Host capture gain works on punktfunk/1, and boosting no longer hard-clips (#229)

Sign Windows releases with Azure Artifact Signing — a 3-day leaf makes timestamping mandatory

.gitea/workflows/audit.yml

@@ -9,11 +9,13 @@
 #                   login gate, session sealing, mgmt bearer token), sdk (@punktfunk/host),
 #                   plugin-kit (@punktfunk/plugin-kit).
 #   * pnpm audit  → clients/decky (the Steam Deck plugin).
-#   * docs-site   → scanned NON-blocking (continue-on-error): known transitive advisories ride in
-#                   via the CMS/UI chain (@unom/ui → payload → dompurify/monaco) and the nitropack
-#                   build chain (node-tar, brace-expansion); clearing them needs coordinated bumps
-#                   verified against the LIVE site (the docs don't build standalone) — tracked in
-#                   punktfunk-planning design/cra-readiness.md. Flip to blocking once clean.
+#   * docs-site   → scanned NON-blocking (continue-on-error). 2026-08-14: docs-site's own deps
+#                   are current (fumadocs/tanstack/react bumped; build + tsc + serve verified),
+#                   but every remaining advisory is pinned INSIDE @unom/ui 0.9.2's dependency
+#                   tree (@payloadcms/* → fast-uri/image-size/sharp, next 16.x, sass→immutable) —
+#                   nothing bumpable from this lockfile, and overrides would fork what the CMS
+#                   actually ships. The fix belongs in the @unom/ui package repo; flip this to
+#                   blocking after a ui release with a clean payload chain lands here.
 #   * cargo-about → license-allowlist gate over the host + driver workspaces (about.toml `accepted`);
 #                   fails if any crate carries a license outside the allowlist — the regression
 #                   guard about.toml always promised. (The Android Gradle tree has no lockfile, so

.gitea/workflows/windows-client.yml

@@ -257,6 +257,19 @@ jobs:
         if: github.event_name != 'pull_request'
         shell: pwsh
         env:
+          # Azure Artifact Signing (formerly Trusted Signing) — takes precedence over MSIX_CERT_*
+          # when all three are set. Not secret: an account/profile name and a regional endpoint,
+          # inert without the credentials below. The profile's verified subject is also the MSIX
+          # manifest Publisher; pack-msix.ps1 reads the signature back and fails on a mismatch.
+          AZURE_CODESIGNING_ENDPOINT: https://neu.codesigning.azure.net/
+          AZURE_CODESIGNING_ACCOUNT: unomsigning
+          AZURE_CODESIGNING_PROFILE: unom-io
+          # Service principal 'punktfunk-ci-signing', holding ONLY the Artifact Signing Certificate
+          # Profile Signer role, scoped to the unom-io profile — it can sign and nothing else.
+          AZURE_TENANT_ID: ${{ secrets.AZURE_TENANT_ID }}
+          AZURE_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
+          AZURE_CLIENT_SECRET: ${{ secrets.AZURE_CLIENT_SECRET }}
+          # Legacy self-signed path, kept as the fallback for builds without Azure access.
           MSIX_CERT_PFX_B64: ${{ secrets.MSIX_CERT_PFX_B64 }}
           MSIX_CERT_PASSWORD: ${{ secrets.MSIX_CERT_PASSWORD }}
         run: |

.gitea/workflows/windows-host.yml

@@ -20,12 +20,18 @@
 #   main push / dispatch -> <next-minor>.<run_number>  (canary; `canary/` alias; base one minor
 #                          ahead of the latest stable tag via scripts/ci/pf-version.ps1, run climbs).
 #
-# Signing reuses the client's MSIX_CERT_PFX_B64 / MSIX_CERT_PASSWORD secrets (CN=unom). Without them
-# an ephemeral self-signed cert is generated and its public .cer published next to the installer
-# (import once to LocalMachine\TrustedPublisher). That fallback is for canary/CI ONLY — on a v* tag
+# Signing goes through Azure Artifact Signing (account `unomsigning`, profile `unom-io`) — a publicly
+# trusted CA, so there is no .cer for users to import and no SmartScreen "unknown publisher" prompt.
+# It falls back to the old MSIX_CERT_PFX_B64 / MSIX_CERT_PASSWORD self-signed cert, and then to an
+# ephemeral one, for builds without Azure access. Those fallbacks are for canary/CI ONLY — on a v* tag
 # the pack script FAILS CLOSED rather than ship a release signed by a per-build throwaway cert.
 # See packaging/windows/pack-host-installer.ps1.
 #
+# The bundled DRIVERS are NOT signed by Azure — they keep their own DRIVER_CERT_* cert and are still
+# trusted by planting that cert in the machine Root store at install time. Independent by design:
+# Windows checks the installer's signature via SmartScreen/UAC and driver catalogs via PnP, and never
+# requires a common signer. See packaging/windows/README.md for why that root-plant is still there.
+#
 # GPU backends: the host builds with --features nvenc,amf-qsv,qsv = all three vendors in one installer.
 #  - NVENC (NVIDIA, direct SDK): nothing needed at build time — the entry points are resolved at
 #    RUNTIME from the driver's nvEncodeAPI64.dll (a link-time import would kill the binary on
@@ -415,12 +421,26 @@ jobs:
       - name: Pack + sign installer
         shell: pwsh
         env:
+          # Azure Artifact Signing (formerly Trusted Signing) — takes precedence over MSIX_CERT_*
+          # when all three of these are set. Not secret: an account/profile name and a regional
+          # endpoint, all inert without the credentials below, so they live here where a reviewer
+          # can see which profile a release was signed by.
+          AZURE_CODESIGNING_ENDPOINT: https://neu.codesigning.azure.net/
+          AZURE_CODESIGNING_ACCOUNT: unomsigning
+          AZURE_CODESIGNING_PROFILE: unom-io
+          # Service principal 'punktfunk-ci-signing', holding ONLY the Artifact Signing Certificate
+          # Profile Signer role, scoped to the unom-io profile — it can sign and nothing else.
+          AZURE_TENANT_ID: ${{ secrets.AZURE_TENANT_ID }}
+          AZURE_CLIENT_ID: ${{ secrets.AZURE_CLIENT_ID }}
+          AZURE_CLIENT_SECRET: ${{ secrets.AZURE_CLIENT_SECRET }}
+          # Legacy self-signed path, kept as the fallback for builds without Azure access.
           MSIX_CERT_PFX_B64: ${{ secrets.MSIX_CERT_PFX_B64 }}
           MSIX_CERT_PASSWORD: ${{ secrets.MSIX_CERT_PASSWORD }}
           # The DRIVER cert is separate from the host/MSIX one and reaches the two driver build
           # scripts through the environment (pack-host-installer.ps1 invokes them, they read
           # $env:DRIVER_CERT_PFX_B64 themselves). Without it they sign with a per-build throwaway,
           # which the installer then trusts as a machine root — see packaging/windows/README.md.
+          # NOT moved to Azure: driver catalogs are a separate track, see that README.
           DRIVER_CERT_PFX_B64: ${{ secrets.DRIVER_CERT_PFX_B64 }}
           DRIVER_CERT_PASSWORD: ${{ secrets.DRIVER_CERT_PASSWORD }}
         run: |

SECURITY.md

@@ -5,13 +5,17 @@ machine, so we take security reports seriously and appreciate responsible disclo
 
 ## Supported versions
 
-Punktfunk ships on two tracks — **stable** (a `vX.Y.Z` tag; the current line is **0.22.x**) and
+Punktfunk ships on two tracks — **stable** (a `vX.Y.Z` tag) and
 **canary** (built from `main`). Fixes ship as a new release on those tracks; in practice
 we don't backport to older minor versions, so the supported versions are the latest stable release
 and the current canary build. If you're on an older build, please check that the issue still
 reproduces on the latest stable before reporting it. See
 [Release Channels](https://docs.punktfunk.unom.io/docs/channels).
 
+Security fixes are **free of charge**, ship **without undue delay**, and are **separated from
+feature updates where feasible**: on the stable track they arrive as patch releases (`vX.Y.Z+1`)
+that carry the fix rather than waiting on the next feature release.
+
 ## Reporting a vulnerability
 
 **Please report security issues privately by email to security@punktfunk.com.**

clients/windows/packaging/AppxManifest.xml

@@ -3,8 +3,14 @@
   MSIX package manifest for the punktfunk Windows client (WinUI 3 via windows-reactor).
 
   This is a TEMPLATE: packaging/pack-msix.ps1 substitutes {VERSION} (4-part numeric, e.g.
-  0.2.137.0) and {PUBLISHER} (must EXACTLY equal the signing cert's subject DN — default
-  `CN=unom` for the self-signed CI cert; a real code-signing cert just passes its own subject).
+  0.2.137.0) and {PUBLISHER} (must EXACTLY equal the signing cert's subject DN — the default is
+  the verified subject of the Azure `unom-io` certificate profile; the self-signed fallback mints
+  a throwaway cert with that same subject so canary and release share a package identity).
+
+  Package identity is Name + Publisher, so changing {PUBLISHER} makes this a DIFFERENT package:
+  installs of the older publisher cannot be upgraded in place and must be uninstalled first. That
+  is a user-visible migration, not a packaging detail — mention it in the release notes. pack-msix.ps1
+  reads the signature back off the packed .msix and fails the build if the two ever drift.
 
   Why this packages cleanly even though the app was built "unpackaged": windows-reactor calls
   MddBootstrapInitialize2 with OnPackageIdentity_NOOP (crates/libs/reactor/src/app.rs), so under

clients/windows/packaging/README.md

@@ -56,34 +56,45 @@ MSIX requires a strictly 4-part numeric version. The workflow computes:
 
 ## Signing & install
 
-CI signs every build with a **stable self-signed code-signing cert** (`CN=unom`, SHA-1
-`CD1EFDEEEC9743AFC38F56C5AF30C5A3009BE941`, valid to 2036). Its public half is checked in as
-[`punktfunk-codesign.cer`](punktfunk-codesign.cer); the private `.pfx` + password live in the
-`MSIX_CERT_PFX_B64` / `MSIX_CERT_PASSWORD` Actions secrets. Because it's the *same* cert every build,
-trusting it is **one-time, per machine** — once imported, every future build and in-place upgrade is
-trusted with no further prompt:
+CI signs every build with **Azure Artifact Signing** (formerly Trusted Signing) — account
+`unomsigning`, certificate profile `unom-io`, endpoint `https://neu.codesigning.azure.net/`. That
+chain is publicly trusted, so **there is nothing to import**:
 
 ```powershell
-# once per machine (elevated): trust the publisher
-Import-Certificate -FilePath .\punktfunk-codesign.cer -CertStoreLocation Cert:\LocalMachine\TrustedPeople
-# then install the package for your CPU (and re-run for each upgrade — no re-trust needed)
+# install the package for your CPU (and re-run for each upgrade)
 Add-AppxPackage -Path .\punktfunk-client-windows_<ver>_x64.msix     # Intel/AMD
 Add-AppxPackage -Path .\punktfunk-client-windows_<ver>_arm64.msix   # ARM64 (Snapdragon, etc.)
 ```
 
-The matching `.cer` is also published next to each `.msix` in the registry, so it's always at hand.
-
 The MSIX declares a dependency on the Windows App SDK 2.x runtime; install
 [the App SDK runtime](https://aka.ms/windowsappsdk) if `Add-AppxPackage` reports a missing
 `Microsoft.WindowsAppRuntime.2` framework.
 
-`pack-msix.ps1` signing precedence: it uses the **`MSIX_CERT_PFX_B64` / `MSIX_CERT_PASSWORD`** secrets
-when present (the stable cert above), else generates an *ephemeral* self-signed cert (forks / local
-builds without the secrets). Either way it exports the signing cert's public `.cer` for the import.
-**To move to a publicly-trusted (no-import) cert** — Azure Artifact Signing or a public OV cert —
-replace the two secrets with the new `.pfx`; the cert's subject DN must equal the manifest
-`Publisher`, so pass a matching `-Publisher` (it's stamped into the package `Identity`, and changing
-it changes the package identity → a one-time reinstall).
+### How signing resolves
+
+`pack-msix.ps1` picks a backend in this order:
+
+1. **Azure Artifact Signing** when `AZURE_CODESIGNING_ENDPOINT` / `_ACCOUNT` / `_PROFILE` are all
+   set (the workflow sets them; they aren't secret). Credentials come from `AZURE_TENANT_ID` /
+   `AZURE_CLIENT_ID` / `AZURE_CLIENT_SECRET` — the `punktfunk-ci-signing` service principal, which
+   holds only the *Artifact Signing Certificate Profile Signer* role scoped to the `unom-io` profile.
+   Keys are HSM-backed and never leave Azure, so there is no `.pfx` and no `.cer` is emitted.
+2. **`MSIX_CERT_PFX_B64` / `MSIX_CERT_PASSWORD`** — the older stable self-signed cert (`CN=unom`,
+   public half checked in as [`punktfunk-codesign.cer`](punktfunk-codesign.cer)), kept as a fallback.
+3. An **ephemeral** self-signed cert (forks / local builds with no secrets at all).
+
+Modes 2 and 3 still export a `.cer` to import into `Cert:\LocalMachine\TrustedPeople` first. On a
+`v*` tag, a build with no real signing backend **fails closed** rather than shipping a throwaway.
+
+Two things about Azure mode that are easy to get wrong:
+
+- **Timestamping is mandatory, not best-effort.** Azure mints a leaf cert per request that expires in
+  about three days. An untimestamped signature therefore stops verifying within days of release, so
+  the script refuses to retry without one (modes 2 and 3 keep the old best-effort retry).
+- **The manifest `Publisher` must equal the signer's subject exactly**, because MSIX package identity
+  is Name + Publisher. The default `-Publisher` is the `unom-io` profile's verified subject; after
+  signing, the script reads the signature back off the `.msix` and fails the build on any drift.
+  Changing it makes a *different* package — existing installs must be uninstalled, not upgraded.
 
 ## Building locally
 

clients/windows/packaging/pack-msix.ps1

@@ -13,15 +13,22 @@
   packaging/windows/pack-host-installer.ps1 still ships them for its amf-qsv encode path.
 
   Signing cert precedence:
+    0. Azure Artifact Signing (formerly Trusted Signing) when AZURE_CODESIGNING_ENDPOINT/_ACCOUNT/
+       _PROFILE are all set. HSM-backed, so there is no .pfx and nothing to export: the chain is
+       publicly trusted, so no .cer is produced and MSIX_CER_PATH stays unset.
     1. -PfxBase64 / -PfxPassword  (a real or shared code-signing cert, e.g. from CI secrets) — the
        cert's subject DN MUST match -Publisher (which is stamped into the manifest Identity).
     2. otherwise an EPHEMERAL self-signed code-signing cert with subject = -Publisher is generated
        in-process. The package installs only where that cert is trusted, so the matching public
        .cer is exported next to the .msix for the user to import (Trusted People) before install.
-       Swap in a real cert later with zero manifest changes — just pass -PfxBase64/-Publisher.
        This fallback is for canary/CI/dev ONLY: on a v* tag build a missing cert is a hard failure
        (-RequireSignedCert), never a silent downgrade to a throwaway cert.
 
+  WHICHEVER mode runs, the signed .msix is read back and its signer subject compared to -Publisher;
+  a mismatch fails the build. MSIX package identity is Name + Publisher, so a publisher that does
+  not match the signer is not a cosmetic problem — Add-AppxPackage rejects the package outright,
+  and it would only be discovered by a user trying to install the release.
+
   Run on the Windows runner (or the dev VM) with the MSVC/Windows SDK present.
 
