diff --git a/pkgs/build-support/rust/fetch-cargo-deps b/pkgs/build-support/rust/fetch-cargo-deps
index 54593994990f..89b78547b38d 100755
--- a/pkgs/build-support/rust/fetch-cargo-deps
+++ b/pkgs/build-support/rust/fetch-cargo-deps
@@ -11,8 +11,11 @@ fetchCargoDeps() {
     echo "Using rust registry from $rustRegistry"
 
     cat <<EOF > $out/config
-[registry]
-index = "file://$rustRegistry"
+[source.nix-store-rust-registry]
+registry = "file://$rustRegistry"
+
+[source.crates-io]
+replace-with = "nix-store-rust-registry"
 EOF
 
     export CARGO_HOME=$out