feat(xatu): scaffold project

Add the Xatu Rust package as a minimal hello-world skeleton with Cargo workspace metadata and Bazel library, binary, and test targets.

AGENTS.md

@@ -98,9 +98,14 @@
 - Rust tests in this monorepo live in separate `*_test.rs` files, not inline `#[cfg(test)]` modules.
 - Ariadne Rust tests are declared in Bazel `BUILD` files; do not add `[[test]]` entries to
   `src/ariadne/Cargo.toml` unless explicitly requested.
+- Rust package validation in this monorepo uses Bazel `rust_test` targets.
+  Do not claim or require `cargo test` as the standard Rust validation path unless explicitly requested.
 - In this monorepo, "dotfiles" refers to the dotfiles/NixOS configuration under `src/dotfiles/` and `configs/nixos/`.
 - The flake does not currently define `formatter.x86_64-linux`.
   Do not use `nix fmt` as a validation command until a formatter is added.
+- Keep `third_party/**` excluded from treefmt.
+  Vendored code can contain syntax fixtures, generated files, or upstream formatting that local
+  formatters must not rewrite.
 - Ariadne extraction must preserve the game-root season prefix for archived source.
   Different game installs can contain compiled scripts with the same internal path.
 - Clew owns Ren'Py extraction, preparation, and compiled-script AST export. Ariadne owns analysis over Clew-produced data.
@@ -114,3 +119,5 @@
   Do not use `git subtree add` or `git subtree pull` for Pi PR branches.
   Gitea rebases the synthetic upstream root commit without the `third_party/pi` prefix.
   Preserve `git-subtree-dir` and `git-subtree-split` trailers on Pi vendor commits.
+- `rules_rust` `crates_vendor` can vendor direct crate specs through the `packages` attribute.
+  Do not create a placeholder Rust package only to anchor a future vendored dependency.

src/dotfiles/apps.nix

@@ -15,14 +15,9 @@ in
         name = "fix";
         runtimeInputs = [
           formatter
-          pkgs.statix
-          pkgs.deadnix
         ];
         text = ''
           treefmt
-          statix fix .
-          deadnix --edit --exclude configs/nixos/hosts/*/hardware-configuration.nix -- .
-          treefmt
         '';
       }
     );

src/dotfiles/formatter.nix

@@ -6,5 +6,6 @@ inputs.treefmt-nix.lib.evalModule inputs.nixpkgs.legacyPackages.${system} {
 
   settings.formatter.nixfmt.excludes = [
     "configs/nixos/hosts/*/hardware-configuration.nix"
+    "third_party/**"
   ];
 }

src/dotfiles/registry.nix

@@ -4,211 +4,26 @@
   root,
 }:
 let
-  checkType = lib.types.submodule {
-    options = {
-      assertion = lib.mkOption {
-        type = lib.types.functionTo lib.types.bool;
-        description = ''
-          Predicate run against this registry's flattened collected entries.
-        '';
-      };
+  definitionModule = import ./registry/definition-module.nix { inherit lib; };
 
-      message = lib.mkOption {
-        type = lib.types.str;
-        description = ''
-          Error message shown when this registry validation check fails.
-        '';
-      };
-    };
+  definitions = import ./registry/definitions.nix {
+    inherit lib root;
+    inherit (definitionModule) registryDefinitionModule registryLib;
   };
 
-  predicates = {
-    uniqueValue =
-      value: entries: builtins.length (lib.unique (map value entries)) == builtins.length entries;
+  registryOption = import ./registry/options.nix { inherit lib; };
+
+  collection = import ./registry/collect.nix {
+    inherit definitions lib;
   };
 
-  registryLib = lib // {
-    registry = (lib.registry or { }) // {
-      inherit predicates;
-    };
+  validation = import ./registry/validation.nix {
+    inherit definitions lib;
   };
 