 .EXAMPLE
@@ -36,9 +43,21 @@ param(
     [Parameter(Mandatory = $true)][string]$TargetDir,                   # cargo --release output dir (has the exe)
     [ValidateSet('x64', 'arm64')][string]$Arch = 'x64',                 # package ProcessorArchitecture + artifact suffix
     [string]$OutDir = (Join-Path $TargetDir 'msix'),
-    [string]$Publisher = 'CN=unom',                                     # MUST equal the signing cert subject DN
+    # MUST equal the signing cert subject DN — this is the verified subject the Azure 'unom-io'
+    # certificate profile issues. The 'ü' is written as an escape, not a literal: this file is UTF-8
+    # with no BOM, and read by anything other than pwsh 7 a literal would silently mojibake into a
+    # publisher that no longer matches the signer, which surfaces only as an Add-AppxPackage refusal
+    # on a user's machine. Verified against the real signer after signing below.
+    [string]$Publisher = "CN=unom - Enrico B$([char]0xFC)hler, O=unom - Enrico B$([char]0xFC)hler, L=Rottweil, S=Baden-W$([char]0xFC)rttemberg, C=DE",
     [string]$PfxBase64 = $env:MSIX_CERT_PFX_B64,                        # optional: base64 of a code-signing .pfx
     [string]$PfxPassword = $env:MSIX_CERT_PASSWORD,
+    # Azure Artifact Signing. All three select it, ahead of any .pfx. Credentials arrive through the
+    # environment via DefaultAzureCredential (AZURE_TENANT_ID / AZURE_CLIENT_ID / AZURE_CLIENT_SECRET)
+    # rather than as arguments, so they cannot leak into a process listing or a transcript.
+    [string]$AzureEndpoint = $env:AZURE_CODESIGNING_ENDPOINT,           # e.g. https://neu.codesigning.azure.net/
+    [string]$AzureAccount = $env:AZURE_CODESIGNING_ACCOUNT,             # signing account name
+    [string]$AzureProfile = $env:AZURE_CODESIGNING_PROFILE,             # certificate profile name
+    [string]$AzureDlib = $env:AZURE_CODESIGNING_DLIB,                   # path to Azure.CodeSigning.Dlib.dll
     # 'auto' (default) = required iff this is a v* tag build; 'true'/'false' to force. See below.
     [ValidateSet('auto', 'true', 'false')][string]$RequireSignedCert = 'auto'
 )
@@ -64,6 +83,28 @@ function Find-SdkTool([string]$name) {
     if (-not $hit) { throw "$name not found under $root — install the Windows 10/11 SDK." }
     $hit.FullName
 }
+# Azure.CodeSigning.Dlib.dll ships in the Microsoft.Trusted.Signing.Client NuGet package, which has
+# no installer and no fixed location — hence an explicit override first, then the paths the runner
+# setup uses (packaging/windows/README.md). Newest wins, so a package update needs no edit here.
+function Find-AzureDlib([string]$Explicit) {
+    if ($Explicit) {
+        if (-not (Test-Path $Explicit)) { throw "AZURE_CODESIGNING_DLIB points at a missing file: $Explicit" }
+        return (Resolve-Path $Explicit).Path
+    }
+    $roots = @(
+        (Join-Path $env:USERPROFILE '.nuget\packages\microsoft.trusted.signing.client'),
+        'C:\trusted-signing\microsoft.trusted.signing.client'
+    ) | Where-Object { $_ -and (Test-Path $_) }
+    $hit = $roots | ForEach-Object { Get-ChildItem -Path $_ -Recurse -Filter 'Azure.CodeSigning.Dlib.dll' -ErrorAction SilentlyContinue } |
+        Where-Object { $_.FullName -match '\\bin\\x64\\' } |
+        Sort-Object LastWriteTime | Select-Object -Last 1
+    if (-not $hit) {
+        throw ("Azure.CodeSigning.Dlib.dll not found. Install the signing client on this box, e.g. " +
+               "``nuget install Microsoft.Trusted.Signing.Client -OutputDirectory " +
+               "`$env:USERPROFILE\.nuget\packages``, or set AZURE_CODESIGNING_DLIB to its full path.")
+    }
+    $hit.FullName
+}
 $makeappx = Find-SdkTool 'makeappx.exe'
 $signtool = Find-SdkTool 'signtool.exe'
 Write-Host "makeappx: $makeappx"
@@ -159,13 +200,34 @@ $requireCert = if ($RequireSignedCert -eq 'auto') { $env:GITHUB_REF -like 'refs/
                else { [Convert]::ToBoolean($RequireSignedCert) }
 $pfxPath = Join-Path $OutDir 'signing.pfx'
 $cerPath = Join-Path $OutDir "punktfunk-client-windows_${Version}_${Arch}.cer"
-if ($PfxBase64) {
+$azureMetadata = Join-Path $OutDir 'azure-codesigning.json'
+$signMode = 'selfsigned'
+if ($AzureEndpoint -and $AzureAccount -and $AzureProfile) {
+    $signMode = 'azure'
+    $AzureDlib = Find-AzureDlib $AzureDlib
+    # signtool takes the account/profile from this file (/dmdf), not the command line.
+    @{
+        Endpoint               = $AzureEndpoint
+        CodeSigningAccountName = $AzureAccount
+        CertificateProfileName = $AzureProfile
+    } | ConvertTo-Json | Set-Content -Path $azureMetadata -Encoding utf8
+    Write-Host "signing via Azure Artifact Signing: $AzureAccount/$AzureProfile at $AzureEndpoint"
+    Write-Host "  dlib: $AzureDlib"
+    foreach ($v in 'AZURE_TENANT_ID', 'AZURE_CLIENT_ID', 'AZURE_CLIENT_SECRET') {
+        if (-not [Environment]::GetEnvironmentVariable($v)) {
+            throw ("Azure signing selected but $v is not set. The dlib authenticates with " +
+                   "DefaultAzureCredential; without the service-principal trio it falls through to an " +
+                   "interactive login that cannot complete on a runner and hangs the build.")
+        }
+    }
+} elseif ($PfxBase64) {
+    $signMode = 'pfx'
     Write-Host "signing with supplied code-signing cert (MSIX_CERT_PFX_B64)"
     [IO.File]::WriteAllBytes($pfxPath, [Convert]::FromBase64String($PfxBase64))
 } elseif ($requireCert) {
-    throw ("release build ($env:GITHUB_REF) with no MSIX_CERT_PFX_B64 — refusing to fall back to an " +
-           "ephemeral self-signed cert. Restore the MSIX_CERT_PFX_B64 / MSIX_CERT_PASSWORD repo " +
-           "secrets, or pass -RequireSignedCert false if this really is a test build.")
+    throw ("release build ($env:GITHUB_REF) with neither AZURE_CODESIGNING_* nor MSIX_CERT_PFX_B64 — " +
+           "refusing to fall back to an ephemeral self-signed cert. Restore the signing secrets " +
+           "(packaging/windows/README.md), or pass -RequireSignedCert false if this really is a test build.")
 } else {
     Write-Host "no MSIX_CERT_PFX_B64 -> generating an ephemeral self-signed cert (subject $Publisher)"
     if (-not $PfxPassword) { $PfxPassword = 'punktfunk' }
@@ -178,35 +240,80 @@ if ($PfxBase64) {
     Remove-Item "Cert:\CurrentUser\My\$($tmp.Thumbprint)" -Force
 }
 
-# Always export the public .cer from the pfx. For a self-signed / private-trust cert it's the file
-# users import once (Trusted People) — a STABLE cert (same pfx every build via the secret) means that
-# import is a one-time, per-machine step that keeps working across upgrades. For a public-CA cert
-# it's just an unused extra (harmless). The manifest Publisher must equal the cert's subject DN.
-$pwsec = if ($PfxPassword) { ConvertTo-SecureString -String $PfxPassword -Force -AsPlainText } else { $null }
-$pubCert = if ($pwsec) { Get-PfxCertificate -FilePath $pfxPath -Password $pwsec } else { Get-PfxCertificate -FilePath $pfxPath }
-Export-Certificate -Cert $pubCert -FilePath $cerPath | Out-Null
-Write-Host "signing cert subject=$($pubCert.Subject) thumbprint=$($pubCert.Thumbprint)"
-if ($pubCert.Subject -ne $Publisher) {
-    Write-Warning "cert subject '$($pubCert.Subject)' != manifest Publisher '$Publisher' — Add-AppxPackage will reject the mismatch. Pass -Publisher '$($pubCert.Subject)'."
+# Export the public .cer from the pfx. For a self-signed / private-trust cert it's the file users
+# import once (Trusted People) — a STABLE cert (same pfx every build via the secret) means that
+# import is a one-time, per-machine step that keeps working across upgrades. Azure signing is
+# HSM-backed: there is no pfx to read and its chain is publicly trusted, so no .cer is produced.
+if ($signMode -ne 'azure') {
+    $pwsec = if ($PfxPassword) { ConvertTo-SecureString -String $PfxPassword -Force -AsPlainText } else { $null }
+    $pubCert = if ($pwsec) { Get-PfxCertificate -FilePath $pfxPath -Password $pwsec } else { Get-PfxCertificate -FilePath $pfxPath }
+    Export-Certificate -Cert $pubCert -FilePath $cerPath | Out-Null
+    Write-Host "signing cert subject=$($pubCert.Subject) thumbprint=$($pubCert.Thumbprint)"
 }
 
-# --- sign (timestamp best-effort) ---
-$signArgs = @('sign', '/fd', 'SHA256', '/f', $pfxPath)
-if ($PfxPassword) { $signArgs += @('/p', $PfxPassword) }
-& $signtool ($signArgs + @('/tr', 'http://timestamp.digicert.com', '/td', 'SHA256', $msix))
+# --- sign ---
+# The timestamp is best-effort for a .pfx whose cert outlives the release, but MANDATORY under Azure
+# signing: those leaf certs are minted per request and expire in ~3 days, so an untimestamped
+# signature stops verifying within days of shipping. Retrying without one there would produce a
+# package that installs on the runner and fails for every user that weekend — so the fallback is
+# gated on the mode rather than applied blindly.
+if ($signMode -eq 'azure') {
+    $signArgs = @('sign', '/fd', 'SHA256', '/dlib', $AzureDlib, '/dmdf', $azureMetadata)
+    $ts = 'http://timestamp.acs.microsoft.com'
+} else {
+    $signArgs = @('sign', '/fd', 'SHA256', '/f', $pfxPath)
+    if ($PfxPassword) { $signArgs += @('/p', $PfxPassword) }
+    $ts = 'http://timestamp.digicert.com'
+}
+& $signtool ($signArgs + @('/tr', $ts, '/td', 'SHA256', $msix))
 if ($LASTEXITCODE -ne 0) {
+    if ($signMode -eq 'azure') {
+        throw ("timestamped sign failed ($LASTEXITCODE) — NOT retrying without a timestamp. An Azure " +
+               "signing cert is valid for ~3 days; an untimestamped signature would go untrusted " +
+               "within days of release.")
+    }
     Write-Warning "timestamped sign failed — retrying without a timestamp"
     & $signtool ($signArgs + @($msix))
     if ($LASTEXITCODE -ne 0) { throw "signtool sign failed ($LASTEXITCODE)" }
 }
 Remove-Item $pfxPath -Force -ErrorAction SilentlyContinue
+Remove-Item $azureMetadata -Force -ErrorAction SilentlyContinue
+
+# Read the signature back off the packed .msix and hold it against the manifest Publisher. MSIX
+# package identity is Name + Publisher, so a publisher that doesn't match the signer isn't cosmetic:
+# Add-AppxPackage refuses the package outright. Checking the ACTUAL signer (rather than a pfx we
+# happen to hold) is the only form of this check that works in every signing mode, and failing the
+# build here is the difference between a red pipeline and a release nobody can install.
+# Deliberately asymmetric: a subject we CAN read and that DISAGREES is a hard failure, but a subject
+# we cannot read at all is only a warning. Get-AuthenticodeSignature's support for the .msix/.appx
+# subject interface varies by Windows version, and signtool has already reported success by this
+# point — turning "the check could not run" into a build break would trade a real defect we catch for
+# an imaginary one we invent.
+$signerSubject = $null
+try { $signerSubject = (Get-AuthenticodeSignature $msix).SignerCertificate.Subject } catch { }
+if (-not $signerSubject) {
+    Write-Warning ("could not read a signer subject back from $msix, so Publisher/signer agreement is " +
+                   "UNVERIFIED on this box. If the package is rejected at Add-AppxPackage time, compare " +
+                   "`signtool verify /pa /v` against the manifest Publisher '$Publisher' by hand.")
+} elseif ($signerSubject -ne $Publisher) {
+    throw ("signer subject does not match the manifest Publisher, so this package cannot install:`n" +
+           "  signer    : '$signerSubject'`n" +
+           "  Publisher : '$Publisher'`n" +
+           "Pass -Publisher '$signerSubject' (or fix the certificate profile) and repack.")
+} else {
+    Write-Host "verified signer subject matches manifest Publisher: $signerSubject"
+}
 
 Write-Host ""
 Write-Host "==> MSIX: $msix"
-Write-Host "==> trust the cert once per machine (then it stays trusted across all future builds):"
-Write-Host "    Import-Certificate -FilePath '$cerPath' -CertStoreLocation Cert:\LocalMachine\TrustedPeople"
+if ($signMode -eq 'azure') {
+    Write-Host "==> signed by a publicly trusted CA — nothing for users to import."
+} else {
+    Write-Host "==> trust the cert once per machine (then it stays trusted across all future builds):"
+    Write-Host "    Import-Certificate -FilePath '$cerPath' -CertStoreLocation Cert:\LocalMachine\TrustedPeople"
+}
 # emit paths for the workflow to publish (only under CI, where GITHUB_ENV is set)
 if ($env:GITHUB_ENV) {
     "MSIX_PATH=$msix" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8
-    "MSIX_CER_PATH=$cerPath" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8
+    if ($signMode -ne 'azure') { "MSIX_CER_PATH=$cerPath" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8 }
 }

compliance/sbom/manual-components.cdx.json

@@ -62,10 +62,18 @@
     {
       "type": "application",
       "name": "punktfunk-gamescope",
-      "version": "upstream gamescope pinned by packaging/nix/gamescope.nix (nixpkgs) or built by packaging/gamescope/build-punktfunk-gamescope.sh, plus 3 local patches from packaging/gamescope/patches/",
+      "version": "upstream gamescope pinned by packaging/nix/gamescope.nix (nixpkgs) or built by packaging/gamescope/build-punktfunk-gamescope.sh, plus the local patch series from packaging/gamescope/patches/",
       "description": "Patched gamescope compositor distributed via sysext/Arch/nix channels alongside the host",
       "licenses": [{ "license": { "id": "BSD-2-Clause" } }],
       "externalReferences": [{ "type": "vcs", "url": "https://github.com/ValveSoftware/gamescope" }]
+    },
+    {
+      "type": "application",
+      "name": "Bun",
+      "version": "1.3.14 (pinned in .gitea/workflows/windows-host.yml)",
+      "description": "Portable JavaScript runtime bundled in the Windows host installer to run the web console (.output) and the plugin/script runner. Embeds JavaScriptCore (LGPL-2.1).",
+      "licenses": [{ "license": { "id": "MIT" } }],
+      "externalReferences": [{ "type": "vcs", "url": "https://github.com/oven-sh/bun" }]
     }
   ]
 }

compliance/vendored-components.md

@@ -0,0 +1,51 @@
+# Vendored & bundled components — CVE watch and update cadence
+
+Due-diligence record for every third-party component that ships with Punktfunk but is
+**not** tracked by a package manager's advisory feed (CRA Art. 13(5); Annex I Part II §1).
+Everything resolved through Cargo/bun/pnpm lockfiles is already scanned weekly by
+`.gitea/workflows/audit.yml` (cargo-audit against RustSec, bun/pnpm audit) — this file
+covers what those scanners cannot see: vendored source trees, git-rev pins, and binaries
+staged into installers. The component inventory itself lives in
+`compliance/sbom/manual-components.cdx.json` and is merged into every release SBOM;
+keep the two files in sync when a component is added, removed, or re-pinned.
+
+Owner for all of it: Enrico (sole maintainer). Standing cadence: **walk this table once
+per quarter and before every stable release**; act immediately on any advisory from the
+watch feeds below.
+
+| Component | Where / pin | How to update | Watch |
+|---|---|---|---|
+| **pyrowave** (+ Granite, volk, Vulkan-Headers subtree) | `crates/pyrowave-sys/vendor/pyrowave`, pin = `PYROWAVE_COMMIT` in `scripts/vendor-pyrowave.sh`; exact commits recorded in `vendor/pyrowave/PUNKTFUNK-VENDOR.txt` | Bump the commit in the script, re-run it (network required; never from CI), re-apply `crates/pyrowave-sys/patches/`. ⚠️ **Bitstream changes are protocol-affecting** — the wire bit means "PyroWave as of this pin"; a bitstream-changing bump must bump the protocol version and re-diff the Apple Metal hand-port (see the script header). | GitHub releases/commits of Themaister/pyrowave + Themaister/Granite (niche projects, no CVE feed — repo watch is the feed) |
+| **libvpl** 2.17.0 | `crates/libvpl-sys/vendor/libvpl` (dispatcher statically linked; needs cmake + libclang) | Manual re-vendor from intel/libvpl at the new tag; rebuild `libvpl-sys` | Intel Security Center (INTEL-SA advisories for oneVPL/media) + intel/libvpl releases |
+| **windows-rs** git pin | `rev = acb5a1a7…` on microsoft/windows-rs (workspace `[patch]`/git deps: `windows`, `windows-reactor`, …) | Move the rev / return to crates.io once the needed fixes are released. Note: cargo-audit matches these by name+version from Cargo.lock, but a pre-release rev may not map cleanly onto RustSec advisories — treat the pin itself as the thing to retire. | RustSec (already weekly) + microsoft/windows-rs releases |
+| **usbfs-iso / uac-host** git pin | `rev = f3de1fd…` on unom-io/usbfs-iso | First-party fork — we are upstream; fix in the fork, move the rev | Own repo (issues land in our tracker) |
+| **FFmpeg** (host encode only) | Linux: system `libav*` (distro-updated, not ours to patch — but Arch soname majors can break us, see ffmpeg9 note). Windows: AMF/QSV shared DLLs staged from `FFMPEG_DIR` by `pack-host-installer.ps1`; LGPL notice bundled | Windows: rebuild/refresh the staged DLL set, ship in the next installer. Linux: nothing to ship; verify against new distro majors | ffmpeg-security announcements (ffmpeg.org security page) — a libav* CVE in decode/parse paths we use ⇒ refresh the Windows DLLs without undue delay |
+| **SDL3** | Desktop clients, dynamically linked; system-provided or bundled per platform package | Bump the bundled copy in the affected package; system copies are distro-updated | libsdl-org/SDL GitHub security advisories + releases |
+| **gamescope** + patch series | Pin in `packaging/nix/gamescope.nix` / built by `packaging/gamescope/build-punktfunk-gamescope.sh`; local patches in `packaging/gamescope/patches/` | Bump the pin, re-rebase the patch series, rebuild sysext/Arch/nix + .deb channels. ⚠️ the gamescope CI legs are best-effort: a broken patch shows up as a *missing package*, not a red build | ValveSoftware/gamescope releases + security advisories |
+| **Bun runtime** 1.3.14 | Pinned in `.gitea/workflows/windows-host.yml` (`bun-v1.3.14`); bundled portable in the Windows host installer to run the web console + plugin runner. Embeds JavaScriptCore | Bump the version string in the workflow; next installer build picks it up | oven-sh/bun releases (security notes ride in release notes) |
+
+Not on this list on purpose:
+
+- **VB-CABLE** — no longer bundled (audio-substrate program, 2026-08; the host mints its
+  own virtual audio devices). If it ever returns, it returns to this table first.
+- **openh264 / rav1d CPU decode floor** — crates.io dependencies with vendored C/asm
+  inside the `-sys` crates; cargo-audit tracks the crate advisories, and the upstream
+  (Cisco openh264, memorysafety/rav1d) security feeds surface through RustSec. No
+  separate manual watch needed unless we pin them to git.
+
+## Security-update availability (CRA: ≥10 years)
+
+Where users fetch fixes, and why old artifacts don't vanish (verified 2026-08-14):
+
+- **Gitea releases + package registries** (git.unom.io): no cleanup rules configured,
+  and Gitea does not expire releases or packages on its own — the full release history
+  (v0.17.x through current) is still served with assets. Blobs live in the `unom-git`
+  S3 bucket with an R2 mirror, and the box is restic-backed every 6 h. Old release
+  assets (and their `.sha256` sidecars) therefore stay downloadable.
+- **Bazzite sysext feeds**: stable channels publish with `KEEP=0` (keep everything);
+  only canary channels prune (`KEEP=6`) — see `rpm.yml` + `publish-sysext-feed.sh`.
+- **Flatpak repo** (flatpak.unom.io): published by rsync *without* `--delete`; old
+  OSTree commits accumulate, both channels stay in the signed summary.
+- **Policy**: never add cleanup that deletes *security* releases; if storage pressure
+  ever forces pruning, prune canary builds, never tagged stable releases. SBOMs are
+  release assets, so the ≥10-year SBOM retention rides on the same guarantee.

