diff --git a/boa/src/builtins/object/internal_state.rs b/boa/src/builtins/object/internal_state.rs
deleted file mode 100644
index 06955258cc5..00000000000
--- a/boa/src/builtins/object/internal_state.rs
+++ /dev/null
@@ -1,64 +0,0 @@
-//! Implementations for storing normal rust structs inside any object as internal state.
-
-use std::{
-    any::Any,
-    fmt::{self, Debug},
-    ops::{Deref, DerefMut},
-    rc::Rc,
-};
-
-use gc::{unsafe_empty_trace, Finalize, Trace};
-
-/// Wrapper around `Rc` to implement `Trace` and `Finalize`.
-#[derive(Clone)]
-pub struct InternalStateCell {
-    /// The internal state.
-    state: Rc<dyn Any>,
-}
-
-impl Finalize for InternalStateCell {}
-
-unsafe impl Trace for InternalStateCell {
-    unsafe_empty_trace!();
-}
-
-impl Deref for InternalStateCell {
-    type Target = dyn Any;
-    fn deref(&self) -> &Self::Target {
-        Deref::deref(&self.state)
-    }
-}
-
-impl DerefMut for InternalStateCell {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        Rc::get_mut(&mut self.state).expect("failed to get mutable")
-    }
-}
-
-/// The derived version would print 'InternalStateCell { state: ... }', this custom implementation
-/// only prints the actual internal state.
-impl Debug for InternalStateCell {
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        Debug::fmt(&self.state, f)
-    }
-}
-
-impl InternalStateCell {
-    /// Create new `InternalStateCell` from a value.
-    pub fn new<T: Any + InternalState>(value: T) -> Self {
-        Self {
-            state: Rc::new(value),
-        }
-    }
-    /// Get a reference to the stored value and cast it to `T`.
-    pub fn downcast_ref<T: Any + InternalState>(&self) -> Option<&T> {
-        self.deref().downcast_ref::<T>()
-    }
-    /// Get a mutable reference to the stored value and cast it to `T`.
-    pub fn downcast_mut<T: Any + InternalState>(&mut self) -> Option<&mut T> {
-        self.deref_mut().downcast_mut::<T>()
-    }
-}
-
-/// This trait must be implemented by all structs used for internal state.
-pub trait InternalState: Debug {}