feat(fs): add configuration for xfs, ext4, btrfs

faucet/fs/btrfs.nix

@@ -0,0 +1,22 @@
+{ pkgs
+, lib
+, config
+, ... }: with lib; let
+  cfg = config.faucet.fs;
+in {
+  options.faucet.fs.btrfs = {
+    options = mkOption {
+      type = with types; listOf str;
+      default = [ "noatime" "compress=zstd" ];
+      description = "btrfs mount options";
+    };
+  };
+
+  config = mkIf (cfg.type == "btrfs") {
+    fileSystems."/nix" =
+    { inherit (cfg.btrfs) options;
+      device = "/dev/disk/by-uuid/${cfg.store}";
+      fsType = "btrfs";
+    };
+  };
+}