crates/pf-vdisplay/protocols/dpms.xml

@@ -0,0 +1,87 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<protocol name="dpms">
+  <copyright><![CDATA[
+    SPDX-FileCopyrightText: 2015 Martin Gräßlin
+
+    SPDX-License-Identifier: LGPL-2.1-or-later
+  ]]></copyright>
+  <interface name="org_kde_kwin_dpms_manager" version="1">
+      <description summary="Output dpms manager">
+          The Dpms manager allows to get a org_kde_kwin_dpms for a given wl_output.
+          The org_kde_kwin_dpms provides the currently used VESA Display Power Management
+          Signaling state (see https://en.wikipedia.org/wiki/VESA_Display_Power_Management_Signaling ).
+          In addition it allows to request a state change. A compositor is not obliged to honor it
+          and will normally automatically switch back to on state.
+
+          Warning! The protocol described in this file is a desktop environment
+          implementation detail. Regular clients must not use this protocol.
+          Backward incompatible changes may be added without bumping the major
+          version of the extension.
+      </description>
+      <request name="get">
+          <description summary="Get org_kde_kwin_dpms for wl_output">
+              Factory request to get the org_kde_kwin_dpms for a given wl_output.
+          </description>
+          <arg name="id" type="new_id" interface="org_kde_kwin_dpms"/>
+          <arg name="output" type="object" interface="wl_output"/>
+      </request>
+  </interface>
+  <interface name="org_kde_kwin_dpms" version="1">
+      <description summary="Dpms for a wl_output">
+          This interface provides information about the VESA DPMS state for a wl_output.
+          It gets created through the request get on the org_kde_kwin_dpms_manager interface.
+
+          On creating the resource the server will push whether DPSM is supported for the output,
+          the currently used DPMS state and notifies the client through the done event once all
+          states are pushed. Whenever a state changes the set of changes is committed with the
+          done event.
+      </description>
+      <event name="supported">
+          <description summary="Event indicating whether DPMS is supported on the wl_output">
+              This event gets pushed on binding the resource and indicates whether the wl_output
+              supports DPMS. There are operation modes of a Wayland server where DPMS might not
+              make sense (e.g. nested compositors).
+          </description>
+          <arg name="supported" type="uint" summary="Boolean value whether DPMS is supported (1) for the wl_output or not (0)"/>
+      </event>
+      <enum name="mode">
+            <entry name="On" value="0"/>
+            <entry name="Standby" value="1"/>
+            <entry name="Suspend" value="2"/>
+            <entry name="Off" value="3"/>
+      </enum>
+      <event name="mode">
+          <description summary="Event indicating used DPMS mode">
+              This mode gets pushed on binding the resource and provides the currently used
+              DPMS mode. It also gets pushed if DPMS is not supported for the wl_output, in that
+              case the value will be On.
+
+              The event is also pushed whenever the state changes.
+          </description>
+          <arg name="mode" type="uint" summary="The new currently used mode"/>
+      </event>
+      <event name="done">
+          <description summary="All changes are pushed">
+              This event gets pushed on binding the resource once all other states are pushed.
+
+              In addition it gets pushed whenever a state changes to tell the client that all
+              state changes have been pushed.
+          </description>
+      </event>
+      <request name="set">
+          <description summary="Request DPMS state change for the wl_output">
+              Requests that the compositor puts the wl_output into the passed mode. The compositor
+              is not obliged to change the state. In addition the compositor might leave the mode
+              whenever it seems suitable. E.g. the compositor might return to On state on user input.
+
+              The client should not assume that the mode changed after requesting a new mode.
+              Instead the client should listen for the mode event.
+          </description>
+          <arg name="mode" type="uint" summary="Requested mode"/>
+      </request>
+      <request name="release" type="destructor">
+        <description summary="release the dpms object"/>
+      </request>
+  </interface>
+</protocol>
+

crates/pf-vdisplay/src/lib.rs

@@ -848,6 +848,15 @@ mod kwin;
 #[path = "vdisplay/linux/kwin_output_mgmt.rs"]
 mod kwin_output_mgmt;
 
+// DPMS control of the box's live KDE desktop (org_kde_kwin_dpms) — how a bare-spawn gamescope
+// session honors `Topology::Exclusive`: the spawn is its own headless compositor, so the desktop's
+// physical outputs can't be *disabled* (KWin refuses zero enabled outputs and no output there is
+// ours) — they are put to DPMS-off for the stream instead, refcounted across concurrent spawns.
+// Consumed by `gamescope` (best-effort, with kscreen fallback).
+#[cfg(target_os = "linux")]
+#[path = "vdisplay/linux/kwin_dpms.rs"]
+mod kwin_dpms;
+
 #[cfg(target_os = "windows")]
 #[path = "vdisplay/windows/manager.rs"]
 pub mod manager;

crates/pf-vdisplay/src/vdisplay/linux/gamescope.rs

@@ -69,6 +69,11 @@ pub struct GamescopeDisplay {
     /// the decision and this session's `create`. `None` = nothing resolved it (a caller that never
     /// ran `apply_input_env`); `create` then falls through to the bare spawn, the safe default.
     route: Option<crate::GamescopeRoute>,
+    /// The topology-restore action the bare-spawn `create` prepared under `Topology::Exclusive` —
+    /// the release of this display's [`crate::kwin_dpms`] darken hold — pending pickup by the
+    /// registry via [`VirtualDisplay::take_topology_restore`], so it runs at the display's
+    /// teardown (§6.1) and never before.
+    pending_restore: Option<Box<dyn FnOnce() + Send>>,
 }
 
 /// A running host-managed session (its transient systemd --user unit) + the mode it was launched at.
@@ -441,6 +446,14 @@ impl VirtualDisplay for GamescopeDisplay {
         self.route = route;
     }
 
+    fn take_topology_restore(&mut self) -> Option<Box<dyn FnOnce() + Send>> {
+        // The DPMS darken-hold release the bare-spawn `create` registered (Exclusive topology
+        // only). The registry stores it on this display's entry and runs it at teardown — which,
+        // for gamescope, is the display's OWN teardown: every spawn is its own group, and the
+        // cross-session ordering lives in `kwin_dpms`'s refcount, not in the group float.
+        self.pending_restore.take()
+    }
+
     fn poolable_now(&self) -> bool {
         // Only a bare SPAWN is registry-poolable (its `create` reports `Owned`); Managed and
         // Attach report `SessionManaged`/`External`, so the registry must not reuse a kept spawn
@@ -576,6 +589,23 @@ impl VirtualDisplay for GamescopeDisplay {
             hz = mode.refresh_hz,
             "gamescope virtual output ready"
         );
+        // `Topology::Exclusive`, bare-spawn edition: this spawn is its OWN headless compositor —
+        // nothing above touched the box's live desktop (KWin), which would otherwise keep driving
+        // the physical panel with the idle desktop for the whole stream. The KWin route disables
+        // the physicals outright, but that door is closed here (KWin refuses zero enabled outputs,
+        // and no output on that desktop is ours to leave enabled) — so the desktop's panels go to
+        // DPMS-off instead, best-effort and self-gating (a box with no KDE desktop declines
+        // quietly inside `kwin_dpms`). Placed AFTER the spawn succeeded, so a failed create never
+        // blanks the user's screen. The hold is refcounted in `kwin_dpms` rather than floated
+        // through the registry's group restore, because every gamescope spawn is its own group
+        // (`registry::group_key`) — the float alone would re-light the panel when the FIRST of two
+        // concurrent spawns ends, under the second's still-live stream. Skipped for Managed (its
+        // takeover already stopped the desktop) and Attach (it mirrors a gamescope that may itself
+        // be driving the physical panel) — both returned earlier in this function.
+        if crate::effective_topology() == crate::policy::Topology::Exclusive {
+            crate::kwin_dpms::acquire_stream_darken();
+            self.pending_restore = Some(Box::new(crate::kwin_dpms::release_stream_darken));
+        }
         // Bare SPAWN: we own the nested gamescope process → registry-poolable (keep-alive-able).
         Ok(VirtualOutput::owned(
             node_id,

crates/pf-vdisplay/src/vdisplay/linux/kwin.rs

@@ -704,7 +704,7 @@ fn kscreen_ok(args: &[String]) -> bool {
 /// before exiting, so a slow-but-working KWin gives us a kill on a request that already landed;
 /// any caller that treats `None` as "it failed" is asserting something it does not know, and for
 /// the restore path that assertion costs a monitor its refresh rate.
-fn kscreen_verdict(args: &[String]) -> Option<bool> {
+pub(crate) fn kscreen_verdict(args: &[String]) -> Option<bool> {
     match crate::proc::status_within(
         std::process::Command::new("kscreen-doctor").args(args),
         KSCREEN_BUDGET,

