diff --git a/crates/jrsonnet-interner/Cargo.toml b/crates/jrsonnet-interner/Cargo.toml
index c70bc5bf..fba704da 100644
--- a/crates/jrsonnet-interner/Cargo.toml
+++ b/crates/jrsonnet-interner/Cargo.toml
@@ -9,3 +9,4 @@ edition = "2018"
 [dependencies]
 serde = { version = "1.0" }
 rustc-hash = "1.1.0"
+gc = { version = "0.4.1", features = ["derive"] }
\ No newline at end of file
diff --git a/crates/jrsonnet-interner/src/lib.rs b/crates/jrsonnet-interner/src/lib.rs
index 51a0a0d2..9fc23cda 100644
--- a/crates/jrsonnet-interner/src/lib.rs
+++ b/crates/jrsonnet-interner/src/lib.rs
@@ -1,3 +1,4 @@
+use gc::{unsafe_empty_trace, Finalize, Trace};
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use std::{
@@ -10,6 +11,10 @@ use std::{
 
 #[derive(Clone, PartialOrd, Ord, Eq)]
 pub struct IStr(Rc<str>);
+impl Finalize for IStr {}
+unsafe impl Trace for IStr {
+	unsafe_empty_trace!();
+}
 
 impl Deref for IStr {
 	type Target = str;