Isolate variables at compile time

Cargo.toml

@@ -101,6 +101,7 @@ nix = { version = "0.26.4", default-features = false, features = ["term"] }
 [build-dependencies]
 anyhow = "1.0.75"
 indexmap = { version = "2.1.0", features = ["serde"] }
+itertools = "0.11.0"
 serde = { version = "1.0", features = ["derive"] }
 serde_with = "3.4.0"
 toml = { version = "0.8.6", features = ["preserve_order"] }