TypesettingTools · CoffeeFlux · Aug 3, 2026 · Aug 3, 2026 · Aug 4, 2026
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
@@ -20,6 +20,9 @@ jobs:
           - name: Windows MSVC Release
             os: windows-latest
             msvc: true
+            arch: x64
+            vs_component: Microsoft.VisualStudio.Component.VC.Tools.x86.x64
+            package: true
             devenv: |
               Import-Module "$env:VS\Common7\Tools\Microsoft.VisualStudio.DevShell.dll"
               Enter-VsDevShell -VsInstallPath $env:VS -SkipAutomaticLocation -DevCmdArguments "-arch=x64 -host_arch=x64"
@@ -38,6 +41,31 @@ jobs:
               -Dfribidi:tests=false
               -Dfribidi:docs=false
               -Dlibass:fontconfig=disabled
+          - name: Windows ARM64 MSVC Release
+            os: windows-11-arm
+            msvc: true
+            arch: arm64
+            vs_component: Microsoft.VisualStudio.Component.VC.Tools.ARM64
+            package: true
+            devenv: |
+              Import-Module "$env:VS\Common7\Tools\Microsoft.VisualStudio.DevShell.dll"
+              Enter-VsDevShell -VsInstallPath $env:VS -SkipAutomaticLocation -DevCmdArguments "-arch=arm64 -host_arch=arm64"
+            buildtype: release
+            args: >-
+              -Ddefault_library=static
+              --force-fallback-for=zlib,harfbuzz,freetype2,fribidi,libpng
+              -Dfallback_nasm=true
+              -Dfreetype2:harfbuzz=disabled
+              -Dharfbuzz:freetype=disabled
+              -Dharfbuzz:cairo=disabled
+              -Dharfbuzz:glib=disabled
+              -Dharfbuzz:gobject=disabled
+              -Dharfbuzz:tests=disabled
+              -Dharfbuzz:docs=disabled
+              -Dfribidi:tests=false
+              -Dfribidi:docs=false
+              -Dlibass:fontconfig=disabled
+              -Dcsri=disabled
           #- {
           #  name: Windows MinGW,
           #  os: windows-latest,
@@ -92,22 +120,22 @@ jobs:
       - name: Setup Meson
         run: |
           python -m pip install --upgrade pip setuptools
-          pip install meson
+          pip install meson ninja
 
         # Taken from https://github.com/libass/libass/blob/0.17.5/.github/workflows/meson.yml#L118-L125
       - name: Find Visual Studio
         if: matrix.config.msvc
         run: |
           $vswhere = "${env:ProgramFiles(x86)}\Microsoft Visual Studio\Installer\vswhere.exe"
-          $vsPath = & $vswhere -latest -products * -requires Microsoft.VisualStudio.Component.VC.Tools.x86.x64 -property installationPath
+          $vsPath = & $vswhere -latest -products * -requires ${{ matrix.config.vs_component }} -property installationPath
           if (-not $vsPath) { throw "Could not find a Visual Studio installation" }
           "VS=$vsPath"
           "VS=$vsPath" >> $env:GITHUB_ENV
 
       - name: Install dependencies (Windows)
-        if: matrix.config.os == 'windows-latest'
+        if: startsWith(matrix.config.os, 'windows-')
         run: |
-          choco install ninja innosetup
+          if ('${{ matrix.config.package }}' -eq 'true') { choco install innosetup }
 
           $moonscripturl = "https://github.com/leafo/moonscript/releases/download/v0.6.0/moonscript-v0.6.0-windows-x86_64.zip"
           mkdir moonscript
@@ -146,6 +174,23 @@ jobs:
           sudo apt-get install -y lua5.1 liblua5.1-0-dev luarocks
           sudo luarocks --lua-version=5.1 install busted
 