crates/pf-vdisplay/src/vdisplay/linux/kwin_dpms.rs

@@ -0,0 +1,675 @@
+//! DPMS control of the box's live KDE desktop (`org_kde_kwin_dpms`) — how a bare-spawn gamescope
+//! session honors [`Topology::Exclusive`](crate::policy::Topology::Exclusive).
+//!
+//! A bare spawn is its OWN headless compositor: nothing on that route touches the desktop the box
+//! is showing, so on a KDE machine the physical panel keeps displaying the (idle) desktop for the
+//! whole stream — while the same `exclusive` policy on the KWin route turns the physicals off
+//! outright. The KWin route's mechanism is closed to us here: KWin refuses an output configuration
+//! with ZERO enabled outputs, and a gamescope session has no KWin output of its own to leave
+//! enabled. DPMS is the honest translation of `exclusive` for this route — the desktop stays
+//! exactly where it is (no topology churn, no window re-homing), the panels go dark, and any
+//! LOCAL input wakes them, which is the right answer for a desktop someone can walk up to.
+//! Stream input never wakes them: it is injected into the nested gamescope's own EIS socket and
+//! does not pass through KWin.
+//!
+//! Driven in-process over the compositor's own Wayland (`Connection::connect_to_env`, the same
+//! stack as [`crate::kwin_output_mgmt`] and for the same reason: `kscreen-doctor` rides a separate
+//! libkscreen/KDED layer that can be wedged while KWin itself answers fine), with a
+//! `kscreen-doctor --dpms` shell-out fallback. Best-effort everywhere — a box with no Wayland
+//! session, or a non-KDE desktop, declines quietly and the stream proceeds with the panel lit,
+//! exactly as before this module existed.
+//!
+//! **The hold is refcounted here, NOT floated through the registry's per-group restore.** Every
+//! gamescope spawn is its own display group (`registry::group_key` — deliberately, they are
+//! independent nested sessions), so the §6.1 group machinery alone would run the FIRST session's
+//! restore at that session's teardown and re-light the panel under a second, still-streaming
+//! session. Instead each exclusive spawn takes one [`acquire_stream_darken`] hold (the 0→1 edge
+//! darkens) and registers [`release_stream_darken`] as its per-display topology restore (the 1→0
+//! edge re-lights) — the same shape as `sleep_inhibit`'s refcount, riding the registry only for
+//! the *timing* of each release.
+//!
+//! Crash safety comes free: DPMS is non-persistent, so a host that dies holding the panel dark
+//! leaves nothing to journal — the screen re-lights on the next local input or compositor
+//! restart. (Contrast the Windows `pnp_disable_monitors` path, which needs a recovery journal
+//! precisely because its disable survives everything.)
+
+use std::collections::HashMap;
+use std::os::fd::{AsFd, AsRawFd};
+use std::sync::Mutex;
+use std::time::{Duration, Instant};
+use wayland_client::protocol::wl_callback::{self, WlCallback};
+use wayland_client::protocol::wl_output::{self, WlOutput};
+use wayland_client::protocol::wl_registry::{self, WlRegistry};
+use wayland_client::{Connection, Dispatch, Proxy, QueueHandle};
+
+// Client bindings for the vendored KDE dpms protocol (`protocols/dpms.xml`), generated inline like
+// the two in `kwin_output_mgmt`. Self-contained: its only foreign object type is the core
+// `wl_output`, which `wayland_client::protocol` already provides.
+#[allow(clippy::all, dead_code, non_camel_case_types, non_snake_case, unused)]
+pub mod protocol {
+    use wayland_client;
+    use wayland_client::protocol::*;
+
+    pub mod __interfaces {
+        use wayland_client::protocol::__interfaces::*;
+        wayland_scanner::generate_interfaces!("protocols/dpms.xml");
+    }
+    use self::__interfaces::*;
+
+    wayland_scanner::generate_client_code!("protocols/dpms.xml");
+}
+
+use protocol::org_kde_kwin_dpms::{Event as DpmsEvent, OrgKdeKwinDpms as Dpms};
+use protocol::org_kde_kwin_dpms_manager::OrgKdeKwinDpmsManager as DpmsManager;
+
+// The wire enum `org_kde_kwin_dpms.mode`. The XML types the `mode` request/event args as plain
+// `uint` (no `enum=` attribute), so the generated signatures take/deliver `u32` — these constants
+// are the protocol's values, kept in sync with the vendored `dpms.xml`.
+const DPMS_MODE_ON: u32 = 0;
+const DPMS_MODE_OFF: u32 = 3;
+
+/// `org_kde_kwin_dpms_manager` is a frozen v1 protocol (its own header warns it may change
+/// without a version bump, but no v2 has appeared since 2015); bind `min(advertised, 1)`.
+const MANAGER_MAX: u32 = 1;
+/// `wl_output.name` — the connector name used for logging — arrived in v4. Everything else we do
+/// works at v1, so a lower advert just costs the log its names.
+const WL_OUTPUT_MAX: u32 = 4;
+
+/// Overall budget for one darken/re-light operation (mirrors `kwin_output_mgmt::OP_BUDGET`):
+/// generous next to a healthy roundtrip, and only there so a wedged compositor can't pin the
+/// session-create (or group-teardown) thread.
+const OP_BUDGET: Duration = Duration::from_secs(3);
+
+/// Poll slice while waiting on the Wayland fd (matches `kwin_output_mgmt`).
+const POLL_MS: i32 = 100;
+
+/// One output's accumulated state on this connection, keyed by its `wl_output` global name.
+#[derive(Default)]
+struct OutputState {
+    proxy: Option<WlOutput>,
+    /// Connector name (`DP-1`) from `wl_output.name` (v4) — logging only; the global number is
+    /// the address everything operates on.
+    connector: Option<String>,
+    dpms: Option<Dpms>,
+    /// `org_kde_kwin_dpms.supported` — `None` until the bind burst arrives.
+    supported: Option<bool>,
+    /// The last `org_kde_kwin_dpms.mode` seen — kept current, so the post-`set` wait can watch it
+    /// flip.
+    mode: Option<u32>,
+}
+
+/// Everything one connection's queue accumulates.
+#[derive(Default)]
+struct State {
+    manager: Option<DpmsManager>,
+    /// Keyed by the `wl_output` GLOBAL NAME — a stable address for the compositor's lifetime, and
+    /// the identity the darken records so the re-light (a separate, later connection) can find the
+    /// same outputs again.
+    outputs: HashMap<u32, OutputState>,
+    /// Highest `wl_callback` serial whose `done` has arrived — the barrier the pump waits on.
+    sync_done: u32,
+}
+
+impl Dispatch<WlRegistry, ()> for State {
+    fn event(
+        state: &mut Self,
+        registry: &WlRegistry,
+        event: wl_registry::Event,
+        _: &(),
+        _: &Connection,
+        qh: &QueueHandle<Self>,
+    ) {
+        match event {
+            wl_registry::Event::Global {
+                name,
+                interface,
+                version,
+            } => {
+                if interface == DpmsManager::interface().name {
+                    let v = version.min(MANAGER_MAX);
+                    state.manager = Some(registry.bind::<DpmsManager, _, _>(name, v, qh, ()));
+                } else if interface == WlOutput::interface().name {
+                    let v = version.min(WL_OUTPUT_MAX);
+                    // The global name rides in the UserData so the output's own events (and the
+                    // dpms object's, which gets the same stamp) can find this entry.
+                    let out = registry.bind::<WlOutput, _, _>(name, v, qh, name);
+                    state.outputs.entry(name).or_default().proxy = Some(out);
+                }
+            }
+            // An output unplugged mid-operation: drop the entry so we never `set` on its corpse.
+            wl_registry::Event::GlobalRemove { name } => {
+                state.outputs.remove(&name);
+            }
+            _ => {}
+        }
+    }
+}
+
+impl Dispatch<WlOutput, u32> for State {
+    fn event(
+        state: &mut Self,
+        _: &WlOutput,
+        event: wl_output::Event,
+        global: &u32,
+        _: &Connection,
+        _: &QueueHandle<Self>,
+    ) {
+        if let wl_output::Event::Name { name } = event {
+            if let Some(o) = state.outputs.get_mut(global) {
+                o.connector = Some(name);
+            }
+        }
+    }
+}
+
+impl Dispatch<Dpms, u32> for State {
+    fn event(
+        state: &mut Self,
+        _: &Dpms,
+        event: DpmsEvent,
+        global: &u32,
+        _: &Connection,
+        _: &QueueHandle<Self>,
+    ) {
+        let Some(o) = state.outputs.get_mut(global) else {
+            return;
+        };
+        match event {
+            DpmsEvent::Supported { supported } => o.supported = Some(supported != 0),
+            DpmsEvent::Mode { mode } => o.mode = Some(mode),
+            DpmsEvent::Done => {}
+        }
+    }
+}
+
+// The manager has no events; the impl exists because `WlRegistry::bind` demands one.
+impl Dispatch<DpmsManager, ()> for State {
+    fn event(
+        _: &mut Self,
+        _: &DpmsManager,
+        _: protocol::org_kde_kwin_dpms_manager::Event,
+        _: &(),
+        _: &Connection,
+        _: &QueueHandle<Self>,
+    ) {
+    }
+}
+
+impl Dispatch<WlCallback, u32> for State {
+    fn event(
+        state: &mut Self,
+        _: &WlCallback,
+        event: wl_callback::Event,
+        serial: &u32,
+        _: &Connection,
+        _: &QueueHandle<Self>,
+    ) {
+        if let wl_callback::Event::Done { .. } = event {
+            state.sync_done = state.sync_done.max(*serial);
+        }
+    }
+}
+
+/// Why [`Session::open`] declined — the same honest-decline discipline as
+/// `kwin_output_mgmt::OpenFailure`: which rung said no decides both the log level and whether the
+/// `kscreen-doctor` fallback is worth attempting.
+enum OpenFailure {
+    /// No Wayland connection at all (`WAYLAND_DISPLAY` unset/stale). The common case for the bare
+    /// spawn's natural habitat — a headless plain-distro box with no desktop to darken.
+    Connect(String),
+    /// The compositor accepted the connection but did not answer the registry barrier in budget:
+    /// a live but wedged session — the case the shell-out fallback exists for.
+    RegistryBarrier,
+    /// Connected and answering, but `org_kde_kwin_dpms_manager` is not advertised — not KWin. A
+    /// definitive answer: no fallback can succeed here either (`kscreen-doctor` drives the same
+    /// KDE-only machinery), so this rung declines without one.
+    NoDpmsGlobal,
+    /// The manager is there but the per-output DPMS state bursts never completed in budget.
+    StateBarrier,
+}
+
+impl std::fmt::Display for OpenFailure {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            OpenFailure::Connect(e) => write!(f, "no Wayland connection ({e})"),
+            OpenFailure::RegistryBarrier => {
+                write!(
+                    f,
+                    "the compositor did not answer the registry roundtrip in budget"
+                )
+            }
+            OpenFailure::NoDpmsGlobal => {
+                write!(f, "org_kde_kwin_dpms_manager is not advertised (not KWin)")
+            }
+            OpenFailure::StateBarrier => {
+                write!(
+                    f,
+                    "the outputs' DPMS state never finished announcing in budget"
+                )
+            }
+        }
+    }
+}
+
+/// A connected session with the manager bound and every output's DPMS state read.
+struct Session {
+    conn: Connection,
+    queue: wayland_client::EventQueue<State>,
+    state: State,
+    next_sync: u32,
+}
+
+impl Session {
+    /// [`Session::connect`] for the operation named by `op`, logging the decline at a level that
+    /// matches what it means: `Connect`/`NoDpmsGlobal` are the everyday non-KDE answers (most
+    /// bare-spawn boxes have no desktop at all) and log at debug; the two barrier failures mean a
+    /// LIVE session stopped answering — on a KDE box that is a panel left lit, so they warn.
+    fn open(op: &'static str) -> Result<Session, OpenFailure> {
+        let opened = Session::connect();
+        if let Err(reason) = &opened {
+            match reason {
+                OpenFailure::Connect(_) | OpenFailure::NoDpmsGlobal => {
+                    tracing::debug!(op, %reason, "KWin DPMS unavailable");
+                }
+                OpenFailure::RegistryBarrier | OpenFailure::StateBarrier => {
+                    tracing::warn!(
+                        op,
+                        %reason,
+                        "KWin DPMS: in-process path unavailable — falling back to kscreen-doctor"
+                    );
+                }
+            }
+        }
+        opened
+    }
+
+    /// Connect to the desktop's Wayland socket, bind the dpms manager + every `wl_output`, create
+    /// a dpms status object per output and drain their state bursts — all bounded by [`OP_BUDGET`].
+    fn connect() -> Result<Session, OpenFailure> {
+        let conn = Connection::connect_to_env().map_err(|e| OpenFailure::Connect(e.to_string()))?;
+        let queue = conn.new_event_queue();
+        let qh = queue.handle();
+        let _registry = conn.display().get_registry(&qh, ());
+        let mut s = Session {
+            conn,
+            queue,
+            state: State::default(),
+            next_sync: 0,
+        };
+        let deadline = Instant::now() + OP_BUDGET;
+        // Phase 1: process the registry globals (binds the manager + every wl_output).
+        if !s.sync_barrier(deadline) {
+            return Err(OpenFailure::RegistryBarrier);
+        }
+        let Some(mgr) = s.state.manager.clone() else {
+            return Err(OpenFailure::NoDpmsGlobal);
+        };
+        // Phase 2: one dpms status object per output (stamped with the output's global name so its
+        // events land on the right entry), then a barrier that drains both the outputs' `name`
+        // events and the dpms objects' supported/mode/done bursts.
+        let qh = s.queue.handle();
+        let bound: Vec<(u32, WlOutput)> = s
+            .state
+            .outputs
+            .iter()
+            .filter_map(|(g, o)| o.proxy.clone().map(|p| (*g, p)))
+            .collect();
+        for (global, out) in bound {
+            let d = mgr.get(&out, &qh, global);
+            if let Some(o) = s.state.outputs.get_mut(&global) {
+                o.dpms = Some(d);
+            }
+        }
+        if !s.sync_barrier(deadline) {
+            return Err(OpenFailure::StateBarrier);
+        }
+        Ok(s)
+    }
+
+    /// Send a `wl_display.sync` and pump the queue until its `done` arrives or `deadline` passes.
+    fn sync_barrier(&mut self, deadline: Instant) -> bool {
+        self.next_sync += 1;
+        let serial = self.next_sync;
+        let qh = self.queue.handle();
+        let _cb = self.conn.display().sync(&qh, serial);
+        self.pump_until(deadline, |st| st.sync_done >= serial)
+    }
+
+    /// Bounded manual event loop — flush, dispatch, poll the fd. Mirrors
+    /// `kwin_output_mgmt::Session::pump_until` (same rationale: `blocking_dispatch` can't be
+    /// interrupted, so the fd is polled in [`POLL_MS`] slices against `deadline`).
+    fn pump_until(&mut self, deadline: Instant, done: impl Fn(&State) -> bool) -> bool {
+        loop {
+            if done(&self.state) {
+                return true;
+            }
+            if self.queue.dispatch_pending(&mut self.state).is_err() {
+                return false;
+            }
+            if done(&self.state) {
+                return true;
+            }
+            if Instant::now() >= deadline {
+                return false;
+            }
+            if self.conn.flush().is_err() {
+                return false;
+            }
+            let Some(guard) = self.conn.prepare_read() else {
+                continue; // events already queued — loop dispatches them
+            };
+            let mut pfd = libc::pollfd {
+                fd: self.conn.as_fd().as_raw_fd(),
+                events: libc::POLLIN,
+                revents: 0,
+            };
+            let remaining = deadline.saturating_duration_since(Instant::now());
+            let timeout = (remaining.as_millis() as i32).clamp(0, POLL_MS);
+            // SAFETY: `&mut pfd` points at one live, fully-initialized `libc::pollfd` on the stack
+            // and the count `1` matches that single element, so `poll` reads `fd`/`events` and
+            // writes `revents` strictly within `pfd`. `pfd.fd` is the Wayland connection's fd,
+            // valid because `self.conn` (and the `prepare_read` guard) outlive the call. `poll`
+            // blocks up to `timeout` ms and writes only `revents`; `pfd` is a fresh local that
+            // aliases nothing.
+            let r = unsafe { libc::poll(&mut pfd, 1, timeout) };
+            if r > 0 && (pfd.revents & libc::POLLIN) != 0 {
+                let _ = guard.read();
+            } // else: timeout/signal — drop the guard, re-check the deadline
+        }
+    }
+
+    /// Request `target` on every DPMS-supporting output not already there — restricted to the
+    /// globals in `only` when given (the re-light path, which must touch ONLY what the darken
+    /// touched: a panel the USER had put to sleep before the stream is theirs to keep dark).
+    /// Returns the outputs actually asked to change, `(global, connector)`, then waits (within
+    /// budget) for each one's `mode` event to confirm — the protocol is explicit that `set` is a
+    /// request the compositor may decline, so the confirmation is watched and its absence logged
+    /// rather than assumed.
+    fn set_mode(&mut self, target: u32, only: Option<&[u32]>) -> Vec<(u32, Option<String>)> {
+        let deadline = Instant::now() + OP_BUDGET;
+        let mut touched: Vec<(u32, Option<String>)> = Vec::new();
+        for (global, o) in &self.state.outputs {
+            if only.is_some_and(|list| !list.contains(global)) {
+                continue;
+            }
+            if o.supported != Some(true) || o.mode == Some(target) {
+                continue;
+            }
+            if let Some(dpms) = &o.dpms {
+                dpms.set(target);
+                touched.push((*global, o.connector.clone()));
+            }
+        }
+        if touched.is_empty() {
+            return touched;
+        }
+        let want: Vec<u32> = touched.iter().map(|(g, _)| *g).collect();
+        // An output that vanished mid-wait (GlobalRemove pruned it) counts as settled — there is
+        // nothing left to flip.
+        let confirmed = self.pump_until(deadline, |st| {
+            want.iter()
+                .all(|g| st.outputs.get(g).is_none_or(|o| o.mode == Some(target)))
+        });
+        if !confirmed {
+            tracing::warn!(
+                outputs = ?touched,
+                target,
+                "KWin DPMS: the compositor did not confirm the mode change in budget (the \
+                 requests are flushed; it may still land, or KWin may have declined)"
+            );
+        }
+        touched
+    }
+}
+
+/// What the 0→1 darken actually achieved — the record the 1→0 re-light undoes. Which arm did the
+/// work matters: the two are undone through different doors.
+enum Darkened {
+    /// The in-process path turned these outputs off — `(wl_output global, connector)`. Global
+    /// names are stable for the compositor's lifetime, so a later connection re-lights exactly
+    /// these. If KWin restarted in between the names match nothing — and that is the CORRECT
+    /// no-op, because a fresh KWin brings its outputs up lit anyway.
+    Wayland(Vec<(u32, Option<String>)>),
+    /// The `kscreen-doctor --dpms off` fallback ran (it takes no per-output address, so the
+    /// re-light is the symmetric `--dpms on`).
+    Kscreen,
+}
+
+/// The host-wide darken hold — refcounted like `sleep_inhibit`: the 0→1 edge darkens, the 1→0
+/// edge re-lights, and everything between is bookkeeping. See the module docs for why the
+/// registry's per-group restore float can't provide this (every gamescope spawn is its own group).
+struct Holds {
+    count: u32,
+    /// What the 0→1 darken achieved, held until the 1→0 release undoes it. `None` while count > 0
+    /// means the darken found nothing to do (no KDE, panels already dark) — the release then has
+    /// nothing to undo, which is exactly right.
+    darkened: Option<Darkened>,
+}
+
+impl Holds {
+    /// Take a hold; `true` on the 0→1 edge — the caller darkens and [`record`](Self::record)s.
+    fn acquire_edge(&mut self) -> bool {
+        self.count += 1;
+        self.count == 1
+    }
+
+    /// Store the 0→1 darken's outcome.
+    fn record(&mut self, d: Option<Darkened>) {
+        self.darkened = d;
+    }
+
+    /// Drop a hold; `Some` on the 1→0 edge hands the caller the record to undo. A release with no
+    /// hold outstanding is a caller bug (an unbalanced restore) — logged, never underflowed.
+    fn release_edge(&mut self) -> Option<Darkened> {
+        if self.count == 0 {
+            tracing::warn!("KWin DPMS: release without a matching acquire (unbalanced restore)");
+            return None;
+        }
+        self.count -= 1;
+        if self.count == 0 {
+            self.darkened.take()
+        } else {
+            None
+        }
+    }
+}
+
+static HOLDS: Mutex<Holds> = Mutex::new(Holds {
+    count: 0,
+    darkened: None,
+});
+
+/// Take one darken hold for an exclusive-topology stream. The first hold turns the live KDE
+/// desktop's panels off (best-effort, bounded); later holds just count. Callers MUST balance each
+/// call with [`release_stream_darken`] — the gamescope backend does it by registering the release
+/// as the display's topology restore, so the registry runs it exactly once per display at
+/// teardown (§6.1).
+///
+/// The lock is deliberately held across the darken itself: a racing second acquire must queue
+/// behind it (and then see the recorded outcome), not observe a count of 2 with nothing darkened.
+/// Same discipline on the release side, which keeps a teardown-overlapping-connect sequence
+/// strictly ordered: re-light completes, then the new stream's darken runs.
+pub fn acquire_stream_darken() {
+    let mut h = HOLDS.lock().unwrap_or_else(|e| e.into_inner());
+    if h.acquire_edge() {
+        let d = darken();
+        h.record(d);
+    }
+}
+
+/// Drop one darken hold; the last one out re-lights whatever the first hold's darken achieved.
+pub fn release_stream_darken() {
+    let mut h = HOLDS.lock().unwrap_or_else(|e| e.into_inner());
+    if let Some(d) = h.release_edge() {
+        relight(d);
+    }
+}
+
+/// The 0→1 darken: in-process over `org_kde_kwin_dpms` first, `kscreen-doctor --dpms off` as the
+/// wedged-compositor fallback. `None` = nothing was darkened (no desktop, not KDE, panels already
+/// off, or every arm declined) — and therefore nothing to restore.
+fn darken() -> Option<Darkened> {
+    match Session::open("darken") {
+        Ok(mut s) => {
+            let touched = s.set_mode(DPMS_MODE_OFF, None);
+            if touched.is_empty() {
+                tracing::debug!(
+                    "KWin DPMS: no output to darken (none supported, or all already off)"
+                );
+                None
+            } else {
+                tracing::info!(
+                    outputs = ?touched,
+                    "KWin DPMS: desktop outputs off for the exclusive gamescope stream"
+                );
+                Some(Darkened::Wayland(touched))
+            }
+        }
+        // Definitive "not KDE" / "no desktop": no fallback can do better (kscreen-doctor drives
+        // the same KDE-only machinery), so decline quietly — already logged by `open`.
+        Err(OpenFailure::NoDpmsGlobal) | Err(OpenFailure::Connect(_)) => None,
+        // A live session that stopped answering: the standalone tool rides a different stack
+        // (libkscreen/KDED) and may still get through — the same rationale as `kwin.rs`'s
+        // kscreen fallbacks, honest-verdict discipline included.
+        Err(_) => match kscreen_dpms("off") {
+            Some(true) => {
+                tracing::info!(
+                    "KWin DPMS: desktop outputs off for the exclusive gamescope stream \
+                     (kscreen-doctor fallback)"
+                );
+                Some(Darkened::Kscreen)
+            }
+            // Killed at its budget — NOT a refusal: kscreen-doctor applies first and then waits
+            // on the compositor, so a loaded KWin routinely lands the change and still gets
+            // killed. Record the darken so the teardown re-light runs either way; a `--dpms on`
+            // against a lit panel is a no-op.
+            None => Some(Darkened::Kscreen),
+            Some(false) => {
+                tracing::warn!(
+                    "KWin DPMS: could not darken the desktop outputs for the exclusive topology \
+                     (in-process path and kscreen-doctor both declined) — the panel stays lit"
+                );
+                None
+            }
+        },
+    }
+}
+
+/// The 1→0 re-light. **This is the last line of defence for a dark monitor**, so every arm that
+/// gives up says so loudly (the same discipline as `kwin.rs::reenable_outputs_kscreen`) — a dark
+/// panel with no line in the log is the failure mode this chain exists to prevent. The worst case
+/// stays self-healing regardless: DPMS is non-persistent, and any local input wakes the panel.
+fn relight(d: Darkened) {
+    match d {
+        Darkened::Wayland(outputs) => {
+            let globals: Vec<u32> = outputs.iter().map(|(g, _)| *g).collect();
+            match Session::open("re-light") {
+                Ok(mut s) => {
+                    s.set_mode(DPMS_MODE_ON, Some(&globals));
+                    tracing::info!(outputs = ?outputs, "KWin DPMS: desktop outputs back on");
+                }
+                Err(_) => match kscreen_dpms("on") {
+                    Some(true) | None => {
+                        tracing::info!(
+                            "KWin DPMS: desktop outputs back on (kscreen-doctor fallback)"
+                        );
+                    }
+                    Some(false) => {
+                        tracing::error!(
+                            outputs = ?outputs,
+                            "KWin DPMS: could NOT re-light the desktop outputs (in-process \
+                             restore and kscreen-doctor both declined) — the panel stays dark \
+                             until local input wakes it"
+                        );
+                    }
+                },
+            }
+        }
+        Darkened::Kscreen => {
+            if kscreen_dpms("on") == Some(false) {
+                tracing::error!(
+                    "KWin DPMS: could NOT re-light the desktop outputs (kscreen-doctor refused \
+                     the --dpms on it earlier accepted the off for) — the panel stays dark until \
+                     local input wakes it"
+                );
+            }
+        }
+    }
+}
+
+/// `kscreen-doctor --dpms <on|off>` for its verdict, on `kwin.rs`'s shared budget and three-state
+/// convention (`Some(true)` ran and succeeded, `Some(false)` refused or unrunnable, `None` killed
+/// at the budget — which, for a tool that applies first and waits after, usually means it landed).
+fn kscreen_dpms(mode: &'static str) -> Option<bool> {
+    crate::kwin::kscreen_verdict(&["--dpms".to_string(), mode.to_string()])
+}
+
+#[cfg(test)]
+mod tests {
+    use super::{Darkened, Holds};
+
+    fn fresh() -> Holds {
+        Holds {
+            count: 0,
+            darkened: None,
+        }
+    }
+
+    #[test]
+    fn first_acquire_darkens_later_ones_count() {
+        let mut h = fresh();
+        assert!(h.acquire_edge(), "0→1 must darken");
+        h.record(Some(Darkened::Kscreen));
+        assert!(
+            !h.acquire_edge(),
+            "a second concurrent stream must not re-darken"
+        );
+        assert!(!h.acquire_edge());
+    }
+
+    #[test]
+    fn only_the_last_release_relights() {
+        let mut h = fresh();
+        assert!(h.acquire_edge());
+        h.record(Some(Darkened::Wayland(vec![(7, Some("DP-1".into()))])));
+        assert!(!h.acquire_edge());
+        // First release: a sibling still streams — the panel must stay dark.
+        assert!(h.release_edge().is_none());
+        // Last release hands back the record to undo.
+        let d = h.release_edge();
+        assert!(matches!(d, Some(Darkened::Wayland(v)) if v == vec![(7, Some("DP-1".into()))]));
+    }
+
+    #[test]
+    fn a_darken_that_did_nothing_restores_nothing() {
+        let mut h = fresh();
+        assert!(h.acquire_edge());
+        h.record(None); // no KDE / already dark: nothing was changed
+        assert!(h.release_edge().is_none(), "nothing to undo");
+        assert_eq!(h.count, 0);
+    }
+
+    #[test]
+    fn unbalanced_release_never_underflows() {
+        let mut h = fresh();
+        assert!(h.release_edge().is_none());
+        assert_eq!(h.count, 0, "count must not wrap");
+        // And the state machine still works afterwards.
+        assert!(h.acquire_edge());
+        h.record(Some(Darkened::Kscreen));
+        assert!(matches!(h.release_edge(), Some(Darkened::Kscreen)));
+    }
+
+    #[test]
+    fn a_full_cycle_rearms_the_darken() {
+        let mut h = fresh();
+        assert!(h.acquire_edge());
+        h.record(Some(Darkened::Kscreen));
+        assert!(h.release_edge().is_some());
+        // A later stream on the same host lifetime darkens again.
+        assert!(
+            h.acquire_edge(),
+            "the 0→1 edge must re-arm after a full cycle"
+        );
+    }
+}

