Merge pull request #3554 from vitorpamplona/claude/flatpak-desktop-release-ci-wfbcre

Add Flatpak bundle support to release CI + Flathub submission
2026-08-10 16:33:27 +00:00 · 2026-07-14 10:48:19 -04:00
parent d043f4d143 079417ba60
commit 4fcae15bcb
12 changed files with 324 additions and 42 deletions
@@ -44,7 +44,7 @@ jobs:
          - { os: ubuntu-latest,  arch: x64,   family: linux,          tasks: "packageReleaseDeb packageReleaseRpm" }
          - { os: ubuntu-latest,  arch: x64,   family: linux-portable, tasks: "createReleaseAppImage createReleaseDistributable" }
    runs-on: ${{ matrix.os }}
-    timeout-minutes: 45
+    timeout-minutes: 60  # linux-portable leg also downloads the freedesktop runtime + builds the Flatpak bundle
    defaults:
      run:
        shell: bash
@@ -101,6 +101,25 @@ jobs:
          fi
          chmod +x desktopApp/packaging/appimage/appimagetool-x86_64.AppImage

+      # Flatpak tooling + the freedesktop runtime/sdk the manifest pins
+      # (runtime-version is greped from the manifest so this never drifts).
+      # Retried: the runtime download from Flathub is ~1 GB and flatpak
+      # install resumes cleanly on re-run.
+      - name: Install Flatpak tooling + runtimes (linux-portable only)
+        if: matrix.family == 'linux-portable'
+        uses: nick-fields/retry@ad984534de44a9489a53aefd81eb77f87c70dc60  # v4.0.0
+        with:
+          max_attempts: 3
+          timeout_minutes: 15
+          command: |
+            set -euo pipefail
+            sudo apt-get update && sudo apt-get install -y flatpak flatpak-builder
+            flatpak remote-add --user --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
+            FDO_VER=$(grep -E "^runtime-version:" desktopApp/packaging/flatpak/com.vitorpamplona.amethyst.Desktop.yml | cut -d"'" -f2)
+            flatpak install --user --noninteractive flathub \
+              "org.freedesktop.Platform//${FDO_VER}" \
+              "org.freedesktop.Sdk//${FDO_VER}"
+
      # macOS only: import the Developer ID Application cert into a throwaway
      # keychain so jpackage's codesign pass can find it. Soft — if the
      # MAC_CERTIFICATE_P12 secret isn't set (forks, or before Apple creds are
@@ -161,6 +180,36 @@ jobs:
            ( cd "$APP" && tar czf "../../../../portable/amethyst-desktop-${VER}-linux-x64.tar.gz" Amethyst/ )
          fi

+      # Flatpak bundle: wraps the same createReleaseDistributable tree the
+      # AppImage uses. The manifest (desktopApp/packaging/flatpak/) copies the
+      # prebuilt jpackage tree into /app — no Gradle runs inside the sandbox.
+      # build-bundle emits a single-file .flatpak whose baked-in runtime-repo
+      # lets the user's flatpak fetch the freedesktop runtime from Flathub on
+      # install. --disable-rofiles-fuse: GH runners lack a usable rofiles-fuse.
+      - name: Build Flatpak bundle (linux-portable only)
+        if: matrix.family == 'linux-portable'
+        run: |
+          set -euo pipefail
+          VER="${{ steps.ver.outputs.version }}"
+          PKG="desktopApp/packaging/flatpak"
+          APP_ID="com.vitorpamplona.amethyst.Desktop"
+          OUT="desktopApp/build/flatpak"
+          # Inject the AppStream <release> entry for this build (the checked-in
+          # metainfo deliberately carries none — CI is the source of truth).
+          sed -i "s|<releases>|<releases>\n    <release version=\"${VER}\" date=\"$(date -u +%F)\" />|" \
+            "${PKG}/${APP_ID}.metainfo.xml"
+          mkdir -p "$OUT"
+          flatpak-builder --user --force-clean --disable-rofiles-fuse \
+            --state-dir="${OUT}/.flatpak-builder" \
+            --repo="${OUT}/repo" \
+            "${OUT}/build-dir" \
+            "${PKG}/${APP_ID}.yml"
+          flatpak build-bundle "${OUT}/repo" \
+            "${OUT}/Amethyst-${VER}-x86_64.flatpak" \
+            "$APP_ID" \
+            --runtime-repo=https://dl.flathub.org/repo/flathub.flatpakrepo
+          ls -la "$OUT"
+
      - name: Collect + rename assets
        run: |
          set -euo pipefail
@@ -180,6 +180,11 @@ desktopApp/src/jvmMain/appResources/*/ffmpeg/*
 desktopApp/packaging/appimage/appimagetool-x86_64.AppImage
 desktopApp/packaging/appimage/squashfs-root/

