diff --git a/src/verus.rs b/src/verus.rs
index 8a43e8b..4a49ac4 100644
--- a/src/verus.rs
+++ b/src/verus.rs
@@ -1492,7 +1492,7 @@ pub mod install {
         let cmd = &mut Command::new("bash");
         cmd.current_dir(verus_source_dir())
             .env_remove("RUSTUP_TOOLCHAIN")
-            .env("RUSTUP_TOOLCHAIN", toolchain_name)
+            .env("RUSTUP_TOOLCHAIN", toolchain_name.clone())
             .arg("-c")
             .arg(format!(
                 "source ../tools/activate; vargo build {} --features singular",