crates/punktfunk-core/cbindgen.toml

@@ -17,7 +17,19 @@ parse_deps = false
 # imports and their #[repr(C)] structs into the header, where socklen_t/ssize_t/iovec/msghdr are
 # undefined and the C harness fails to compile: the Apple batched recv (transport/udp.rs
 # `recvmsg_x` + `MsghdrX`) and the Android bionic mmsg bindings (`android_mmsg` module).
-exclude = ["MsghdrX", "recvmsg_x", "mmsghdr", "sendmmsg", "recvmmsg"]
+#
+# `SOFT_LIMIT_KNEE` is host-side CAPTURE processing (the operator gain's soft knee, applied before
+# the encoder). No C embedder can act on it — they receive already-gained audio — so exporting it
+# would add a bare `#define` to the ABI surface, against R21 below, for a constant with no meaning
+# on that side of the boundary. Excluded rather than renamed: the header stays byte-identical.
+exclude = [
+    "MsghdrX",
+    "recvmsg_x",
+    "mmsghdr",
+    "sendmmsg",
+    "recvmmsg",
+    "SOFT_LIMIT_KNEE",
+]
 # Reached by no exported SIGNATURE, so cbindgen's sweep misses it — but a C embedder needs the
 # vocabulary: `punktfunk_connection_end_reason` writes one of these as a bare byte (deliberately,
 # so the JNI/Swift sides can marshal a `u8` rather than an enum), which without this would leave

crates/punktfunk-core/src/audio.rs

@@ -955,6 +955,68 @@ pub fn crossfade_drop(ring: &mut std::collections::VecDeque<f32>, drop: usize, f
     ring.drain(..drop);
 }
 
+/// Where [`apply_gain`]'s soft knee begins, in linear amplitude (≈ −3.1 dBFS). Below this the
+/// gained signal is passed through EXACTLY — a boost whose peaks never reach the knee is plain
+/// multiplication, sample for sample, so the limiter costs nothing on material that does not need
+/// it.
+pub const SOFT_LIMIT_KNEE: f32 = 0.7;
+
+/// Multiply `samples` by `gain`, bending anything that would overshoot full scale into a soft knee
+/// instead of slicing it flat.
+///
+/// **Why this is not a `clamp`.** The GameStream plane's gain was `(s * gain).clamp(-1.0, 1.0)`,
+/// which is a hard clip: the waveform's peaks are replaced by literal flat tops, and a flat top is
+/// a discontinuity in the first derivative. That radiates high-order harmonics — the harsher and
+/// more aliasing-prone the higher they go — which is why a field report of "+18 dB and everything
+/// warbles" is the expected outcome of that code and not a bug in anything downstream. Any operator
+/// who set `PUNKTFUNK_AUDIO_GAIN` much above ~1.5 was hearing this.
+///
+/// The curve here is `tanh`-based and chosen for three properties, in this order:
+///
+/// 1. **C¹-continuous at the knee.** The shaped branch's slope at `m == KNEE` is
+///    `(1-K) · sech²(0) · 1/(1-K) == 1`, exactly the slope of the linear branch it meets. There is
+///    no corner in the transfer curve, so the onset of limiting is not itself an audible event —
+///    the failure mode of a naïve piecewise limiter, which trades one discontinuity for another.
+/// 2. **Bounded by construction.** `tanh` is asymptotic to 1, so the output approaches but never
+///    exceeds full scale for any finite input, and `±inf` maps to `±1.0`. No sample can leave here
+///    out of range, which is what the encoder downstream assumes.
+/// 3. **Odd-symmetric.** `f(-x) == -f(x)`, so the distortion it does introduce is odd-harmonic and
+///    adds no DC offset — the benign, "saturating" flavour rather than the rectifying one.
+///
+/// Callers gate on `gain != 1.0`, so the default path is untouched and the wire stays byte-for-byte
+/// identical to a build without this. Note this is a WAVESHAPER, not a lookahead limiter: it is
+/// memoryless and therefore costs zero latency, which is the trade that makes it acceptable in the
+/// realtime encode path. It raises headroom; it does not raise *loudness* the way a compressor
+/// with a real time constant would, and it should not be sold as one.
+pub fn apply_gain(samples: &mut [f32], gain: f32) {
+    // Unity is a no-op, not "multiply by one and shape": the shaper is only correct to apply to a
+    // signal somebody asked to boost. Without this, calling at unity would bend every peak above
+    // the knee — a silent quality change for anyone who forgot to gate the call, and the reason
+    // the callers' `gain != 1.0` guards are a convenience rather than a load-bearing contract.
+    if gain == 1.0 {
+        return;
+    }
+    for s in samples {
+        *s = soft_limit(*s * gain);
+    }
+}
+
+/// The waveshaper behind [`apply_gain`]: identity below [`SOFT_LIMIT_KNEE`], asymptotic to ±1.0
+/// above it. Exposed so the clients can mirror the curve if they ever grow a gain of their own.
+pub fn soft_limit(x: f32) -> f32 {
+    let m = x.abs();
+    if m <= SOFT_LIMIT_KNEE {
+        return x;
+    }
+    let head = 1.0 - SOFT_LIMIT_KNEE;
+    let shaped = SOFT_LIMIT_KNEE + head * ((m - SOFT_LIMIT_KNEE) / head).tanh();
+    if x < 0.0 {
+        -shaped
+    } else {
+        shaped
+    }
+}
+
 // ---- per-platform channel-layout helpers (pure data; no platform deps) --------------------
 
 /// Windows `WAVEFORMATEXTENSIBLE.dwChannelMask` for the wire layout.
@@ -2432,4 +2494,77 @@ mod tests {
         assert!(s.audible_tail <= 4, "{s:?}");
         assert!(s.audible <= 12, "{s:?}");
     }
+
+    /// Unity must be bit-exact. The callers gate on `gain != 1.0` anyway, but if this ever stopped
+    /// holding, every default session's wire would shift and the "byte-for-byte identical" claim
+    /// the tier machinery rests on would quietly become false.
+    #[test]
+    fn unity_gain_is_bit_exact() {
+        let src: Vec<f32> = (0..512).map(|i| (i as f32 / 512.0) * 2.0 - 1.0).collect();
+        let mut got = src.clone();
+        apply_gain(&mut got, 1.0);
+        assert_eq!(got, src, "unity gain must not touch a single sample");
+    }
+
+    /// Below the knee the limiter is not in circuit at all: a boost whose peaks stay under
+    /// `SOFT_LIMIT_KNEE` must be plain multiplication, or quiet material pays for a limiter it
+    /// never needed.
+    #[test]
+    fn below_the_knee_is_plain_multiplication() {
+        let mut got = vec![0.0, 0.1, -0.2, 0.34, -0.05];
+        apply_gain(&mut got, 2.0);
+        for (i, (g, s)) in got.iter().zip([0.0f32, 0.1, -0.2, 0.34, -0.05]).enumerate() {
+            assert_eq!(*g, s * 2.0, "sample {i} must be untouched below the knee");
+        }
+    }
+
+    /// The property the hard `clamp` violated and this exists to restore: no input, however
+    /// absurdly gained, may leave the shaper out of range — and non-finite input must not escape
+    /// as something the encoder would choke on.
+    #[test]
+    fn nothing_escapes_full_scale() {
+        for gain in [1.5f32, 4.0, 8.0, 64.0, 1000.0] {
+            let mut got: Vec<f32> = (0..401).map(|i| (i as f32 - 200.0) / 200.0).collect();
+            apply_gain(&mut got, gain);
+            for s in &got {
+                assert!(s.abs() <= 1.0, "gain {gain} produced {s}");
+            }
+        }
+        assert_eq!(soft_limit(f32::INFINITY), 1.0);
+        assert_eq!(soft_limit(f32::NEG_INFINITY), -1.0);
+    }
+
+    /// Monotonic and odd-symmetric. Monotonicity is what keeps the shaper a limiter rather than a
+    /// fold-back distortion; odd symmetry is what keeps its harmonics benign and its DC at zero.
+    #[test]
+    fn the_curve_is_monotonic_and_odd() {
+        let mut prev = f32::NEG_INFINITY;
+        for i in 0..=4000 {
+            let x = (i as f32 - 2000.0) / 500.0; // -4.0 ..= 4.0
+            let y = soft_limit(x);
+            assert!(y >= prev, "not monotonic at {x}: {y} < {prev}");
+            prev = y;
+            assert!(
+                (soft_limit(-x) + y).abs() < 1e-6,
+                "not odd-symmetric at {x}"
+            );
+        }
+    }
+
+    /// The knee must not itself be an audible event. Both branches meet at the same value AND the
+    /// same slope, so the transfer curve has no corner — a piecewise limiter that gets this wrong
+    /// just swaps the clip's discontinuity for a softer one.
+    #[test]
+    fn the_knee_has_no_corner() {
+        let k = SOFT_LIMIT_KNEE;
+        assert!((soft_limit(k) - k).abs() < 1e-6, "value jumps at the knee");
+        let h = 1e-4;
+        let below = (soft_limit(k) - soft_limit(k - h)) / h;
+        let above = (soft_limit(k + h) - soft_limit(k)) / h;
+        assert!((below - 1.0).abs() < 1e-2, "linear side slope {below}");
+        assert!(
+            (above - below).abs() < 1e-2,
+            "slope jumps at the knee: {below} -> {above}"
+        );
+    }
 }

crates/punktfunk-host/src/audio.rs

@@ -13,6 +13,54 @@ pub const SAMPLE_RATE: u32 = 48_000;
 /// Stereo channel count — the default and the punktfunk/1 audio plane's fixed layout.
 pub const CHANNELS: usize = 2;
 
+/// Highest boost `PUNKTFUNK_AUDIO_GAIN` will honour (+18 dB). Past this the soft knee is doing
+/// essentially all the work and the result is a squashed signal, not a louder one — so a runaway
+/// value (a stray `180` for `1.8`) is capped and said out loud rather than silently shipped.
+const MAX_CAPTURE_GAIN: f32 = 8.0;
+
+/// The operator's capture gain, shared by BOTH audio planes (`PUNKTFUNK_AUDIO_GAIN`, default
+/// `1.0` = untouched).
+///
+/// **Why the host needs one at all.** WASAPI loopback is tapped UPSTREAM of the endpoint's master
+/// volume, so turning the host's speaker slider up does nothing whatsoever to the level a client
+/// receives. Before this, the native `punktfunk/1` plane had no gain of any kind, which left no
+/// host-side way to raise a quiet desktop mix — the GameStream plane's knob was the only one, and
+/// it applied to the wrong protocol.
+///
+/// Applied through [`punktfunk_core::audio::apply_gain`], whose soft knee replaces the hard
+/// `clamp(-1.0, 1.0)` this used to be. That clamp is why boosting was a trap: it flat-tops peaks,
+/// and flat tops are audible as harsh distortion long before the operator reaches the level they
+/// were chasing.
+///
+/// ⚠ This is headroom, not loudness. It cannot close a peak-to-loudness gap against
+/// already-limited broadcast content — that needs a real compressor with a time constant, which is
+/// deliberately NOT what this is.
+pub fn capture_gain() -> f32 {
+    let raw: f32 = std::env::var("PUNKTFUNK_AUDIO_GAIN")
+        .ok()
+        .and_then(|v| v.parse().ok())
+        .unwrap_or(1.0);
+    // A negative or non-finite gain is a typo, never an intent: it would invert or poison every
+    // sample. Fall back to unity rather than shipping it.
+    if !raw.is_finite() || raw <= 0.0 {
+        if std::env::var("PUNKTFUNK_AUDIO_GAIN").is_ok() {
+            tracing::warn!(
+                "PUNKTFUNK_AUDIO_GAIN must be a positive number (1.0 = unchanged) — ignoring"
+            );
+        }
+        return 1.0;
+    }
+    if raw > MAX_CAPTURE_GAIN {
+        tracing::warn!(
+            requested = raw,
+            capped = MAX_CAPTURE_GAIN,
+            "PUNKTFUNK_AUDIO_GAIN is above the +18 dB ceiling — capping"
+        );
+        return MAX_CAPTURE_GAIN;
+    }
+    raw
+}
+
 /// Produces interleaved `f32` PCM at [`SAMPLE_RATE`] in the channel count it was opened
 /// with. Lives on its own thread; never blocks the capture loop (drops if the consumer
 /// falls behind).

crates/punktfunk-host/src/gamestream/audio.rs

@@ -397,11 +397,9 @@ fn audio_body(
     // stays small.
     let start = Instant::now();
     let mut frame_no: u64 = 0;
-    // Optional linear gain for quiet capture sources (PUNKTFUNK_AUDIO_GAIN, default 1.0).
-    let gain: f32 = std::env::var("PUNKTFUNK_AUDIO_GAIN")
-        .ok()
-        .and_then(|v| v.parse().ok())
-        .unwrap_or(1.0);
+    // Optional gain for quiet capture sources (PUNKTFUNK_AUDIO_GAIN, default 1.0). Soft-limited
+    // rather than clamped — see `crate::audio::capture_gain`.
+    let gain = crate::audio::capture_gain();
     tracing::info!(
         channels = layout.channels,
         streams = layout.streams,
@@ -418,9 +416,7 @@ fn audio_body(
         while acc.len() >= frame_len {
             let mut frame: Vec<f32> = acc.drain(..frame_len).collect();
             if gain != 1.0 {
-                for s in &mut frame {
-                    *s = (*s * gain).clamp(-1.0, 1.0);
-                }
+                punktfunk_core::audio::apply_gain(&mut frame, gain);
             }
             let n = enc.encode_float(&frame, &mut out)?;
             // AES-128-CBC the Opus payload (RTP header stays plaintext). Per-packet IV =

crates/punktfunk-host/src/library/custom.rs

@@ -442,6 +442,35 @@ pub fn validate_store_claim(store: &str) -> Result<(), String> {
     }
 }
 
+/// Drop every `launcher_ui` entry naming a launcher this host cannot actually open, returning the
+/// `(title, value)` pairs removed.
+///
+/// The launch-side counterpart to [`sanitize_art_paths`], and it exists for the same reason: a
+/// plugin reconciles its **whole** entry set at once, so anything that fails the payload costs the
+/// operator every game in it. The Playnite plugin appends one launcher tile beside the games, so a
+/// host that could not resolve `Playnite.FullscreenApp.exe` refused the lot — the operator saw an
+/// empty grid and a `HostRequestError` naming `entries[9]`, with nothing to say the other entries
+/// were fine.
+///
+/// Only the *unresolvable* case is dropped. A value outside the platform's vocabulary is still a
+/// hard 400 in [`validate_provider_payload`]: that one is a bug in the plugin, and silently
+/// swallowing it would leave the author with a tile that never appears and no reason why.
+///
+/// Dropping the whole entry rather than clearing its `launch` is deliberate — a launcher tile with
+/// no launch is a dead tile, which is strictly worse than no tile.
+pub fn sanitize_launcher_entries(inputs: &mut Vec<ProviderEntryInput>) -> Vec<(String, String)> {
+    let mut dropped = Vec::new();
+    inputs.retain(|e| {
+        let Some(launch) = &e.launch else { return true };
+        if launch.kind != "launcher_ui" || resolvable_launcher_ui(&launch.value) {
+            return true;
+        }
+        dropped.push((e.title.clone(), launch.value.clone()));
+        false
+    });
+    dropped
+}
+
 /// Validate a reconcile payload: non-empty titles and unique, non-empty external ids (the
 /// diff key — a duplicate would make ownership of the surviving entry ambiguous).
 pub fn validate_provider_payload(inputs: &[ProviderEntryInput]) -> Result<(), String> {
@@ -467,12 +496,13 @@ pub fn validate_provider_payload(inputs: &[ProviderEntryInput]) -> Result<(), St
                     "entries[{i}]: `launch.value` for kind `steam_ui` must be `bigpicture` or `desktop`"
                 ));
             }
-            // Refused rather than silently accepted, because the failure is otherwise invisible
-            // until a user clicks the tile: an unresolvable value yields no command at launch time.
-            if launch.kind == "launcher_ui" && !valid_launcher_ui(&launch.value) {
+            // Only the VOCABULARY is refused here. Whether the launcher is actually installed on
+            // this box is not the payload's fault, and 400ing over it threw away every game in the
+            // reconcile — see `sanitize_launcher_entries`, which drops just the tile instead.
+            if launch.kind == "launcher_ui" && !known_launcher_ui(&launch.value) {
                 return Err(format!(
-                    "entries[{i}]: `launch.value` for kind `launcher_ui` names a launcher this host \
-                     cannot open (`{}`)",
+                    "entries[{i}]: `launch.value` for kind `launcher_ui` is not a launcher this \
+                     host's platform supports (`{}`)",
                     launch.value
                 ));
             }
@@ -1065,6 +1095,14 @@ mod tests {
         // Other kinds are unconstrained here (the host validates them per-kind at launch).
         assert!(validate_provider_payload(&[with_launch("command", "anything")]).is_ok());
 
