }
+        }
+    }
     HASH_DEL(*head, item);
     free(item);
 }
@@ -1922,6 +1949,13 @@ GroundValue interpretGroundInstruction(GroundInstruction inst, GroundScope* scop
                 if (returnValue.type != function->returnType) {
                     runtimeError(RETURN_TYPE_MISMATCH, "Unexpected return value type from function", in, currentInstruction);
                 }
+
+                GroundVariable* var, *tmp;
+
+                HASH_ITER(hh, *newScope.variables, var, tmp) {
+                    deleteVariable(newScope.variables, var);
+                }
+
                 addVariable(scope->variables, in->args.args[in->args.length - 1].value.refName, returnValue);
                 currentInstruction = currentCurrentInstruction;
             }