+# flatpak-builder state/cache from local builds (CI uses --state-dir under desktopApp/build/)
+.flatpak-builder/
+desktopApp/packaging/flatpak/**/build-dir/
+desktopApp/packaging/flatpak/**/repo/
+
 # Git worktrees
 .worktrees/
 .claude/worktrees/
@@ -37,7 +37,9 @@ Platform-specific:
 - **macOS**: Xcode Command Line Tools (`xcode-select --install`)
 - **Windows**: WiX Toolset 3.x on PATH (for MSI). `winget install WiXToolset.WiXToolset`
 - **Linux (all)**: nothing extra for `.deb`; `rpm` + `fakeroot` for `.rpm`;
-  `appimagetool` + `desktop-file-utils` for AppImage
+  `appimagetool` + `desktop-file-utils` for AppImage; `flatpak` +
+  `flatpak-builder` for the Flatpak bundle (see
+  [`desktopApp/packaging/flatpak/README.md`](desktopApp/packaging/flatpak/README.md))

 Install Linux RPM tooling:

@@ -109,6 +111,7 @@ are **not** required to build Amethyst from the committed sources.
 | Linux `.deb` | `./gradlew :desktopApp:packageReleaseDeb` | `desktopApp/build/compose/binaries/main-release/deb/amethyst_*.deb` |
 | Linux `.rpm` | `./gradlew :desktopApp:packageReleaseRpm` | `desktopApp/build/compose/binaries/main-release/rpm/amethyst-*.rpm` |
 | Linux AppImage | `./gradlew :desktopApp:createReleaseAppImage` | `desktopApp/build/appimage/Amethyst-*-x86_64.AppImage` |
+| Linux Flatpak | `flatpak-builder` over `createReleaseDistributable` output — see [`desktopApp/packaging/flatpak/README.md`](desktopApp/packaging/flatpak/README.md) | `desktopApp/build/flatpak/Amethyst-*-x86_64.flatpak` (CI) |
 | Windows `.zip` portable | See below (inline `7z`) | — |
 | Linux `.tar.gz` portable | See below (inline `tar`) | — |

@@ -148,7 +151,7 @@ Where:
 | `<version>` | Tag stripped of leading `vX.YY.ZZ`                    |
 | `<family>` | `macos`, `windows`, `linux`                           |
 | `<arch>` | `x64`, `arm64`                                        |
-| `<ext>` | `dmg`, `msi`, `zip`, `deb`, `rpm`, `AppImage`, `tar.gz` |
+| `<ext>` | `dmg`, `msi`, `zip`, `deb`, `rpm`, `AppImage`, `flatpak`, `tar.gz` |

 Single source of truth: [`scripts/asset-name.sh`](scripts/asset-name.sh).
 Package manager manifests (Homebrew cask, Winget) depend on this exact scheme —
@@ -160,6 +163,7 @@ Examples:
 - `amethyst-desktop-1.12.1-macos-arm64.dmg`
 - `amethyst-desktop-1.12.1-windows-x64.msi`
 - `amethyst-desktop-1.12.1-linux-x64.AppImage`
+- `amethyst-desktop-1.12.1-linux-x64.flatpak`

 ---

@@ -625,12 +629,18 @@ State is shared across install channels (DMG, Homebrew, MSI, Winget, .deb,
 expose downgrade migration risks — **prefer a single install channel per
 machine**.

+**Exception: Flatpak.** The sandbox redirects XDG dirs into
+`~/.var/app/com.vitorpamplona.amethyst.Desktop/`, so a Flatpak install keeps
+its own separate state and does not see (or risk downgrading) state written
+by any other channel.
+
 | OS | App location | State directories |
 |---|---|---|
 | macOS | `/Applications/Amethyst.app` | `~/Library/Application Support/Amethyst`<br>`~/Library/Preferences/com.vitorpamplona.amethyst.desktop.plist`<br>`~/Library/Caches/Amethyst` |
 | Windows | `%LOCALAPPDATA%\Amethyst` or `C:\Program Files\Amethyst` | `%APPDATA%\Amethyst`<br>`%LOCALAPPDATA%\Amethyst` |
 | Linux (deb/rpm) | `/opt/amethyst` | `~/.config/amethyst`<br>`~/.local/share/amethyst`<br>`~/.cache/amethyst` |
 | Linux (AppImage/tar.gz) | user-chosen | Same as above |
+| Linux (Flatpak) | `/var/lib/flatpak` or `~/.local/share/flatpak` | `~/.var/app/com.vitorpamplona.amethyst.Desktop/` |