-  registryDefinitionModule = {
-    options = {
-      type = lib.mkOption {
-        type = lib.types.raw;
-        description = ''
-          NixOS option type for one registry entry.
-        '';
-      };
-
-      replicate = lib.mkOption {
-        type = lib.types.bool;
-        default = false;
-        description = ''
-          Whether collected entries are merged and published under every host key.
-        '';
-      };
-
-      checks = lib.mkOption {
-        type = lib.types.listOf checkType;
-        default = [ ];
-        description = ''
-          Validation checks for this registry's flattened collected entries.
-        '';
-      };
-    };
+  operations = import ./registry/operations.nix {
+    inherit definitions lib;
   };
-
-  registryName = fileName: lib.removeSuffix ".nix" fileName;
-
-  registryOption =
-    registry:
-    lib.mkOption {
-      type = lib.types.attrsOf (lib.types.attrsOf registry.type);
-      default = { };
-      description = ''
-        Lazily collected fleet-visible registry entries, nested by host and entry name.
-      '';
-    };
-
-  mkRegistry =
-    path:
-    let
-      evaluated = lib.evalModules {
-        specialArgs.lib = registryLib;
-        modules = [
-          registryDefinitionModule
-          path
-        ];
-      };
-    in
-    {
-      inherit (evaluated.config) type replicate checks;
-    };
-
-  definitions =
-    lib.mapAttrs'
-      (
-        name: _type:
-        let
-          path = root + "/${name}";
-        in
-        lib.nameValuePair (registryName name) (mkRegistry path)
-      )
-      (
-        lib.filterAttrs (name: type: type == "regular" && lib.hasSuffix ".nix" name) (builtins.readDir root)
-      );
-
-  flattenRegistryEntries =
-    registryName: data:
-    lib.concatLists (
-      lib.mapAttrsToList (
-        host: entries:
-        lib.mapAttrsToList (entry: value: {
-          path = "registry.${registryName}.${host}.${entry}";
-          inherit host entry value;
-        }) entries
-      ) data
-    );
-
-  rawDeclarations =
-    registryName: hosts:
-    lib.mapAttrs (_hostName: host: host.config.registry.${registryName} or { }) hosts;
-
-  replicatedEntries =
-    registryName: raw:
-    let
-      entries = lib.concatLists (
-        lib.concatLists (
-          lib.mapAttrsToList (
-            _evalHost: hostDeclarations:
-            lib.mapAttrsToList (
-              hostName: declarations:
-              lib.mapAttrsToList (entryName: value: {
-                path = "registry.${registryName}.${hostName}.${entryName}";
-                inherit entryName value;
-              }) declarations
-            ) hostDeclarations
-          ) raw
-        )
-      );
-    in
-    lib.foldl' (
-      acc: entry:
-      if lib.hasAttr entry.entryName acc then
-        if acc.${entry.entryName}.value == entry.value then
-          acc
-        else
-          throw "conflicting replicated registry entry ${entry.path} does not match ${acc.${entry.entryName}.path}"
-      else
-        acc
-        // {
-          ${entry.entryName} = entry;
-        }
-    ) { } entries;
-
-  replicatedData =
-    registryName: hosts: raw:
-    let
-      entries = lib.mapAttrs (_entryName: entry: entry.value) (replicatedEntries registryName raw);
-    in
-    lib.mapAttrs (_hostName: _host: entries) hosts;
-
-  validationAssertions =
-    data:
-    lib.concatLists (
-      lib.mapAttrsToList (
-        registryName: registry:
-        let
-          entries = flattenRegistryEntries registryName data.${registryName};
-        in
-        map (check: {
-          assertion = check.assertion entries;
-          inherit (check) message;
-        }) registry.checks
-      ) definitions
-    );
-
-  assertValid =
-    data:
-    let
-      assertions = validationAssertions data;
-      failures = lib.filter (assertion: !assertion.assertion) assertions;
-    in
-    assert lib.assertMsg (lib.all (assertion: assertion.assertion) assertions) (
-      lib.concatMapStringsSep "\n" (assertion: assertion.message) failures
-    );
-    data;
-
-  join =
-    registry: host: entry:
-    lib.filterAttrs (_name: value: value != null) (
-      lib.mapAttrs (
-        registryName: _registry: (registry.${registryName}.${host} or { }).${entry} or null
-      ) definitions
-    );
-
-  collectData =
-    { hosts }:
-    let
-      raw = lib.mapAttrs (registryName: _registry: rawDeclarations registryName hosts) definitions;
-      data = lib.mapAttrs (
-        registryName: registry:
-        if registry.replicate or false then
-          replicatedData registryName hosts raw.${registryName}
-        else
-          lib.mapAttrs (hostName: host: host.config.registry.${registryName}.${hostName} or { }) hosts
-      ) definitions;
-    in
-    assertValid data;
-
-  withOperations =
-    registry:
-    registry
-    // {
-      join = host: entry: join registry host entry;
-    };
 in
 {
   types = lib.mapAttrs (_name: definition: definition.type) definitions;
@@ -217,7 +32,11 @@ in
     options.registry = lib.mapAttrs (_name: registryOption) definitions;
   };
 
