From 263ee6781bb15e5fc41f99ee234074a876f8bb68 Mon Sep 17 00:00:00 2001
From: Luke Curley <432854+kixelated@users.noreply.github.com>
Date: Sat, 7 Nov 2026 11:26:48 -0800
Subject: [PATCH 1/2] chore(quest): claim quest/m0/swift-guard.md

Quest-Claim: d62505b09a42c245

From 35ec82a748b283fa09e946ab63705e57bc48ec49 Mon Sep 17 00:00:00 2001
From: Luke Curley <432854+kixelated@users.noreply.github.com>
Date: Sat, 7 Nov 2026 11:31:27 -0800
Subject: [PATCH 2/2] fix(nix): leave out Swift where its compiler is broken

nixpkgs' `swift` wrapper copies only `platforms` and `badPlatforms` from
`swiftc`, so `swift.meta.broken` is always false and the default shell
pulled in swiftc 6.3.3 on aarch64-linux, which nixpkgs refuses to evaluate.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 flake.nix               |  3 ++-
 quest/m0/README.md      |  1 -
 quest/m0/swift-guard.md | 23 -----------------------
 3 files changed, 2 insertions(+), 25 deletions(-)
 delete mode 100644 quest/m0/swift-guard.md

diff --git a/flake.nix b/flake.nix
index 305c25751..3faa5d820 100644
--- a/flake.nix
+++ b/flake.nix
@@ -308,7 +308,8 @@
               dart
             ];
             # ... and its generated Swift, where nixpkgs builds Swift: not on aarch64-linux.
-            nativeBuildInputs = pkgs.lib.optional (!pkgs.swift.meta.broken) pkgs.swift;
+            # The `swift` wrapper doesn't copy its compiler's `broken`, so ask the compiler.
+            nativeBuildInputs = pkgs.lib.optional (!pkgs.swift.swiftc.meta.broken) pkgs.swift;
             RUST2_TS_TOOLCHAIN = tsToolchain;
             RUST2_TS_SYSROOT = rust2-ts-std;
             KOTLINX_COROUTINES = "${kotlinx-coroutines}";
diff --git a/quest/m0/README.md b/quest/m0/README.md
index 08736f0d5..fa2096325 100644
--- a/quest/m0/README.md
+++ b/quest/m0/README.md
@@ -6,5 +6,4 @@ Urgent fixes to anything a consumer already depends on.
 
 ## Required
 
-- [Leave out a broken Swift on aarch64](/quest/m0/swift-guard.md) - the default dev shell evaluates on aarch64-linux, so the nightly's aarch64 jobs pass
 - [Checks at moq's cost](/quest/m0/checks/README.md) - `just ci` selects by the diff, builds warm, and runs the differential optimized, with a nightly full `just gate`
diff --git a/quest/m0/swift-guard.md b/quest/m0/swift-guard.md
deleted file mode 100644
index 63c48b2a1..000000000
--- a/quest/m0/swift-guard.md
+++ /dev/null
@@ -1,23 +0,0 @@
-# [XS] Leave out a broken Swift on aarch64
-
-## Goal
-
-The default dev shell leaves Swift out wherever nixpkgs marks `swiftc` broken, so it
-evaluates on aarch64-linux and the nightly's aarch64 jobs pass again. Today they have
-failed since 2026-10-29 on `Refusing to evaluate package 'swiftc-6.3.3'`.
-
-## Plan
-
-The guard `!pkgs.swift.meta.broken` (`flake.nix`, the default shell's
-`nativeBuildInputs`) is always true: nixpkgs' `swift` wrapper copies only `platforms` and
-`badPlatforms` from `swiftc`, not `broken`,
-so the shell still pulls in the broken compiler. Guard on `pkgs.swiftc.meta.broken`
-instead. Found while reviewing [#617](https://github.com/moq-dev/rust2/pull/617), whose
-nixpkgs bump does not change it. The guard came in with the comment's "not on
-aarch64-linux" note; name its PR under `## Caused by`.
-
-[Swift 6.4 in nixpkgs-unstable](/quest/m2/uniffi-swift-arm.md) still restores Swift on
-aarch64 once nixpkgs ships it.
-
-Decided with the maintainer on 2026-11-07: ✅ m0 (rejected: fold into the m2 waiting
-quest, drop), since a red nightly hides new failures.