+      # dav1d's ARM assembly uses GNU syntax, which MSVC's armasm64 cannot
+      # consume directly. gas-preprocessor translates it during the build.
+      - name: Checkout gas-preprocessor (Windows ARM64)
+        if: matrix.config.msvc && matrix.config.arch == 'arm64'
+        uses: actions/checkout@v6
+        with:
+          repository: FFmpeg/gas-preprocessor
+          ref: ac1836309c2e77023c228b7184485597286289d3
+          path: gas-preprocessor
+
+      - name: Setup gas-preprocessor (Windows ARM64)
+        if: matrix.config.msvc && matrix.config.arch == 'arm64'
+        run: |
+          $gaspp = (Resolve-Path gas-preprocessor).Path
+          $gaspp | Out-File -FilePath $env:GITHUB_PATH -Encoding utf8 -Append
+          perl -c "$gaspp\gas-preprocessor.pl"
+
       - name: Configure
         run: |
           ${{ matrix.config.devenv }}
@@ -170,33 +215,33 @@ jobs:
 
       # Windows artifacts
       - name: Generate Windows installer
-        if: matrix.config.os == 'windows-latest'
+        if: matrix.config.package
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
           ${{ matrix.config.devenv }}
           meson compile win-installer -C build
 
       - name: Generate Windows portable installer
-        if: matrix.config.os == 'windows-latest'
+        if: matrix.config.package
         run: |
           ${{ matrix.config.devenv }}
           cd build && ninja win-portable
 
       - name: Upload artifacts - win_installer
         uses: actions/upload-artifact@v6
-        if: matrix.config.os == 'windows-latest'
+        if: matrix.config.package
         with:
           name: ${{ matrix.config.name }} - installer
           path: build/Aegisub-*.exe
           if-no-files-found: error
 
       - name: Upload artifacts - portable.zip
         uses: actions/upload-artifact@v6
-        if: matrix.config.os == 'windows-latest'
+        if: matrix.config.package
         with:
           name: ${{ matrix.config.name }} - portable
-          path: build/aegisub-portable-64.zip
+          path: build/aegisub-portable-${{ matrix.config.arch }}.zip
 
       # macOS artifacts
       - name: Generate macOS installer

diff --git a/packages/meson.build b/packages/meson.build
@@ -1,16 +1,17 @@
 conf_pkg = configuration_data()
 
 if host_machine.system() == 'windows'
+    package_arch = host_machine.cpu_family() == 'aarch64' ? 'arm64' : 'x64'
     installer_setup = [powershell_exe,
                        '-ExecutionPolicy', 'Bypass',
                        '-File', meson.project_source_root() / 'tools/win-installer-setup.ps1']
     run_target('win-installer',
-               command: [installer_setup, meson.project_build_root(), meson.project_source_root()])
+               command: [installer_setup, meson.project_build_root(), meson.project_source_root(), package_arch])
 
     portable_setup = [powershell_exe,
                       '-ExecutionPolicy', 'Bypass',
                       '-File', meson.project_source_root() / 'packages/win_installer/portable/create-portable.ps1']
-    run_target('win-portable', command: [portable_setup, meson.project_build_root(), meson.project_source_root()])
+    run_target('win-portable', command: [portable_setup, meson.project_build_root(), meson.project_source_root(), package_arch])
 elif host_machine.system() == 'darwin'
     fontconfig_conf = run_command('pkg-config', '--variable=confdir', 'fontconfig').stdout().strip()
     bundle_app_sh = find_program(meson.project_source_root() / 'tools/osx-bundle.sh')

diff --git a/packages/win_installer/aegisub3.iss b/packages/win_installer/aegisub3.iss
@@ -1,4 +1,8 @@
-#define ARCH 64
+#ifdef ARM64
+#define ARCH "arm64"
+#else
+#define ARCH "x64"
+#endif
 
 #include "fragment_setupbase.iss"
 #include "fragment_strings.iss"
@@ -7,8 +11,13 @@
 AppID={{24BC8B57-716C-444F-B46B-A3349B9164C5}
 DefaultDirName={commonpf}\Aegisub
 PrivilegesRequired=poweruser
+#ifdef ARM64
+ArchitecturesInstallIn64BitMode=arm64
+ArchitecturesAllowed=arm64
+#else
 ArchitecturesInstallIn64BitMode=x64compatible
 ArchitecturesAllowed=x64compatible
+#endif
 