-  collected = withOperations (collectData {
-    inherit hosts;
-  });
+  collected = operations.withOperations (
+    validation.assertValid (
+      collection.collectData {
+        inherit hosts;
+      }
+    )
+  );
 }

src/dotfiles/registry/collect.nix

@@ -0,0 +1,67 @@
+{ definitions, lib }:
+let
+  rawDeclarations =
+    registryName: hosts:
+    lib.mapAttrs (_hostName: host: host.config.registry.${registryName} or { }) hosts;
+
+  replicatedEntries =
+    registryName: raw:
+    let
+      entries = lib.concatLists (
+        lib.concatLists (
+          lib.mapAttrsToList (
+            _evalHost: hostDeclarations:
+            lib.mapAttrsToList (
+              hostName: declarations:
+              lib.mapAttrsToList (entryName: value: {
+                path = "registry.${registryName}.${hostName}.${entryName}";
+                inherit entryName value;
+              }) declarations
+            ) hostDeclarations
+          ) raw
+        )
+      );
+    in
+    lib.foldl' (
+      acc: entry:
+      if lib.hasAttr entry.entryName acc then
+        if acc.${entry.entryName}.value == entry.value then
+          acc
+        else
+          throw "conflicting replicated registry entry ${entry.path} does not match ${acc.${entry.entryName}.path}"
+      else
+        acc
+        // {
+          ${entry.entryName} = entry;
+        }
+    ) { } entries;
+
+  replicatedData =
+    registryName: hosts: raw:
+    let
+      entries = lib.mapAttrs (_entryName: entry: entry.value) (replicatedEntries registryName raw);
+    in
+    lib.mapAttrs (_hostName: _host: entries) hosts;
+
+  collectData =
+    { hosts }:
+    let
+      raw = lib.mapAttrs (registryName: _registry: rawDeclarations registryName hosts) definitions;
+      data = lib.mapAttrs (
+        registryName: registry:
+        if registry.replicate or false then
+          replicatedData registryName hosts raw.${registryName}
+        else
+          lib.mapAttrs (hostName: host: host.config.registry.${registryName}.${hostName} or { }) hosts
+      ) definitions;
+    in
+    data;
+in
+{
+  inherit
+    collectData
+    rawDeclarations
+    replicatedData
+    replicatedEntries
+    ;
+}

