diff --git a/nix/shell.nix b/nix/shell.nix
index 8b8d0a0..9b37289 100644
--- a/nix/shell.nix
+++ b/nix/shell.nix
@@ -24,7 +24,7 @@ in
       # This is not exactly necessary, but it allows for compiling for various targets
       # with the least amount of friction.
       (rust-bin.nightly.latest.default.override {
-        extensions = ["rustfmt" "rust-analyzer" "clippy" "rust-analyzer"] ++ extraComponents;
+        extensions = ["rustfmt" "rust-src" "rust-analyzer" "clippy" "rust-analyzer"] ++ extraComponents;
         targets =
           [
             "wasm32-unknown-unknown" # web