+        // `launcher_ui` is checked for VOCABULARY only. A launcher that is merely not installed
+        // must pass here and be dropped later — see `an_unopenable_launcher_tile_costs_only_itself`.
+        assert!(validate_provider_payload(&[with_launch("launcher_ui", "nonesuch")]).is_err());
+        #[cfg(windows)]
+        assert!(validate_provider_payload(&[with_launch("launcher_ui", "playnite")]).is_ok());
+        #[cfg(target_os = "linux")]
+        assert!(validate_provider_payload(&[with_launch("launcher_ui", "lutris")]).is_ok());
+
         let with_env = |key: &str, value: Option<&str>| {
             let mut i = input("a", "A");
             i.detect.env_marker = Some(EnvMarker {
@@ -1129,4 +1167,40 @@ mod tests {
             "duplicate external_id"
         );
     }
+
+    /// The regression `sanitize_launcher_entries` exists for: a launcher tile this host cannot open
+    /// must cost that tile, not the games reconciled beside it.
+    ///
+    /// Field shape — the Playnite plugin appends exactly one `launcher_ui` tile after its games, so
+    /// `entries[N]` failing validation used to refuse the entire payload and leave the operator with
+    /// an empty grid and a `HostRequestError` that named only the index.
+    #[test]
+    fn an_unopenable_launcher_tile_costs_only_itself() {
+        let mut tile = input("launcher", "Playnite");
+        tile.role = GameRole::Launcher;
+        tile.launch = Some(LaunchSpec {
+            kind: "launcher_ui".into(),
+            value: "playnite".into(),
+        });
+
+        let mut inputs = vec![input("a", "A"), tile, input("b", "B")];
+        let dropped = sanitize_launcher_entries(&mut inputs);
+
+        if resolvable_launcher_ui("playnite") {
+            // A Windows box with Playnite actually installed keeps all three.
+            assert!(dropped.is_empty());
+            assert_eq!(inputs.len(), 3);
+        } else {
+            // Everywhere else the tile goes and both games survive — the whole point of the split.
+            assert_eq!(dropped.len(), 1);
+            assert_eq!(dropped[0].1, "playnite");
+            assert_eq!(inputs.len(), 2);
+            assert!(inputs.iter().all(|e| e.external_id != "launcher"));
+        }
+
+        // A payload of nothing but games is untouched on every OS.
+        let mut only_games = vec![input("a", "A"), input("b", "B")];
+        assert!(sanitize_launcher_entries(&mut only_games).is_empty());
+        assert_eq!(only_games.len(), 2);
+    }
 }

crates/punktfunk-host/src/library/launch.rs

@@ -478,13 +478,31 @@ fn launcher_ui_stores() -> &'static [&'static str] {
     }
 }
 
-/// Is this a `launcher_ui` value this host can resolve?
+/// Is `value` a launcher this host's platform knows about at all?
 ///
-/// On Windows, Playnite is validated by *resolution* rather than by being on the list: a host
-/// without Playnite installed refuses the entry (a 400 the plugin author can act on) instead of
-/// publishing a tile that does nothing when a user clicks it.
-pub(crate) fn valid_launcher_ui(value: &str) -> bool {
-    if !launcher_ui_stores().contains(&value) {
+/// The *vocabulary* half of the old `valid_launcher_ui`. A value outside this set is a plugin
+/// author's mistake — a typo, or a launcher this OS has no support for — and no amount of
+/// installing things on the box will make it resolve, so the reconcile refuses the payload.
+pub(crate) fn known_launcher_ui(value: &str) -> bool {
+    launcher_ui_stores().contains(&value)
+}
+
+/// Can this host open `value`'s launcher **right now**?
+///
+/// The *environment* half. Deliberately separate from [`known_launcher_ui`], because the two
+/// failures are not the same kind of thing and must not get the same answer:
+///
+/// - an unknown value is a bug in the plugin, and a 400 is the only way its author finds out;
+/// - a known value that will not resolve means the launcher simply is not installed here, which is
+///   an ordinary fact about the box, not a defect in the payload.
+///
+/// Conflating them cost a real library: the Playnite plugin publishes one launcher tile alongside
+/// every game, so a host that could not resolve Playnite 400'd the whole reconcile and the operator
+/// got **no games at all** — the same shape as the unservable-cover bug that
+/// [`super::sanitize_art_paths`] was introduced to fix. The tile is dropped now (see
+/// [`super::sanitize_launcher_entries`]) and the games sync.
+pub(crate) fn resolvable_launcher_ui(value: &str) -> bool {
+    if !known_launcher_ui(value) {
         return false;
     }
     #[cfg(windows)]
@@ -502,36 +520,141 @@ pub(crate) fn valid_launcher_ui(value: &str) -> bool {
 /// directly, which is also why nothing here is interpolated from the entry: the whole value is the
 /// literal `"playnite"`.
 ///
-/// Playnite installs per-user by default, so the install directory comes from its own uninstall
-/// entry (HKCU first, then HKLM for a machine-wide install), falling back to the default
-/// `%LOCALAPPDATA%\Playnite`. `None` when nothing resolves, which is what refuses the tile.
+/// `None` when nothing resolves, which is what drops the tile.
 #[cfg(windows)]
 fn playnite_fullscreen_exe() -> Option<std::path::PathBuf> {
-    use winreg::enums::{HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE};
-    use winreg::RegKey;
-    const KEY: &str = r"SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\Playnite";
     const EXE: &str = "Playnite.FullscreenApp.exe";
-
-    let from_registry = [HKEY_CURRENT_USER, HKEY_LOCAL_MACHINE]
+    playnite_install_dirs()
         .into_iter()
-        .find_map(|root| {
-            RegKey::predef(root)
-                .open_subkey(KEY)
-                .ok()?
-                .get_value::<String, _>("InstallLocation")
-                .ok()
-        })
-        .map(std::path::PathBuf::from);
-
-    from_registry
-        .into_iter()
-        .chain(
-            std::env::var_os("LOCALAPPDATA").map(|l| std::path::PathBuf::from(l).join("Playnite")),
-        )
         .map(|dir| dir.join(EXE))
         .find(|p| p.is_file())
 }
 
+/// Windows: every directory that might hold a Playnite install, best candidates first.
+///
+/// **Playnite installs per-user by default, and this host is a LocalSystem service** — which
+/// invalidates all three of the obvious lookups, and is why this is not a two-liner:
+///
+/// - `HKEY_CURRENT_USER` is *SYSTEM's own* hive (`S-1-5-18`), never the person's, so a per-user
+///   install is invisible there. Every **loaded** hive under `HKEY_USERS` is read instead: only
+///   logged-on users' hives are loaded, which is exactly the set that can be streaming, and it
+///   avoids a `WTSQueryUserToken` dance for what is a best-effort probe. Same trade-off
+///   [`crate::procscan::steam_running_hint`] makes, for the same reason.
+/// - The uninstall subkey is matched by its **`DisplayName`**, not by key name. Playnite ships an
+///   Inno Setup installer and Inno registers `<AppId>_is1` — measured on a Windows box where Git
+///   and Inno itself appear as `Git_is1` and `Inno Setup 6_is1`. The hardcoded
+///   `…\Uninstall\Playnite` this replaced matched nothing on any box.
+/// - `%LOCALAPPDATA%` for a SYSTEM service is `C:\Windows\System32\config\systemprofile\AppData\
+///   Local`, so the default-install fallback cannot trust the variable — it enumerates the profiles
+///   under the users base instead, the same breadth [`super::art::art_roots`] already allows.
+///
+/// Order matters only as a preference: a registry `InstallLocation` is what the installer actually
+/// did, so it is consulted before the conventional path. Every candidate is probed for the exe, so
+/// a stale entry costs one `is_file` and nothing else.
+#[cfg(windows)]
+fn playnite_install_dirs() -> Vec<std::path::PathBuf> {
+    use winreg::enums::{HKEY_LOCAL_MACHINE, HKEY_USERS, KEY_READ};
+    use winreg::RegKey;
+
+    // 64-bit and 32-bit views. HKCU/HKU `Software` is not redirected (only `Software\Classes` is),
+    // so the WOW view is a machine-hive concern only.
+    const UNINSTALL: &str = r"Software\Microsoft\Windows\CurrentVersion\Uninstall";
+    const UNINSTALL_WOW: &str = r"Software\WOW6432Node\Microsoft\Windows\CurrentVersion\Uninstall";
+
+    let mut dirs: Vec<std::path::PathBuf> = Vec::new();
+
+    let hklm = RegKey::predef(HKEY_LOCAL_MACHINE);
+    playnite_dirs_from_uninstall(&hklm, UNINSTALL, &mut dirs);
+    playnite_dirs_from_uninstall(&hklm, UNINSTALL_WOW, &mut dirs);
+
+    let users = RegKey::predef(HKEY_USERS);
+    for sid in users.enum_keys().flatten() {
+        // The `…_Classes` companion hives carry file associations, never uninstall entries.
+        if sid.ends_with("_Classes") {
+            continue;
+        }
+        if let Ok(hive) = users.open_subkey_with_flags(&sid, KEY_READ) {
+            playnite_dirs_from_uninstall(&hive, UNINSTALL, &mut dirs);
+        }
+    }
+
+    // The conventional per-user location, for every profile on the box — this is where Playnite's
+    // own default install lands, and it covers a user whose hive is not currently loaded.
+    for profile in windows_user_profiles() {
+        push_unique(&mut dirs, profile.join(r"AppData\Local\Playnite"));
+    }
+    dirs
+}
+
+/// Collect `InstallLocation` from every Playnite-looking uninstall entry under `root\path`.
+///
+/// Matched on `DisplayName` because the key name is the installer's `AppId` (see
+/// [`playnite_install_dirs`]). `starts_with` rather than equality so a versioned or suffixed display
+/// name still counts; the value is only ever used as a directory to probe for the exe, so a false
+/// positive costs one failed `is_file`.
+#[cfg(windows)]
+fn playnite_dirs_from_uninstall(
+    root: &winreg::RegKey,
+    path: &str,
+    out: &mut Vec<std::path::PathBuf>,
+) {
+    use winreg::enums::KEY_READ;
+
+    let Ok(uninstall) = root.open_subkey_with_flags(path, KEY_READ) else {
+        return;
+    };
+    for name in uninstall.enum_keys().flatten() {
+        let Ok(entry) = uninstall.open_subkey_with_flags(&name, KEY_READ) else {
+            continue;
+        };
+        let display: String = entry.get_value("DisplayName").unwrap_or_default();
+        if !display.starts_with("Playnite") {
+            continue;
+        }
+        if let Ok(location) = entry.get_value::<String, _>("InstallLocation") {
+            let location = location.trim();
+            if !location.is_empty() {
+                push_unique(out, std::path::PathBuf::from(location));
+            }
+        }
+    }
+}
+
+/// Every user profile directory on the box (`C:\Users\*`), minus the shared `Public` pseudo-profile.
+///
+/// `%PUBLIC%`'s parent is the users base on every supported Windows — the same derivation
+/// [`super::art::art_roots`] uses — with `%SystemDrive%\Users` as the fallback when the variable is
+/// missing from a service's environment.
+#[cfg(windows)]
+fn windows_user_profiles() -> Vec<std::path::PathBuf> {
+    let base = std::env::var_os("PUBLIC")
+        .map(std::path::PathBuf::from)
+        .and_then(|p| p.parent().map(std::path::Path::to_path_buf))
+        .or_else(|| {
+            std::env::var_os("SystemDrive").map(|d| std::path::PathBuf::from(d).join("Users"))
+        });
+    let Some(base) = base else {
+        return Vec::new();
+    };
+    let Ok(entries) = std::fs::read_dir(&base) else {
+        return Vec::new();
+    };
+    entries
+        .flatten()
+        .map(|e| e.path())
+        .filter(|p| p.is_dir() && !p.ends_with("Public"))
+        .collect()
+}
+
+/// Push `path` unless an equal one is already there — the candidate lists are a handful of entries,
+/// so a linear check beats carrying a set around.
+#[cfg(windows)]
+fn push_unique(out: &mut Vec<std::path::PathBuf>, path: std::path::PathBuf) {
+    if !out.contains(&path) {
+        out.push(path);
+    }
+}
+
 /// Map a `heroic` LaunchSpec value (`<runner>:<appName>`) to the Heroic launch command, run nested in
 /// gamescope. The host owns this mapping; the client only ever sends the id. CAVEAT: Heroic is a
 /// single-instance Electron app — in a fresh per-session gamescope it boots, launches the game (which
@@ -800,33 +923,38 @@ mod tests {
     fn launcher_ui_accepts_only_launchers_this_host_can_open() {
         #[cfg(target_os = "linux")]
         {
-            assert!(valid_launcher_ui("heroic"));
-            assert!(valid_launcher_ui("lutris"));
-            // Not wired on this OS — refused inbound rather than becoming a tile that does nothing.
-            assert!(!valid_launcher_ui("gog"));
+            assert!(known_launcher_ui("heroic"));
+            assert!(known_launcher_ui("lutris"));
+            // Not wired on this OS — outside the vocabulary, so it is refused inbound rather than
+            // becoming a tile that does nothing.
+            assert!(!known_launcher_ui("gog"));
         }
         #[cfg(windows)]
         {
-            // Playnite is accepted only when this host can actually FIND its Fullscreen app:
-            // validation is resolution, so a box without Playnite refuses the entry rather than
-            // publishing a tile that does nothing when clicked.
+            // Playnite is in the vocabulary unconditionally — whether this particular box has it
+            // installed is a separate question, answered by `resolvable_launcher_ui` below. Keeping
+            // them separate is the fix for the reconcile that 400'd a whole library over one tile.
+            assert!(known_launcher_ui("playnite"));
             assert_eq!(
-                valid_launcher_ui("playnite"),
+                resolvable_launcher_ui("playnite"),
                 playnite_fullscreen_exe().is_some()
             );
             // The Linux launchers, and the Windows ones whose activation is still unverified
             // (Epic, GOG Galaxy, the Xbox app), stay refused.
-            assert!(!valid_launcher_ui("heroic"));
-            assert!(!valid_launcher_ui("gog"));
+            assert!(!known_launcher_ui("heroic"));
+            assert!(!known_launcher_ui("gog"));
         }
         #[cfg(not(any(target_os = "linux", windows)))]
         {
             // No launcher UIs are wired on this OS, so every value is refused.
-            assert!(!valid_launcher_ui("heroic"));
-            assert!(!valid_launcher_ui("gog"));
+            assert!(!known_launcher_ui("heroic"));
+            assert!(!known_launcher_ui("gog"));
         }
-        assert!(!valid_launcher_ui(""));
-        assert!(!valid_launcher_ui("lutris; rm -rf ~"));
+        // Junk is outside the vocabulary on every OS, so it never reaches a resolver.
+        assert!(!known_launcher_ui(""));
+        assert!(!known_launcher_ui("lutris; rm -rf ~"));
+        assert!(!resolvable_launcher_ui(""));
+        assert!(!resolvable_launcher_ui("lutris; rm -rf ~"));
     }
 
     /// The `xbox` kind is what a library PLUGIN can publish: the runner's principal cannot read

crates/punktfunk-host/src/mgmt/library.rs

@@ -524,6 +524,18 @@ pub(crate) async fn reconcile_provider_entries(
             return denied;
         }
     }
+    // A launcher this box cannot open is a fact about the box, not a defect in the payload, so it
+    // costs its own tile and nothing else. Before this, the Playnite plugin's single launcher entry
+    // 400'd every game it shipped alongside.
+    for (title, value) in crate::library::sanitize_launcher_entries(&mut inputs) {
+        tracing::warn!(
+            provider,
+            launcher = %value,
+            title = %title,
+            "library reconcile: dropped a launcher tile this host cannot open — the rest of the \
+             payload still syncs. Install the launcher, or turn the tile off in the plugin's config"
+        );
+    }
     // One aggregated line, not one per entry: a root mismatch misses EVERY cover in the payload, and
     // a per-entry warn would bury the rest of the log under a thousand copies of one fact.
     let mut dropped_art = 0usize;

crates/punktfunk-host/src/native/audio.rs

@@ -142,6 +142,20 @@ pub(super) fn audio_thread(
     };
 
     let frame_len = SAMPLES_PER_FRAME * want as usize;
+    // Operator capture gain, soft-limited (`PUNKTFUNK_AUDIO_GAIN`, default 1.0 = untouched). This
+    // plane had NO gain at all until now, so `PUNKTFUNK_AUDIO_GAIN` silently did nothing on
+    // punktfunk/1 while working on GameStream — and since WASAPI loopback taps upstream of the
+    // endpoint's master volume, there was no other host-side way to lift a quiet desktop mix.
+    // Read once per session rather than per frame: this is an operator setting, not a live control.
+    let gain = crate::audio::capture_gain();
+    if gain != 1.0 {
+        tracing::info!(
+            gain,
+            "audio: applying operator capture gain (soft-limited above \
+             {}; headroom, not loudness)",
+            punktfunk_core::audio::SOFT_LIMIT_KNEE
+        );
+    }
     let mut acc: Vec<f32> = Vec::with_capacity(frame_len * 4);
     // Sized for the largest surround frame (7.1 HQ ≈ 1.3 KB at 5 ms); ample for normal quality.
     let mut opus_buf = vec![0u8; 4096];
@@ -253,7 +267,10 @@ pub(super) fn audio_thread(
             }
             pace_due = Some(pace_due.unwrap_or_else(std::time::Instant::now) + FRAME_INTERVAL);
 
