I've discovered this while trying to use it on a M1 Macbook (an `aarch64-darwin` system). The change makes sure it will work by default on most systems by default. The user would use this parameter only to restrict the systems if necessary.
Since Flake resolves both namespaces, and legacyPackages is more forgiving, use that and not deal with the subtle differences.
closes #21
zah
Jonas Chevalier
David Arnold