chore(s133): the Linux Burrito bundle leaves exla out

mix.exs

@@ -60,8 +60,9 @@ defmodule Trinity.MixProject do
       desktop: [
         steps: [:assemble, &Burrito.wrap/1],
         # Slice 032: exla in the release, loaded and not started (see `exla_deps/0`); on a
-        # Windows host it is not declared at all.
-        applications: exla_release_applications(),
+        # Windows host it is not declared at all. Slice 133: not in the Linux bundle either
+        # (`desktop_release_applications/1`).
+        applications: desktop_release_applications(System.get_env("BURRITO_TARGET")),
         burrito: [
           targets: [
             linux_x86_64: [os: :linux, cpu: :x86_64],
@@ -126,6 +127,19 @@ defmodule Trinity.MixProject do
     end
   end
 
+  @doc """
+  The desktop release's applications for one Burrito target (slice 133, AC12). The Linux
+  bundle leaves exla out: its NIF never loaded there (Burrito's musl ERTS against a glibc
+  `.so`, the `__libc_single_threaded` failure above), so the bundle already ran with the local
+  embedder off and the Elixir scorer in `Trinity.Memory.VectorStores.Brute`, and the 68.7 MB
+  it carried was dead weight (slice 032's PROOF). macOS keeps it until slice 133's eval; the
+  headless release keeps `exla_release_applications/0`. Public only so a test can call it.
+  `package.yml` sets `BURRITO_TARGET` per job; a local `mix release desktop` without it builds
+  every target with what the host declares, as before.
+  """
+  def desktop_release_applications("linux_x86_64"), do: []
+  def desktop_release_applications(_target), do: exla_release_applications()
+
   defp exla_deps do
     case :os.type() do
       {:win32, _} -> []

test/release_composition_test.exs

@@ -0,0 +1,31 @@
+# SPDX-FileCopyrightText: Sudo Apt Holdings LLC
+# SPDX-License-Identifier: Apache-2.0
+defmodule ReleaseCompositionTest do
+  @moduledoc """
+  Slice 133, AC12. The Linux Burrito bundle carries no exla. The release's applications are
+  computed in `mix.exs`, so this asserts on the function `releases/0` calls for the desktop
+  release, for each target `package.yml` builds. The artifact's size and its
+  `TRINITY_SMOKE_EXLA` line are the package run's half and are cited in the proof.
+  """
+  use ExUnit.Case, async: true
+
+  test "the Linux bundle leaves exla out" do
+    linux = Trinity.MixProject.desktop_release_applications("linux_x86_64")
+    refute Keyword.has_key?(linux, :exla)
+  end
+
+  test "macOS and Windows bundles, and a build with no target, keep what the host declares" do
+    for target <- ["macos_aarch64", "windows_x86_64", nil] do
+      assert Trinity.MixProject.desktop_release_applications(target) == headless()
+    end
+  end
+
+  test "the headless release still carries exla where the host declares it" do
+    case :os.type() do
+      {:win32, _} -> assert headless() == []
+      _ -> assert headless()[:exla] == :load
+    end
+  end
+
+  defp headless, do: Trinity.MixProject.project()[:releases][:headless][:applications]
+end