{ config, lib, pkgs, ... }:

{
  # ─────────────────────────────────────────────
  # Bootloader generation limit (rollback window)
  # ─────────────────────────────────────────────
  boot.loader.systemd-boot.configurationLimit = 3;
  # If you're using GRUB instead, use this instead:
  # boot.loader.grub.configurationLimit = 3;

  # ─────────────────────────────────────────────
  # Nix garbage collection (tight retention)
  # ─────────────────────────────────────────────
  nix.gc = {
    automatic = true;
    dates = "daily";
    options = "--delete-older-than 3d";
  };

  # ─────────────────────────────────────────────
  # Store optimisation (reduce disk bloat)
  # ─────────────────────────────────────────────
  nix.settings.auto-optimise-store = true;

  # ─────────────────────────────────────────────
  # Optional: keep system leaner overall
  # (reduces leftover system profiles slightly)
  # ─────────────────────────────────────────────
  nix.settings.keep-outputs = false;
  nix.settings.keep-derivations = false;
}