diff --git a/vm/src/builtins/pysuper.rs b/vm/src/builtins/pysuper.rs
index 58c4dc6d0..a456ad854 100644
--- a/vm/src/builtins/pysuper.rs
+++ b/vm/src/builtins/pysuper.rs
@@ -58,12 +58,31 @@ impl PySuper {
         vm: &VirtualMachine,
     ) -> PyResult<PyRef<Self>> {
         // Get the type:
-        let typ = if let OptionalArg::Present(ty) = py_type {
-            ty
+        let (typ, obj) = if let OptionalArg::Present(ty) = py_type {
+            (ty, py_obj.unwrap_or_none(vm))
         } else {
             let frame = vm
                 .current_frame()
                 .ok_or_else(|| vm.new_runtime_error("super(): no current frame".to_owned()))?;
+
+            if frame.code.arg_count == 0 {
+                return Err(vm.new_runtime_error("super(): no arguments".to_owned()));
+            }
+            let obj = frame.fastlocals.lock()[0]
+                .clone()
+                .or_else(|| {
+                    if let Some(cell2arg) = frame.code.cell2arg.as_deref() {
+                        cell2arg[..frame.code.cellvars.len()]
+                            .iter()
+                            .enumerate()
+                            .find(|(_, arg_idx)| **arg_idx == 0)
+                            .and_then(|(cell_idx, _)| frame.cells_frees[cell_idx].get())
+                    } else {
+                        None
+                    }
+                })
+                .ok_or_else(|| vm.new_runtime_error("super(): arg[0] deleted".to_owned()))?;
+
             let mut typ = None;
             for (i, var) in frame.code.freevars.iter().enumerate() {
                 if var.borrow_value() == "__class__" {
@@ -80,46 +99,13 @@ impl PySuper {
                     break;
                 }
             }
-            typ.ok_or_else(|| {
+            let typ = typ.ok_or_else(|| {
                 vm.new_type_error(
                     "super must be called with 1 argument or from inside class method".to_owned(),
                 )
-            })?
-        };
+            })?;
 
-        // Check type argument:
-        if !typ.as_object().isinstance(&vm.ctx.types.type_type) {
-            return Err(vm.new_type_error(format!(
-                "super() argument 1 must be type, not {}",
-                typ.class().name
-            )));
-        }
-
-        // Get the bound object:
-        let obj = if let OptionalArg::Present(obj) = py_obj {
-            obj
-        } else {
-            let frame = vm
-                .current_frame()
-                .ok_or_else(|| vm.new_runtime_error("super(): no current frame".to_owned()))?;
-            if frame.code.arg_count == 0 {
-                return Err(vm.new_runtime_error("super(): no arguments".to_owned()));
-            }
-            let fastlocals = frame.fastlocals.lock();
-            fastlocals[0]
-                .clone()
-                .or_else(|| {
-                    if let Some(cell2arg) = frame.code.cell2arg.as_deref() {
-                        cell2arg[..frame.code.cellvars.len()]
-                            .iter()
-                            .enumerate()
-                            .find(|(_, arg_idx)| **arg_idx == 0)
-                            .and_then(|(cell_idx, _)| frame.cells_frees[cell_idx].get())
-                    } else {
-                        None
-                    }
-                })
-                .ok_or_else(|| vm.new_runtime_error("super(): arg[0] deleted".to_owned()))?
+            (typ, obj)
         };
 
         PySuper::new(typ, obj, vm)?.into_ref_with_type(vm, cls)
diff --git a/vm/src/frame.rs b/vm/src/frame.rs
index 872eed95c..aebf2816c 100644
--- a/vm/src/frame.rs
+++ b/vm/src/frame.rs
@@ -537,11 +537,25 @@ impl ExecutingFrame<'_> {
                 Ok(None)
             }
             bytecode::Instruction::DeleteLocal(idx) => {
-                self.locals.del_item(self.code.names[*idx].clone(), vm)?;
+                let name = &self.code.names[*idx];
+                match self.locals.del_item(name.clone(), vm) {
+                    Ok(()) => {}
+                    Err(e) if e.isinstance(&vm.ctx.exceptions.key_error) => {
+                        return Err(vm.new_name_error(format!("name '{}' is not defined", name)))
+                    }
+                    Err(e) => return Err(e),
+                }
                 Ok(None)
             }
             bytecode::Instruction::DeleteGlobal(idx) => {
-                self.globals.del_item(self.code.names[*idx].clone(), vm)?;
+                let name = &self.code.names[*idx];
+                match self.globals.del_item(name.clone(), vm) {
+                    Ok(()) => {}
+                    Err(e) if e.isinstance(&vm.ctx.exceptions.key_error) => {
+                        return Err(vm.new_name_error(format!("name '{}' is not defined", name)))
+                    }
+                    Err(e) => return Err(e),
+                }
                 Ok(None)
             }
             bytecode::Instruction::DeleteDeref(i) => {
diff --git a/wasm/lib/src/vm_class.rs b/wasm/lib/src/vm_class.rs
index 35fc59f13..edb62ff2a 100644
--- a/wasm/lib/src/vm_class.rs
+++ b/wasm/lib/src/vm_class.rs
@@ -17,7 +17,7 @@ use crate::wasm_builtins;
 
 pub(crate) struct StoredVirtualMachine {
     pub interp: Interpreter,
-    pub scope: RefCell<Scope>,
+    pub scope: Scope,
     /// you can put a Rc in here, keep it as a Weak, and it'll be held only for
     /// as long as the StoredVM is alive
     held_objects: RefCell<Vec<PyObjectRef>>,
@@ -47,7 +47,7 @@ impl StoredVirtualMachine {
 
         StoredVirtualMachine {
             interp,
-            scope: RefCell::new(scope.unwrap()),
+            scope: scope.unwrap(),
             held_objects: RefCell::new(Vec::new()),
         }
     }
@@ -203,8 +203,8 @@ impl WASMVirtualMachine {
     pub fn add_to_scope(&self, name: String, value: JsValue) -> Result<(), JsValue> {
         self.with_vm(move |vm, StoredVirtualMachine { ref scope, .. }| {
             let value = convert::js_to_py(vm, value);
-            scope.borrow_mut().store_name(&vm, name.as_str(), value);
-        })
+            scope.globals.set_item(name, value, vm).to_js(vm)
+        })?
     }
 
     #[wasm_bindgen(js_name = setStdout)]
@@ -264,7 +264,7 @@ impl WASMVirtualMachine {
                 }
             }
 
-            vm.run_code_obj(code, Scope::new(None, attrs.clone(), vm))
+            vm.run_code_obj(code, Scope::new(None, attrs.clone()))
                 .to_js(vm)?;
 
             let module = vm.new_module(&name, attrs);
@@ -309,7 +309,7 @@ impl WASMVirtualMachine {
             let source_path = source_path.unwrap_or_else(|| "<wasm>".to_owned());
             let code = vm.compile(source, mode, source_path);
             let code = code.map_err(convert::syntax_err)?;
-            let result = vm.run_code_obj(code, scope.borrow().clone());
+            let result = vm.run_code_obj(code, scope.clone());
             convert::pyresult_to_jsresult(vm, result)
         })?
     }