From ebd329f8bc080bbc64fbea3167501636c94a2382 Mon Sep 17 00:00:00 2001
From: BREW <81044362+b-re-w@users.noreply.github.com>
Date: Sat, 3 Oct 2026 15:25:53 +0900
Subject: [PATCH] Chore: Install CPU torch wheels on Windows and Linux

The engine runs on CPU, but Windows took torch from the CUDA 12.8 index
and Linux took PyPI's CUDA build: several GB of downloads with no use.
Both now use the PyTorch CPU index; macOS keeps the PyPI default. CUDA
returns in M4 as a cuda extra. AGENTS.md also notes that executable bits
must be set with git update-index --chmod=+x (core.fileMode=false).
---
 AGENTS.md      | 8 ++++++--
 pyproject.toml | 8 +++++---
 2 files changed, 11 insertions(+), 5 deletions(-)

diff --git a/AGENTS.md b/AGENTS.md
index 264066d9..f6259a70 100644
--- a/AGENTS.md
+++ b/AGENTS.md
@@ -235,14 +235,18 @@ report it as coverage. New behaviour starts with a real failing test (rule 5).
 ## 15. Dependencies
 
 - `torch` and `torchnative` are mutually exclusive extras (torchnative replaces `import torch`).
-  Do not add a version pin to `torch`; the Windows wheels come from the CUDA index configured under
-  `[tool.uv.sources]`.
+  Do not add a version pin to `torch`; on Windows and Linux it comes from the PyTorch CPU index
+  configured under `[tool.uv.sources]` (the engine runs on CPU; CUDA returns in M4 as a `cuda` extra).
 - The engine uses only the public `torch` / `transformers` API. Custom kernels cannot be registered
   from Gemstone (`torch.library` is a no-op on torchnative); they belong in torchnative.
 - Kotlin and library versions live in `gradle/libs.versions.toml`. Bump them there, not inline.
 
 ## 16. Line endings and encoding
 
+This repository's git config has `core.fileMode=false`, so `chmod +x` is not recorded: set the
+executable bit of a tracked script with `git update-index --chmod=+x <file>` (`gradlew` and
+`tools/*.sh` were affected).
+
 Write every file as UTF-8 with LF line endings. Some checkouts of this repository have had files
 converted to CRLF by an editor; do not mass-convert files you were not asked to touch, because the
 whole-file diff hides real changes. The repository's `.gitattributes` fixes LF (only `.bat`, `.cmd` and `.ps1` are CRLF), so new
diff --git a/pyproject.toml b/pyproject.toml
index df344a57..3d3d9436 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -48,15 +48,17 @@ conflicts = [
 prerelease = "if-necessary"
 
 
+# The engine runs on CPU (CUDA is planned for M4 as a `cuda` extra), so Windows and Linux take the
+# PyTorch CPU wheels instead of multi-GB CUDA builds; macOS uses the PyPI default (CPU/MPS).
 [tool.uv.sources]
 torch = [
-    { index = "pytorch-windows", marker = "platform_system == 'Windows'" },
+    { index = "pytorch-cpu", marker = "platform_system == 'Windows' or platform_system == 'Linux'" },
 ]
 
 
 [[tool.uv.index]]
-name = "pytorch-windows"
-url = "https://download.pytorch.org/whl/cu128"
+name = "pytorch-cpu"
+url = "https://download.pytorch.org/whl/cpu"
 explicit = true