Infrastructure repositories tend to want an exact version of tools. It’s desirable that when I work on Terraform code on my laptop, I use the same version as will be used in production, and the same version that my colleagues use. While I like to use Nix Flakes for per-project development environments, nixpkgs is not much help here. It carries a single version of each of these tools — whichever one happened to be current when the package was last bumped — and it builds them from source. Both of those are the right defaults for a distribution and the wrong ones for pinning a team to terraform 1.9.8 specifically, verified against the checksum HashiCorp published for it.