-            let frame: Vec<f32> = acc.drain(..frame_len).collect();
+            let mut frame: Vec<f32> = acc.drain(..frame_len).collect();
+            if gain != 1.0 {
+                punktfunk_core::audio::apply_gain(&mut frame, gain);
+            }
             let pts_ns = next_pts_ns;
             next_pts_ns += FRAME_MS as u64 * 1_000_000;
             match enc.encode_float(&frame, &mut opus_buf) {

crates/punktfunk-host/src/update/windows.rs

@@ -7,12 +7,20 @@
 //! 1. **SHA-256 == the signed manifest's** — the primary integrity gate (the manifest is the
 //!    Ed25519-verified document; this check makes the downloaded bytes those exact bytes).
 //! 2. **Authenticode**: the embedded signature must be cryptographically valid, tolerating
-//!    `CERT_E_UNTRUSTEDROOT` while the shipping cert is self-signed (`CN=unom`); when the
+//!    `CERT_E_UNTRUSTEDROOT` (canary and local builds still sign with a self-signed cert, and
+//!    releases moved to Azure Artifact Signing without needing this to tighten); when the
 //!    manifest carries leaf pins, the signing leaf's SHA-256 must match one. The leaf is taken
 //!    from the SAME `WinVerifyTrust` state (`WTHelperGetProvSignerFromChain`), never a second
 //!    parse — no verify-vs-inspect gap. An empty pin list skips only the pin comparison (the
-//!    manifest hash already binds content; pins arrive via `AUTHENTICODE_SHA256` in CI once
-//!    the cert story settles — the field exists so Trusted Signing is a manifest edit).
+//!    manifest hash already binds content).
+//!
+//!    **Leaf pinning cannot be used with Azure Artifact Signing.** That service mints a fresh leaf
+//!    per signing request, valid ~3 days, so an `AUTHENTICODE_SHA256` pin would go stale within days
+//!    of publishing and reject every subsequent release. (An earlier note here assumed the opposite —
+//!    that the pin field made Trusted Signing "a manifest edit". It does not.) If pinning is wanted
+//!    against the Azure-signed artifacts, pin something stable instead: the issuing intermediate, or
+//!    the certificate subject. Leave the list empty until then; the Ed25519-signed manifest hash is
+//!    what actually binds the downloaded bytes.
 //!
 //! The spawn uses `CREATE_BREAKAWAY_FROM_JOB`: the service worker's job object is kill-on-close
 //! (a stopping service would otherwise take the installer down with it) and was created
@@ -284,8 +292,10 @@ fn preflight_disk(at: &Path, needed: u64) -> Result<(), String> {
     Ok(())
 }
 
-/// Authenticode: valid embedded signature (untrusted root tolerated — self-signed `CN=unom`),
-/// signing-leaf SHA-256 ∈ `pins` when pins are present. The leaf comes out of the same
+/// Authenticode: valid embedded signature (untrusted root tolerated — canary/local builds are still
+/// self-signed), signing-leaf SHA-256 ∈ `pins` when pins are present — but see the module docs: a
+/// leaf pin is unusable against Azure-signed releases, whose leaf rotates every few days. The leaf
+/// comes out of the same
 /// `WinVerifyTrust` state via `WTHelperGetProvSignerFromChain`. (`pub(crate)`: the service
 /// supervisor's boot-loop rollback re-checks the cached previous installer with it.)
 pub(crate) fn verify_authenticode(path: &Path, pins: &[String]) -> Result<(), String> {

docs-site/content/docs/configuration.md

@@ -156,7 +156,7 @@ See your desktop page ([KDE](/docs/kde), [GNOME](/docs/gnome)) for when to set t
 |---|---|---|
 | `PUNKTFUNK_AUDIO_QUALITY` | `low` · `standard` · `high` *(default `high`)* | Desktop-audio encode quality. `high` (stereo 256 kbps Opus, effectively transparent) costs about 1 % of a normal video bitrate, so there's rarely a reason to go lower. `standard` is exactly the pre-0.25 encoder (stereo 128 kbps) — handy for an A/B comparison; `low` is for genuinely constrained links (noticeably lossy on music, still fine for game audio and voice). A typo warns in the log and keeps `high` rather than silently downgrading. Host-side only — clients play whatever arrives, no client setting involved. |
 | `PUNKTFUNK_AUDIO_REDUNDANCY` | `1` · `0` *(default: automatic)* | Send audio packets redundantly so a lossy link doesn't crackle. Leave it unset: the host turns redundancy on by itself, only toward clients that support it and only while the link is actually losing packets. `1` forces it on for the whole session, `0` never sends it. |
-| `PUNKTFUNK_AUDIO_GAIN` | float (default `1.0`) | **(Moonlight/GameStream sessions only)** Linear gain applied to captured desktop audio — bump it for a quiet source. The native `punktfunk/1` path ignores it; adjust the source's own volume there instead. |
+| `PUNKTFUNK_AUDIO_GAIN` | float (default `1.0`) | Gain applied to captured desktop audio — bump it for a quiet source. Applies to **both** the native `punktfunk/1` and Moonlight/GameStream paths. Peaks are rounded off by a soft limiter rather than clipped, so a boost distorts gracefully instead of abruptly; values above `8.0` (+18 dB) are capped, and a non-positive value is ignored. Note this buys **headroom, not loudness** — it cannot make a desktop mix as loud as already-limited streaming-app audio, and pushing it hard to try will audibly squash the signal. On Windows this is the only host-side control that works at all: loopback capture is tapped upstream of the endpoint's master volume, so the speaker slider does not affect what a client receives. |
 | `PUNKTFUNK_MIC_DEVICE` | name substring | **(Windows)** Target mic-uplink device by friendly-name substring (first match wins). |
 | `PUNKTFUNK_MIC_LEGACY_BUFFER` | `1` | Restore the fixed pre-adaptive mic buffering (a ~48 ms prime and ~120 ms cap on Windows; a buffer scaled to the recording app's audio quantum on Linux) instead of the adaptive per-client jitter target. One-release escape hatch: if the microphone coming out of the host only sounds right *with* this set, that's a bug — please report it. |
 | `PUNKTFUNK_NO_MIC_INSTALL` | set | **(Windows)** Skip installing the virtual-mic driver (e.g. when the host runs as SYSTEM). |

docs-site/package.json

@@ -10,30 +10,30 @@
     "lint": "tsc --noEmit"
   },
   "dependencies": {
-    "@fontsource-variable/geist": "^5.2.9",
-    "@scalar/api-reference-react": "^0.9.47",
-    "@tanstack/react-router": "^1.121.0",
-    "@tanstack/react-start": "^1.121.0",
-    "@unom/app-ui": "^0.1.0",
+    "@fontsource-variable/geist": "^5.3.0",
+    "@scalar/api-reference-react": "^0.9.63",
+    "@tanstack/react-router": "^1.170.28",
+    "@tanstack/react-start": "^1.168.45",
+    "@unom/app-ui": "^0.2.1",
     "@unom/style": "^0.4.4",
-    "@unom/ui": "^0.8.16",
-    "fumadocs-core": "^16.10.5",
-    "fumadocs-ui": "^16.10.5",
-    "react": "^19.0.0",
-    "react-dom": "^19.0.0"
+    "@unom/ui": "^0.9.2",
+    "fumadocs-core": "^16.14.4",
+    "fumadocs-ui": "^16.14.4",
+    "react": "^19.2.8",
+    "react-dom": "^19.2.8"
   },
   "devDependencies": {
-    "@tailwindcss/vite": "^4.0.0",
+    "@tailwindcss/vite": "^4.3.3",
     "@tanstack/nitro-v2-vite-plugin": "^1.155.0",
     "@types/mdx": "^2.0.14",
-    "@types/node": "^22.10.0",
-    "@types/react": "^19.0.0",
-    "@types/react-dom": "^19.0.0",
-    "@vitejs/plugin-react": "^5",
-    "fumadocs-mdx": "^15.0.12",
-    "tailwindcss": "^4.0.0",
-    "typescript": "^5.7.0",
-    "vite": "^7.3.5",
-    "vite-tsconfig-paths": "^5.1.0"
+    "@types/node": "^22.20.1",
+    "@types/react": "^19.2.18",
+    "@types/react-dom": "^19.2.4",
+    "@vitejs/plugin-react": "^5.2.0",
+    "fumadocs-mdx": "^15.2.3",
+    "tailwindcss": "^4.3.3",
+    "typescript": "^5.9.3",
+    "vite": "^7.3.6",
+    "vite-tsconfig-paths": "^5.1.4"
   }
 }

packaging/windows/README.md

@@ -140,8 +140,61 @@ fresh install uses the generated random console password — read it from
 > punktfunk-planning: `windows-build-and-packaging.md` (internal planning repo) for the toolchain
 > + signing details.
 
+## Installer signing (Azure Artifact Signing)
+
+`setup.exe`, `punktfunk-host.exe`, `punktfunk-tray.exe` and the Vulkan HDR layer are signed with
+**Azure Artifact Signing** (formerly Trusted Signing): account `unomsigning`, certificate profile
+`unom-io`, endpoint `https://neu.codesigning.azure.net/`. It is a publicly trusted CA, so users get
+a named publisher in the UAC prompt and there is no `.cer` to import — `HOST_CER_PATH` is simply not
+emitted in this mode (every consumer already guards on `Test-Path`).
+
+`pack-host-installer.ps1` resolves a backend in this order, first match wins:
+
+| order | backend | selected by |
+| --- | --- | --- |
+| 1 | Azure Artifact Signing | `AZURE_CODESIGNING_ENDPOINT` + `_ACCOUNT` + `_PROFILE` all set |
+| 2 | stable self-signed `.pfx` | `MSIX_CERT_PFX_B64` / `MSIX_CERT_PASSWORD` |
+| 3 | ephemeral self-signed | nothing set (canary / local only; a `v*` tag **fails closed**) |
+
+Credentials for mode 1 come from the environment via `DefaultAzureCredential` — `AZURE_TENANT_ID`,
+`AZURE_CLIENT_ID`, `AZURE_CLIENT_SECRET`, the `punktfunk-ci-signing` service principal. It holds
+exactly one role, *Artifact Signing Certificate Profile Signer*, scoped to the `unom-io` profile: it
+can sign and can do nothing else with the subscription. The script hard-fails if the trio is missing
+rather than letting `DefaultAzureCredential` fall through to an interactive login that would hang a
+runner forever.
+
+> **Timestamping is mandatory here, not best-effort.** Azure mints a leaf certificate per request,
+> valid for about three days. An untimestamped signature therefore goes untrusted within days of
+> release — it would verify fine on the runner and fail on users' machines that weekend. `Sign-File`
+> refuses to retry without a timestamp in Azure mode; modes 2 and 3 keep the old lenient retry, where
+> the cert outlives the release anyway.
+
+### Runner setup
+
+`signtool` reaches Azure through `Azure.CodeSigning.Dlib.dll`, which ships in the
+`Microsoft.Trusted.Signing.Client` NuGet package — no installer, no fixed path. On the Windows runner:
+
+```powershell
+nuget install Microsoft.Trusted.Signing.Client -OutputDirectory $env:USERPROFILE\.nuget\packages
+```
+
+`Find-AzureDlib` searches that path and `C:\trusted-signing\`, newest first, so a package update needs
+no script edit. Set `AZURE_CODESIGNING_DLIB` to override with an explicit path.
+
 ## Driver signing (`DRIVER_CERT_PFX_B64`)
 
+> **The drivers are deliberately NOT on Azure.** Their catalogs keep the self-signed
+> `CN=punktfunk-driver` cert below, which the installer still plants in the machine `Root` store.
+> The two signatures are independent by design — Windows verifies the installer via SmartScreen/UAC
+> and driver catalogs via PnP, and never requires a common signer, which is why the installer could
+> move to a public CA without touching the driver track at all.
+>
+> Worth revisiting: these are **user-mode** (UMDF) drivers and we already clear `FORCE_INTEGRITY`, so
+> a catalog signed by the publicly trusted Azure cert would likely chain to a root every Windows box
+> already has — which would let us drop the `Root` plant entirely and keep only the `TrustedPublisher`
+> entry that suppresses the device-software prompt. That is a real reduction in what we ask of a
+> user's machine, but it is **unverified**: test it on the Windows box before believing it.
+
 Our three UMDF drivers are signed with a **stable self-signed code-signing cert**, subject
 `CN=punktfunk-driver`, supplied to `build-pf-vdisplay.ps1` / `build-gamepad-drivers.ps1` as the
 `DRIVER_CERT_PFX_B64` + `DRIVER_CERT_PASSWORD` Actions secrets. On a `v*` tag build a missing cert
@@ -241,7 +294,8 @@ the recovery. From a Linux box drive either over SSH, e.g.
 #    statically links the vendored VPL dispatcher — needs cmake + a libclang, no FFmpeg)
 cargo build --release -p punktfunk-host --features nvenc,qsv
 