 #include "fragment_mainprogram.iss"
 #include "fragment_associations.iss"

diff --git a/packages/win_installer/fragment_codecs.iss b/packages/win_installer/fragment_codecs.iss
@@ -4,4 +4,6 @@
 ; DestDir: {app}; Source: {#DEPS_DIR}\AvisynthPlus64\x64\Output\AviSynth.dll; Flags: ignoreversion; Components: main
 ; DestDir: {app}; Source: {#DEPS_DIR}\AvisynthPlus64\x64\Output\plugins\DirectShowSource.dll; Flags: ignoreversion; Components: main
 ; VSFilter
+#ifndef ARM64
 DestDir: {app}\csri; Source: {#DEPS_DIR}\VSFilter\x64\VSFilter.dll; Flags: ignoreversion; Components: main
+#endif
diff --git a/packages/win_installer/fragment_runtimes.iss b/packages/win_installer/fragment_runtimes.iss
@@ -1,7 +1,7 @@
 ; This file implements checking for and installing runtime libraries for Aegisub
 
 [Files]
-DestDir: {tmp}; Source: "{#DEPS_DIR}\VC_redist\VC_redist.x{#ARCH}.exe"; Flags: nocompression deleteafterinstall
+DestDir: {tmp}; Source: "{#DEPS_DIR}\VC_redist\VC_redist.{#ARCH}.exe"; Flags: nocompression deleteafterinstall
 
 [Run]
-Filename: {tmp}\VC_redist.x{#ARCH}.exe; StatusMsg: {cm:InstallRuntime}; Parameters: "/install /quiet /norestart"
+Filename: {tmp}\VC_redist.{#ARCH}.exe; StatusMsg: {cm:InstallRuntime}; Parameters: "/install /quiet /norestart"
diff --git a/packages/win_installer/fragment_setupbase.iss b/packages/win_installer/fragment_setupbase.iss
@@ -35,7 +35,11 @@ UninstallDisplayIcon={app}\aegisub.exe
 WizardImageFile={#INSTALLER_DIR}\welcome-large.bmp
 WizardSmallImageFile={#INSTALLER_DIR}\aegisub-large.bmp
 
+#ifdef ARM64
+OutputBaseFilename=Aegisub-{#BUILD_GIT_VERSION_STRING}-arm64
+#else
 OutputBaseFilename=Aegisub-{#BUILD_GIT_VERSION_STRING}
+#endif
 VersionInfoDescription=Aegisub {#BUILD_GIT_VERSION_STRING}
 
 [Languages]

diff --git a/packages/win_installer/portable/create-portable.ps1 b/packages/win_installer/portable/create-portable.ps1
@@ -6,7 +6,10 @@ param (
     [string]$BuildRoot,
     [Parameter(Position = 1, Mandatory = $true)]
     [ValidateNotNullOrEmpty()]
-    [string]$SourceRoot
+    [string]$SourceRoot,
+    [Parameter(Position = 2, Mandatory = $true)]
+    [ValidateSet('x64', 'arm64')]
+    [string]$Architecture
 )
 
 $ErrorActionPreference = 'Stop'
@@ -38,7 +41,7 @@ Write-Host "SOURCE_ROOT=$SourceRoot"
 $InstallerDir = Join-Path $BuildRoot "install"
 $InstallerDepsDir = Join-Path $BuildRoot "installer-deps"
 $PortableOutputDir = Join-Path $BuildRoot "aegisub-portable"
-$PortableZipPath = Join-Path $BuildRoot "aegisub-portable-64.zip"
+$PortableZipPath = Join-Path $BuildRoot "aegisub-portable-$Architecture.zip"
 
 Write-Step 'Removing previous output'
 Remove-Item -LiteralPath $PortableOutputDir -Force -Recurse -ErrorAction SilentlyContinue
@@ -63,11 +66,16 @@ Copy-ToDirectory $InstallerDepsDir\dictionaries\en_US.dic  $PortableOutputDir\di
 # Copy-ToDirectory $InstallerDepsDir\AvisynthPlus64\x64\Output\AviSynth.dll  $PortableOutputDir
 # Copy-ToDirectory $InstallerDepsDir\AvisynthPlus64\x64\Output\plugins\DirectShowSource.dll  $PortableOutputDir
 