src/dotfiles/registry/definition-module.nix

@@ -0,0 +1,66 @@
+{ lib }:
+let
+  checkType = lib.types.submodule {
+    options = {
+      assertion = lib.mkOption {
+        type = lib.types.functionTo lib.types.bool;
+        description = ''
+          Predicate run against this registry's flattened collected entries.
+        '';
+      };
+
+      message = lib.mkOption {
+        type = lib.types.str;
+        description = ''
+          Error message shown when this registry validation check fails.
+        '';
+      };
+    };
+  };
+
+  predicates = {
+    uniqueValue =
+      value: entries: builtins.length (lib.unique (map value entries)) == builtins.length entries;
+  };
+
+  registryLib = lib // {
+    registry = (lib.registry or { }) // {
+      inherit predicates;
+    };
+  };
+
+  registryDefinitionModule = {
+    options = {
+      type = lib.mkOption {
+        type = lib.types.raw;
+        description = ''
+          NixOS option type for one registry entry.
+        '';
+      };
+
+      replicate = lib.mkOption {
+        type = lib.types.bool;
+        default = false;
+        description = ''
+          Whether collected entries are merged and published under every host key.
+        '';
+      };
+
+      checks = lib.mkOption {
+        type = lib.types.listOf checkType;
+        default = [ ];
+        description = ''
+          Validation checks for this registry's flattened collected entries.
+        '';
+      };
+    };
+  };
+in
+{
+  inherit
+    checkType
+    predicates
+    registryDefinitionModule
+    registryLib
+    ;
+}

src/dotfiles/registry/definitions.nix

@@ -0,0 +1,35 @@
+{
+  lib,
+  registryDefinitionModule,
+  registryLib,
+  root,
+}:
+let
+  registryName = fileName: lib.removeSuffix ".nix" fileName;
+
+  mkRegistry =
+    path:
+    let
+      evaluated = lib.evalModules {
+        specialArgs.lib = registryLib;
+        modules = [
+          registryDefinitionModule
+          path
+        ];
+      };
+    in
+    {
+      inherit (evaluated.config) type replicate checks;
+    };
+in
+lib.mapAttrs'
+  (
+    name: _type:
+    let
+      path = root + "/${name}";
+    in
+    lib.nameValuePair (registryName name) (mkRegistry path)
+  )
+  (
+    lib.filterAttrs (name: type: type == "regular" && lib.hasSuffix ".nix" name) (builtins.readDir root)
+  )

src/dotfiles/registry/operations.nix

@@ -0,0 +1,20 @@
+{ definitions, lib }:
+let
+  join =
+    registry: host: entry:
+    lib.filterAttrs (_name: value: value != null) (
+      lib.mapAttrs (
+        registryName: _registry: (registry.${registryName}.${host} or { }).${entry} or null
+      ) definitions
+    );
+
+  withOperations =
+    registry:
+    registry
+    // {
+      join = host: entry: join registry host entry;
+    };
+in
+{
+  inherit join withOperations;
+}

src/dotfiles/registry/options.nix

@@ -0,0 +1,9 @@
+{ lib }:
+registry:
+lib.mkOption {
+  type = lib.types.attrsOf (lib.types.attrsOf registry.type);
+  default = { };
+  description = ''
+    Lazily collected fleet-visible registry entries, nested by host and entry name.
+  '';
+}

src/dotfiles/registry/validation.nix

@@ -0,0 +1,47 @@
+{ definitions, lib }:
+let
+  flattenRegistryEntries =
+    registryName: data:
+    lib.concatLists (
+      lib.mapAttrsToList (
+        host: entries:
+        lib.mapAttrsToList (entry: value: {
+          path = "registry.${registryName}.${host}.${entry}";
+          inherit host entry value;
+        }) entries
+      ) data
+    );
+
+  validationAssertions =
+    data:
+    lib.concatLists (
+      lib.mapAttrsToList (
+        registryName: registry:
+        let
+          entries = flattenRegistryEntries registryName data.${registryName};
+        in
+        map (check: {
+          assertion = check.assertion entries;
+          inherit (check) message;
+        }) registry.checks
+      ) definitions
+    );
+
+  assertValid =
+    data:
+    let
+      assertions = validationAssertions data;
+      failures = lib.filter (assertion: !assertion.assertion) assertions;
+    in
+    assert lib.assertMsg (lib.all (assertion: assertion.assertion) assertions) (
+      lib.concatMapStringsSep "\n" (assertion: assertion.message) failures
+    );
+    data;
+in
+{
+  inherit
+    assertValid
+    flattenRegistryEntries
+    validationAssertions
+    ;
+}

statix.toml

@@ -1,3 +0,0 @@
-disabled = [
-  "repeated_keys",
-]