From 0ea3b1bbc7b49d62a234024453eb10d950c1d354 Mon Sep 17 00:00:00 2001
From: ayumi-signal <143036029+ayumi-signal@users.noreply.github.com>
Date: Wed, 13 May 2026 10:21:25 -0700
Subject: [PATCH] Add experimental support for building Linux ARM64

Co-authored-by: trevor-signal <131492920+trevor-signal@users.noreply.github.com>
---
 package.json                             |  5 ++++-
 reproducible-builds/build.sh             |  4 +++-
 reproducible-builds/docker-entrypoint.sh |  4 ++--
 scripts/prepare_linux_build.mjs          | 18 ++++++++++++++++--
 ts/updater/common.main.ts                |  4 ++++
 5 files changed, 29 insertions(+), 6 deletions(-)

diff --git a/package.json b/package.json
index 9a335a423..00bc2d70b 100644
--- a/package.json
+++ b/package.json
@@ -525,7 +525,10 @@
       },
       "artifactName": "${name}_${version}_${arch}.${ext}",
       "target": [
-        "deb"
+        {
+          "target": "deb",
+          "arch": "x64"
+        }
       ],
       "icon": "build/icons/png",
       "publish": [
diff --git a/reproducible-builds/build.sh b/reproducible-builds/build.sh
index 40b802f9c..47bab78d6 100755
--- a/reproducible-builds/build.sh
+++ b/reproducible-builds/build.sh
@@ -7,7 +7,8 @@
 # Env vars:
 # SOURCE_DATE_EPOCH: Build timestamp override. Defaults to latest git commit or 1.
 # SKIP_DOCKER_BUILD: To support docker build cache during actions.
-# BUILD_TARGETS: Override build targets. Empty default results in deb.
+# BUILD_TARGETS: Override build targets. Empty default results in deb. Comma separated list.
+# BUILD_ARCH: Override build architectures. Empty default results in x64. Comma separated list.
 
 # Examples:
 # ./build.sh public
@@ -54,4 +55,5 @@ docker run --rm \
   -e PNPM_HOME=/tmp/.pnpm-home \
   -e SOURCE_DATE_EPOCH=$source_date_epoch \
   -e BUILD_TARGETS=$BUILD_TARGETS \
+  -e BUILD_ARCH=$BUILD_ARCH \
   signal-desktop $1
diff --git a/reproducible-builds/docker-entrypoint.sh b/reproducible-builds/docker-entrypoint.sh
index 118ef910c..2151f68df 100644
--- a/reproducible-builds/docker-entrypoint.sh
+++ b/reproducible-builds/docker-entrypoint.sh
@@ -66,8 +66,8 @@ else
   exit 1
 fi
 
-if [ "${BUILD_TARGETS}" != "" ]; then
-  pnpm run prepare-linux-build $BUILD_TARGETS
+if [ "${BUILD_TARGETS}" != "" ] || [ "${BUILD_ARCH}" != "" ]; then
+  pnpm run prepare-linux-build "$BUILD_TARGETS" "$BUILD_ARCH"
 fi
 
 pnpm run build-linux
diff --git a/scripts/prepare_linux_build.mjs b/scripts/prepare_linux_build.mjs
index 5434c2831..4cd497b11 100644
--- a/scripts/prepare_linux_build.mjs
+++ b/scripts/prepare_linux_build.mjs
@@ -6,8 +6,9 @@ import _ from 'lodash';
 import packageJson from '../package.json' with { type: 'json' };
 
 const TARGETS = new Set(['appimage', 'deb']);
+const ARCHITECTURES = new Set(['arm64', 'x64']);
 
-const targets = (process.argv[2] || '').split(',');
+const targets = (process.argv[2] || 'deb').split(',');
 if (
   targets.length === 0 ||
   !targets.every(target => TARGETS.has(target.toLowerCase()))
@@ -18,11 +19,24 @@ if (
   process.exit(1);
 }
 
+const archs = (process.argv[3] || 'x64').split(',');
+if (
+  archs.length === 0 ||
+  !archs.every(arch => ARCHITECTURES.has(arch.toLowerCase()))
+) {
+  console.error(
+    `Invalid linux architectures ${archs.join(', ')}. Valid options: ${[...ARCHITECTURES].join(', ')}`
+  );
+  process.exit(1);
+}
+
 console.log('prepare_linux_build: updating package.json');
 
 // ------
 
-_.set(packageJson, 'build.linux.target', targets);
+const targetsWithArch = _.map(targets, target => ({ target, arch: archs }));
+
+_.set(packageJson, 'build.linux.target', targetsWithArch);
 
 // -------
 
diff --git a/ts/updater/common.main.ts b/ts/updater/common.main.ts
index dbbe582c5..1956c02a2 100644
--- a/ts/updater/common.main.ts
+++ b/ts/updater/common.main.ts
@@ -997,6 +997,10 @@ function getUpdatesFileName(): string {
   }
 
   if (process.platform === 'linux') {
+    if (process.arch === 'arm64') {
+      return `${prefix}-linux-arm64.yml`;
+    }
+
     return `${prefix}-linux.yml`;
   }