-# 2. pack (self-signed unless MSIX_CERT_PFX_B64/MSIX_CERT_PASSWORD are set; -NoDriver to skip pf-vdisplay)
+# 2. pack (self-signed unless the AZURE_CODESIGNING_* trio or MSIX_CERT_PFX_B64/MSIX_CERT_PASSWORD
+#    are set — see "Installer signing" above; -NoDriver to skip pf-vdisplay)
 pwsh -File packaging\windows\pack-host-installer.ps1 -Version 0.0.0-dev -TargetDir C:\t\release -OutDir C:\t\out
 ```
 

packaging/windows/pack-host-installer.ps1

@@ -4,15 +4,24 @@
 
 .DESCRIPTION
   From a release `cargo build -p punktfunk-host --features nvenc` output (the exe), this:
-    1. resolves a code-signing cert (supplied stable .pfx from CI secrets OR an ephemeral self-signed
-       CN=unom - same scheme as the client's pack-msix.ps1) and exports the public .cer. The
-       ephemeral fallback is for canary/CI/dev ONLY: on a v* tag build a missing cert (or -NoSign)
-       is a hard failure, never a silent downgrade to a throwaway cert - see -RequireSignedCert,
+    1. resolves a signing backend - Azure Artifact Signing (formerly Trusted Signing) when the
+       AZURE_CODESIGNING_* trio is set, else a supplied stable .pfx from CI secrets, else an
+       ephemeral self-signed CN=unom - same scheme as the client's pack-msix.ps1. The .pfx paths
+       also export the public .cer; Azure does not (see below). The ephemeral fallback is for
+       canary/CI/dev ONLY: on a v* tag build a missing cert (or -NoSign) is a hard failure, never
+       a silent downgrade to a throwaway cert - see -RequireSignedCert,
     2. signs the inner punktfunk-host.exe,
     3. stages the pf-vdisplay virtual-display driver bundle (unless -NoDriver),
     4. runs ISCC to build punktfunk-host-setup-<ver>.exe,
-    5. signs the setup.exe (timestamp best-effort),
-    6. emits HOST_SETUP_PATH / HOST_CER_PATH to GITHUB_ENV for the publish step.
+    5. signs the setup.exe (timestamped - MANDATORY under Azure signing, see Sign-File),
+    6. emits HOST_SETUP_PATH / HOST_CER_PATH to GITHUB_ENV for the publish step. Azure signing
+       emits no .cer: the chain is publicly trusted, so there is nothing for a user to import.
+       Every consumer of HOST_CER_PATH already guards on Test-Path, so it is simply absent.
+
+  NOTE the drivers are signed separately, by build-pf-vdisplay.ps1 / build-gamepad-drivers.ps1 with
+  the DRIVER_CERT_* secret, and are NOT re-signed here (that would invalidate their catalogs). The
+  installer's signature and the driver catalogs' signatures are independent by design - Windows
+  verifies the first via SmartScreen/UAC and the second via PnP, and never requires a common signer.
 
   Idempotent; safe to re-run. Run on the Windows runner / dev box (MSVC + Windows SDK + Inno Setup).
 
@@ -24,9 +33,20 @@ param(
     [Parameter(Mandatory = $true)][string]$Version,                 # e.g. 0.2.137 or 1.4.0 (free-form)
     [Parameter(Mandatory = $true)][string]$TargetDir,               # cargo --release dir (has punktfunk-host.exe)
     [string]$OutDir = (Join-Path $TargetDir 'installer'),
+    # Subject for the EPHEMERAL self-signed fallback only. Azure signing carries its own subject
+    # (the profile's verified CN/O), and nothing downstream of setup.exe compares the two - unlike
+    # the MSIX, whose manifest Identity/@Publisher must match byte-for-byte. See pack-msix.ps1.
     [string]$Publisher = 'CN=unom',
     [string]$PfxBase64 = $env:MSIX_CERT_PFX_B64,                    # reuse the client's signing secret
     [string]$PfxPassword = $env:MSIX_CERT_PASSWORD,
+    # Azure Artifact Signing (formerly Trusted Signing). All three must be set to select it; it then
+    # takes precedence over any .pfx. Credentials come from the environment via DefaultAzureCredential
+    # (AZURE_TENANT_ID / AZURE_CLIENT_ID / AZURE_CLIENT_SECRET) - never passed as arguments, so they
+    # cannot leak into a process listing or a transcript.
+    [string]$AzureEndpoint = $env:AZURE_CODESIGNING_ENDPOINT,       # e.g. https://neu.codesigning.azure.net/
+    [string]$AzureAccount = $env:AZURE_CODESIGNING_ACCOUNT,         # signing account name
+    [string]$AzureProfile = $env:AZURE_CODESIGNING_PROFILE,         # certificate profile name
+    [string]$AzureDlib = $env:AZURE_CODESIGNING_DLIB,               # path to Azure.CodeSigning.Dlib.dll
     [string]$FfmpegDir = $env:FFMPEG_DIR,                           # bundle its bin\*.dll (amf-qsv build)
     [string]$WebDir = $env:WEB_OUTPUT_DIR,                          # built web .output tree -> bundle the mgmt console
     [string]$ScriptingBundle = $env:SCRIPTING_BUNDLE,              # built runner-cli.js -> bundle the plugin/script runner
@@ -70,6 +90,29 @@ function Find-SdkTool([string]$name) {
     if (-not $hit) { throw "$name not found under $root - install the Windows 10/11 SDK." }
     $hit.FullName
 }
+# Azure.CodeSigning.Dlib.dll ships in the Microsoft.Trusted.Signing.Client NuGet package, which has no
+# installer and no fixed location - hence an explicit override first, then the two paths the runner
+# setup uses (see packaging/windows/README.md). Newest version wins so a package update is picked up
+# without editing this script.
+function Find-AzureDlib([string]$Explicit) {
+    if ($Explicit) {
+        if (-not (Test-Path $Explicit)) { throw "AZURE_CODESIGNING_DLIB points at a missing file: $Explicit" }
+        return (Resolve-Path $Explicit).Path
+    }
+    $roots = @(
+        (Join-Path $env:USERPROFILE '.nuget\packages\microsoft.trusted.signing.client'),
+        'C:\trusted-signing\microsoft.trusted.signing.client'
+    ) | Where-Object { $_ -and (Test-Path $_) }
+    $hit = $roots | ForEach-Object { Get-ChildItem -Path $_ -Recurse -Filter 'Azure.CodeSigning.Dlib.dll' -ErrorAction SilentlyContinue } |
+        Where-Object { $_.FullName -match '\\bin\\x64\\' } |
+        Sort-Object LastWriteTime | Select-Object -Last 1
+    if (-not $hit) {
+        throw ("Azure.CodeSigning.Dlib.dll not found. Install the signing client on this box, e.g. " +
+               "``nuget install Microsoft.Trusted.Signing.Client -OutputDirectory " +
+               "`$env:USERPROFILE\.nuget\packages``, or set AZURE_CODESIGNING_DLIB to its full path.")
+    }
+    $hit.FullName
+}
 $iscc = Find-Iscc
 Write-Host "ISCC: $iscc"
 
@@ -87,20 +130,43 @@ if ($NoSign -and $requireCert) {
 }
 $pfxPath = Join-Path $OutDir 'signing.pfx'
 $cerPath = Join-Path $OutDir "punktfunk-host-windows_${Version}.cer"
+$azureMetadata = Join-Path $OutDir 'azure-codesigning.json'
+$signMode = 'none'
 $signtool = $null
 if (-not $NoSign) {
     $signtool = Find-SdkTool 'signtool.exe'
     Write-Host "signtool: $signtool"
-    if ($PfxBase64) {
+    if ($AzureEndpoint -and $AzureAccount -and $AzureProfile) {
+        $signMode = 'azure'
+        $AzureDlib = Find-AzureDlib $AzureDlib
+        # signtool reads the account/profile from this file (/dmdf) rather than the command line.
+        @{
+            Endpoint                = $AzureEndpoint
+            CodeSigningAccountName  = $AzureAccount
+            CertificateProfileName  = $AzureProfile
+        } | ConvertTo-Json | Set-Content -Path $azureMetadata -Encoding utf8
+        Write-Host "signing via Azure Artifact Signing: $AzureAccount/$AzureProfile at $AzureEndpoint"
+        Write-Host "  dlib: $AzureDlib"
+        foreach ($v in 'AZURE_TENANT_ID', 'AZURE_CLIENT_ID', 'AZURE_CLIENT_SECRET') {
+            if (-not [Environment]::GetEnvironmentVariable($v)) {
+                throw ("Azure signing selected but $v is not set. The dlib authenticates with " +
+                       "DefaultAzureCredential; without the service-principal trio it falls through to " +
+                       "an interactive login that cannot complete on a runner and hangs the build.")
+            }
+        }
+    }
+    elseif ($PfxBase64) {
+        $signMode = 'pfx'
         Write-Host "signing with supplied code-signing cert (MSIX_CERT_PFX_B64)"
         [IO.File]::WriteAllBytes($pfxPath, [Convert]::FromBase64String($PfxBase64))
     }
     elseif ($requireCert) {
-        throw ("release build ($env:GITHUB_REF) with no MSIX_CERT_PFX_B64 - refusing to fall back to " +
-               "an ephemeral self-signed cert. Restore the MSIX_CERT_PFX_B64 / MSIX_CERT_PASSWORD " +
-               "repo secrets, or pass -RequireSignedCert false if this really is a test build.")
+        throw ("release build ($env:GITHUB_REF) with neither AZURE_CODESIGNING_* nor MSIX_CERT_PFX_B64 - " +
+               "refusing to fall back to an ephemeral self-signed cert. Restore the signing secrets " +
+               "(packaging/windows/README.md), or pass -RequireSignedCert false if this really is a test build.")
     }
     else {
+        $signMode = 'selfsigned'
         Write-Host "no MSIX_CERT_PFX_B64 -> generating an ephemeral self-signed cert (subject $Publisher)"
         if (-not $PfxPassword) { $PfxPassword = 'punktfunk' }
         $tmp = New-SelfSignedCertificate -Type Custom -Subject $Publisher `
@@ -111,25 +177,44 @@ if (-not $NoSign) {
         Export-PfxCertificate -Cert "Cert:\CurrentUser\My\$($tmp.Thumbprint)" -FilePath $pfxPath -Password $sec | Out-Null
         Remove-Item "Cert:\CurrentUser\My\$($tmp.Thumbprint)" -Force
     }
-    # Always export the public .cer. For a self-signed cert it's the file users import once
-    # (LocalMachine\TrustedPublisher) so SmartScreen/UAC trusts the signed setup.exe; for a real CA
-    # cert it's a harmless extra.
-    $pwsec = if ($PfxPassword) { ConvertTo-SecureString -String $PfxPassword -Force -AsPlainText } else { $null }
-    $pubCert = if ($pwsec) { Get-PfxCertificate -FilePath $pfxPath -Password $pwsec } else { Get-PfxCertificate -FilePath $pfxPath }
-    Export-Certificate -Cert $pubCert -FilePath $cerPath | Out-Null
-    Write-Host "signing cert subject=$($pubCert.Subject) thumbprint=$($pubCert.Thumbprint)"
+    # Export the public .cer for the .pfx-backed modes. For a self-signed cert it's the file users
+    # import once (LocalMachine\TrustedPublisher) so SmartScreen/UAC trusts the signed setup.exe.
+    # Azure signing has no .pfx to read and needs no import - the chain is publicly trusted - so it
+    # deliberately produces no .cer and HOST_CER_PATH stays unset.
+    if ($signMode -ne 'azure') {
+        $pwsec = if ($PfxPassword) { ConvertTo-SecureString -String $PfxPassword -Force -AsPlainText } else { $null }
+        $pubCert = if ($pwsec) { Get-PfxCertificate -FilePath $pfxPath -Password $pwsec } else { Get-PfxCertificate -FilePath $pfxPath }
+        Export-Certificate -Cert $pubCert -FilePath $cerPath | Out-Null
+        Write-Host "signing cert subject=$($pubCert.Subject) thumbprint=$($pubCert.Thumbprint)"
+    }
 }
 
+# A timestamp is best-effort for a .pfx whose cert outlives the release, but MANDATORY under Azure
+# signing: those leaf certs are minted per request and expire in ~3 days, so an untimestamped
+# signature stops verifying within days of shipping. Retrying without one there would produce an
+# artifact that passes on the runner and fails on every user's machine that weekend - so the
+# fallback is gated on the mode rather than applied blindly.
 function Sign-File([string]$Path) {
     if ($NoSign) { return }
-    $signArgs = @('sign', '/fd', 'SHA256', '/f', $pfxPath)
-    if ($PfxPassword) { $signArgs += @('/p', $PfxPassword) }
-    & $signtool ($signArgs + @('/tr', 'http://timestamp.digicert.com', '/td', 'SHA256', $Path))
-    if ($LASTEXITCODE -ne 0) {
-        Write-Warning "timestamped sign failed for $Path - retrying without a timestamp"
-        & $signtool ($signArgs + @($Path))
-        if ($LASTEXITCODE -ne 0) { throw "signtool sign failed for $Path ($LASTEXITCODE)" }
+    if ($signMode -eq 'azure') {
+        $signArgs = @('sign', '/fd', 'SHA256', '/dlib', $AzureDlib, '/dmdf', $azureMetadata)
+        $ts = 'http://timestamp.acs.microsoft.com'
     }
+    else {
+        $signArgs = @('sign', '/fd', 'SHA256', '/f', $pfxPath)
+        if ($PfxPassword) { $signArgs += @('/p', $PfxPassword) }
+        $ts = 'http://timestamp.digicert.com'
+    }
+    & $signtool ($signArgs + @('/tr', $ts, '/td', 'SHA256', $Path))
+    if ($LASTEXITCODE -eq 0) { return }
+    if ($signMode -eq 'azure') {
+        throw ("timestamped sign failed for $Path ($LASTEXITCODE) - NOT retrying without a timestamp. " +
+               "An Azure signing cert is valid for ~3 days; an untimestamped signature would go " +
+               "untrusted within days of release.")
+    }
+    Write-Warning "timestamped sign failed for $Path - retrying without a timestamp"
+    & $signtool ($signArgs + @($Path))
+    if ($LASTEXITCODE -ne 0) { throw "signtool sign failed for $Path ($LASTEXITCODE)" }
 }
 
 # --- sign the inner exes before they're packed -------------------------------------------------
@@ -340,14 +425,18 @@ if (-not (Test-Path $setup)) { throw "expected installer not produced: $setup" }
 # --- sign the setup.exe + clean up ------------------------------------------------------------
 Sign-File $setup
 Remove-Item $pfxPath -Force -ErrorAction SilentlyContinue
+Remove-Item $azureMetadata -Force -ErrorAction SilentlyContinue
 
 Write-Host ""
 Write-Host "==> installer: $setup"
-if (-not $NoSign) {
+if ($signMode -eq 'azure') {
+    Write-Host "==> signed by a publicly trusted CA - nothing for users to import."
+}
+elseif (-not $NoSign) {
     Write-Host "==> trust the cert once per machine (self-signed builds), then the signed setup.exe is trusted:"
     Write-Host "    Import-Certificate -FilePath '$cerPath' -CertStoreLocation Cert:\LocalMachine\TrustedPublisher"
 }
 if ($env:GITHUB_ENV) {
     "HOST_SETUP_PATH=$setup" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8
-    if (-not $NoSign) { "HOST_CER_PATH=$cerPath" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8 }
+    if (-not $NoSign -and $signMode -ne 'azure') { "HOST_CER_PATH=$cerPath" | Out-File -FilePath $env:GITHUB_ENV -Append -Encoding utf8 }
 }

packaging/winget/README.md

@@ -107,10 +107,10 @@ These manifests stay in winget-pkgs' own format rather than a bespoke one, so su
 later is a copy, not a rewrite. Two things would need attention on that path: the signing note
 below, and `Agreements` being verified-developers-only in the community repo.
 
-> **Signing.** The installer is currently signed with a self-signed cert (`CN=unom`, subject ==
-> issuer) and ships a `.cer` users import manually. winget does not sign anything; it downloads and
-> runs the same binary, so SmartScreen behaves exactly as it does for a browser download. That is a
-> pre-existing condition rather than something winget introduces — but the community repo
-> (`microsoft/winget-pkgs`) gates on it via its `Binary-Validation-Error` /
-> `Validation-Defender-Error` checks, so a submission there needs a publicly-trusted cert (Azure
-> Trusted Signing is the cheap path). A self-hosted source has no such gate.
+> **Signing.** The installer is signed with **Azure Artifact Signing** (account `unomsigning`,
+> profile `unom-io`) — a publicly trusted CA, so there is no `.cer` for users to import. This
+> removed the blocker on submitting to the community repo (`microsoft/winget-pkgs`), whose
+> `Binary-Validation-Error` / `Validation-Defender-Error` checks require a publicly trusted cert;
+> the remaining upstream obstacle is `Agreements` being verified-developers-only. Note that a
+> trusted cert is not an instant SmartScreen bypass: reputation still accrues per publisher over
+> downloads, it just now accrues to a named identity instead of being permanently unknown.

packaging/winget/server/README.md

@@ -16,12 +16,10 @@ winget upgrade unom.PunktfunkHost
 ## Why self-hosted rather than the community repo
 
 `microsoft/winget-pkgs` gates submissions on its `Binary-Validation-Error` /
-`Validation-Defender-Error` checks, and the host installer is currently signed with a self-signed
-cert (`CN=unom`). That is a pre-existing condition — winget does not sign anything, so SmartScreen
-behaves identically whether the installer arrives by browser or by `winget` — but it does block that
-route until a publicly trusted cert is in place. A self-hosted source has no such gate, can carry
-`Agreements` (verified-developers-only upstream), and can serve channels the community repo would
-never accept.
+`Validation-Defender-Error` checks, which need a publicly trusted signing cert. That blocker is
+gone — the host installer is now signed with Azure Artifact Signing (see `packaging/windows/README.md`)
+— but a self-hosted source is still the right call: it has no such gate, can carry `Agreements`
+(verified-developers-only upstream), and can serve channels the community repo would never accept.
 
 ## What it implements
 

scripts/ci/provision-windows-punktfunk-extras.ps1

@@ -113,4 +113,60 @@ $env:PATH = "C:\Users\Public\ffmpeg\bin;" + $env:PATH
 '@ | Set-Content -Encoding UTF8 $projectEnv
 info "wrote $projectEnv (FFMPEG_DIR) - restart the gitea-act-runner scheduled task to pick it up"
 
+# --- Azure Artifact Signing (formerly Trusted Signing) toolchain, for the signing step in
+# windows-host.yml + windows-client.yml. Two pieces, neither of which the generic unom/infra image
+# carries, and both of which fail in ways that do not name themselves:
+#
+#   1. The .NET 8 runtime. Azure.CodeSigning.Dlib.dll is a mixed-mode (C++/CLI) assembly - it ships
+#      Ijwhost.dll and a runtimeconfig.json pinning Microsoft.NETCore.App 8.0.0 - so on a box with
+#      no .NET runtime, signtool exits 3 having printed NOTHING AT ALL. Verified on .133 2026-08-14:
+#      the box had pwsh 7 (self-contained, brings no shared runtime) and no dotnet whatsoever.
+#   2. The signing client, installed MACHINE-WIDE under C:\trusted-signing rather than into a user's
+#      .nuget. The act_runner daemon runs as SYSTEM, whose USERPROFILE is
+#      C:\Windows\System32\config\systemprofile - so a per-user install under Administrator is
+#      invisible to every job that actually builds. Find-AzureDlib in both pack scripts searches
+#      this exact path for that reason; verified by resolving it from a SYSTEM scheduled task.
+#
+# Both are SHA-256 pinned against version-immutable URLs (a nuget.org flat-container package and the
+# dotnet builds CDN are both immutable per version), so these fail closed on tampering rather than
+# every time Microsoft ships a patch release. Bump version + hash together to move either. ---
+$dotnetVer = '8.0.30'
+$dotnetSha = 'E40F199C6D5584AFF0554C01163C3C8D9CCF6BEC3A577E4D967E41070772A1C1'
+$tscVer = '1.0.95'
+$tscSha = '3BFCF1E0A3CB42AF1692F0A8ED45C15DE070C2DE86F28A59B2795D904D8A920F'
+
+if (Test-Path 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App') {
+  info "shared .NET runtime already present ($((Get-ChildItem 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App' | ForEach-Object Name) -join ', '))"
+} else {
+  info "installing .NET $dotnetVer runtime (required by Azure.CodeSigning.Dlib.dll)"
+  $dn = "$env:TEMP\dotnet-runtime-$dotnetVer-win-x64.exe"
+  Invoke-WebRequest -Uri "https://builds.dotnet.microsoft.com/dotnet/Runtime/$dotnetVer/dotnet-runtime-$dotnetVer-win-x64.exe" -OutFile $dn -UseBasicParsing
+  $got = (Get-FileHash $dn -Algorithm SHA256).Hash
+  if ($got -ne $dotnetSha) { Remove-Item $dn -Force; throw ".NET runtime download hash mismatch (got $got, pinned $dotnetSha)." }
+  # -Wait is load-bearing: the bundle is a GUI PE that returns immediately when invoked with &,
+  # leaving $LASTEXITCODE unset and racing any completion check against the install.
+  $p = Start-Process -FilePath $dn -ArgumentList '/install', '/quiet', '/norestart' -Wait -PassThru
+  Remove-Item $dn -Force -ErrorAction SilentlyContinue
+  if ($p.ExitCode -ne 0) { throw ".NET runtime installer exited $($p.ExitCode)." }
+  if (-not (Test-Path 'C:\Program Files\dotnet\shared\Microsoft.NETCore.App')) { throw ".NET runtime installer reported success but installed no shared runtime." }
+}
+
+$tscDir = "C:\trusted-signing\microsoft.trusted.signing.client\$tscVer"
+if (Test-Path (Join-Path $tscDir 'bin\x64\Azure.CodeSigning.Dlib.dll')) {
+  info "Trusted Signing client $tscVer already present at $tscDir"
+} else {
+  info "installing Microsoft.Trusted.Signing.Client $tscVer (machine-wide, for SYSTEM)"
+  $nupkg = "$env:TEMP\microsoft.trusted.signing.client.$tscVer.nupkg"
+  Invoke-WebRequest -Uri "https://api.nuget.org/v3-flatcontainer/microsoft.trusted.signing.client/$tscVer/microsoft.trusted.signing.client.$tscVer.nupkg" -OutFile $nupkg -UseBasicParsing
+  $got = (Get-FileHash $nupkg -Algorithm SHA256).Hash
+  if ($got -ne $tscSha) { Remove-Item $nupkg -Force; throw "Trusted Signing client download hash mismatch (got $got, pinned $tscSha)." }
+  if (Test-Path $tscDir) { Remove-Item -Recurse -Force $tscDir }
+  New-Item -ItemType Directory -Force -Path $tscDir | Out-Null
+  Add-Type -AssemblyName System.IO.Compression.FileSystem
+  [System.IO.Compression.ZipFile]::ExtractToDirectory($nupkg, $tscDir)
+  Remove-Item $nupkg -Force -ErrorAction SilentlyContinue
+  Get-ChildItem -Path $tscDir -Recurse -File | Unblock-File -ErrorAction SilentlyContinue
+  if (-not (Test-Path (Join-Path $tscDir 'bin\x64\Azure.CodeSigning.Dlib.dll'))) { throw "extracted $tscVer but bin\x64\Azure.CodeSigning.Dlib.dll is absent." }
+}
+
 info "punktfunk extras provisioned OK."