-Write-Step 'Copying VSFilter'
-Copy-ToDirectory $InstallerDepsDir\VSFilter\x64\VSFilter.dll  $PortableOutputDir\csri
+if ($Architecture -eq 'x64') {
+    Write-Step 'Copying VSFilter'
+    Copy-ToDirectory $InstallerDepsDir\VSFilter\x64\VSFilter.dll $PortableOutputDir\csri
+}
+else {
+    Write-Step 'Skipping VSFilter (not available for ARM64)'
+}
 
 Write-Step 'Copying VC++ runtime'
-Copy-ToDirectory $InstallerDepsDir\VC_redist\VC_redist.x64.exe $PortableOutputDir\Microsoft.CRT
+Copy-ToDirectory (Join-Path $InstallerDepsDir "VC_redist\VC_redist.$Architecture.exe") $PortableOutputDir\Microsoft.CRT
 
 Write-Step 'Copying automation'
 Copy-ToDirectory "$InstallerDir\share\aegisub\automation\*"  "$PortableOutputDir\automation\"  -Recurse

diff --git a/tools/win-installer-setup.ps1 b/tools/win-installer-setup.ps1
@@ -7,6 +7,9 @@ param (
   [Parameter(Position = 1, Mandatory = $true)]
   [ValidateNotNullOrEmpty()]
   [string]$SourceRoot,
+  [Parameter(Position = 2, Mandatory = $true)]
+  [ValidateSet('x64', 'arm64')]
+  [string]$Architecture,
   [ValidateNotNullOrEmpty()]
   [string]$DepCtrlVersion = "0.8.1"
 )
@@ -92,9 +95,9 @@ if ((Get-CachedDepCtrlVersion $DepCtrlDir) -ne $DepCtrlVersion) {
 # 	Remove-Item $avsArchive
 # }
 
-# VSFilter
+# VSFilter has no ARM64 build; libass remains the subtitle renderer there.
 $VSFilterDir = Join-Path $DepsDir "VSFilter"
-if (!(Test-Path $VSFilterDir)) {
+if ($Architecture -eq 'x64' -and !(Test-Path $VSFilterDir)) {
 	New-Item -ItemType Directory -Path $VSFilterDir | Out-Null
 	$vsFilterReleases = Invoke-WebRequest "https://api.github.com/repos/pinterf/xy-VSFilter/releases/latest" -Headers $GitHeaders -UseBasicParsing | ConvertFrom-Json
 	$vsFilterUrl = $vsFilterReleases.assets[0].browser_download_url
@@ -108,7 +111,8 @@ if (!(Test-Path $VSFilterDir)) {
 $RedistDir = Join-Path $DepsDir "VC_redist"
 if (!(Test-Path $RedistDir)) {
 	New-Item -ItemType Directory -Path $RedistDir | Out-Null
-	Invoke-WebRequest https://aka.ms/vs/17/release/VC_redist.x64.exe -OutFile (Join-Path $RedistDir "VC_redist.x64.exe") -UseBasicParsing
+	$redistUrl = "https://aka.ms/vc14/vc_redist.$Architecture.exe"
+	Invoke-WebRequest $redistUrl -OutFile (Join-Path $RedistDir "VC_redist.$Architecture.exe") -UseBasicParsing
 }
 
 # Dictionaries
@@ -139,5 +143,8 @@ if(!$?) { Exit $LASTEXITCODE }
 
 # Invoke InnoSetup
 $IssUrl = Join-Path $InstallerDir "aegisub_depctrl.iss"
-iscc $IssUrl
+$isccArgs = @()
+if ($Architecture -eq 'arm64') { $isccArgs += '/DARM64' }
+$isccArgs += $IssUrl
+iscc @isccArgs
 if(!$?) { Exit $LASTEXITCODE }