 Uninstall:

@@ -639,6 +649,8 @@ Uninstall:
 - .deb: `sudo apt remove amethyst`
 - .rpm: `sudo dnf remove amethyst`
 - AppImage / tar.gz: delete the file / extracted directory
+- Flatpak: `flatpak uninstall com.vitorpamplona.amethyst.Desktop` (add
+  `--delete-data` to also remove `~/.var/app/…`)
 - macOS `.dmg`: drag from `/Applications` to Trash, then delete state dirs manually

 ---
@@ -1,44 +1,71 @@
-# Flathub packaging for Amethyst Desktop
+# Flatpak packaging for Amethyst Desktop

-This directory contains the Flatpak manifest and associated metadata for
-publishing Amethyst Desktop on Flathub.
+This directory contains the Flatpak manifest and associated metadata. It is
+used two ways:
+
+1. **Release CI** (`.github/workflows/create-release.yml`, `linux-portable`
+   leg) builds a single-file bundle from it on every tag and attaches it to
+   the GitHub Release as `amethyst-desktop-<version>-linux-x64.flatpak`.
+2. **Flathub submission** — the `flathub/` subdirectory holds a
+   submission-ready variant that builds from the published GitHub Release
+   tarball (Flathub's build servers must fetch sources themselves; the
+   local `type: dir` tree used by CI is not allowed there).

 ## Files

- `com.vitorpamplona.amethyst.Desktop.yml` — Flatpak manifest
- `com.vitorpamplona.amethyst.Desktop.metainfo.xml` — AppStream metadata
-  (categories, license, screenshots — needs screenshots added before
-  submission)
+- `com.vitorpamplona.amethyst.Desktop.yml` — Flatpak manifest. It packages
+  the **prebuilt** jpackage tree from
+  `./gradlew :desktopApp:createReleaseDistributable` (which bundles its own
+  trimmed JRE — that's why there is no openjdk module/sdk-extension).
+- `com.vitorpamplona.amethyst.Desktop.metainfo.xml` — AppStream metadata.
+  Release CI injects the `<release>` entry for the version being built
+  (the checked-in file deliberately carries none); screenshots still need
+  to be added before any Flathub submission.
 - `com.vitorpamplona.amethyst.Desktop.desktop` — XDG desktop entry
- `icons/256/com.vitorpamplona.amethyst.Desktop.png` — TODO: copy a 256x256
-  PNG icon from `desktopApp/src/jvmMain/resources/icon.png` before
-  submission
-
-## Build prerequisites
-
- `./gradlew :desktopApp:createReleaseDistributable` — produces
-  `desktopApp/build/compose/binaries/main-release/app/Amethyst/`
- `flatpak install org.freedesktop.Platform//24.08 org.freedesktop.Sdk//24.08 org.freedesktop.Sdk.Extension.openjdk21//24.08`
+- `icons/512/com.vitorpamplona.amethyst.Desktop.png` — 512x512 icon (copy of
+  `desktopApp/src/jvmMain/resources/icon.png`)
+- `flathub/` — self-contained, copy-ready Flathub submission dir: its own
+  manifest (archive source pinned to the release tarball URL + sha256, with
+  `x-checker-data` so Flathub's update bot bumps it), its own metainfo
+  (carries the permanent `<releases>` history Flathub requires), desktop
+  entry, icon, and `flathub.json` (`only-arches: x86_64` — we publish no
+  aarch64 tarball, and jpackage can't cross-compile one)

 ## Local build

 ```bash
+# 1. Build the app tree the manifest packages
+./gradlew :desktopApp:createReleaseDistributable
+
+# 2. Tooling + Flathub remote (one-time)
+sudo apt-get install -y flatpak flatpak-builder   # or distro equivalent
+flatpak remote-add --user --if-not-exists flathub https://dl.flathub.org/repo/flathub.flatpakrepo
+
+# 3. Build + install locally
 cd desktopApp/packaging/flatpak
-flatpak-builder --user --install --force-clean build-dir com.vitorpamplona.amethyst.Desktop.yml
+flatpak-builder --user --install --install-deps-from=flathub --force-clean \
+  build-dir com.vitorpamplona.amethyst.Desktop.yml
 flatpak run com.vitorpamplona.amethyst.Desktop
 ```

-## Submission to Flathub
+To produce the distributable single-file bundle instead (what CI ships):

-Follow https://docs.flathub.org/docs/for-app-authors/submission
+```bash
+flatpak-builder --user --install-deps-from=flathub --force-clean \
+  --repo=repo build-dir com.vitorpamplona.amethyst.Desktop.yml
+flatpak build-bundle repo amethyst.flatpak com.vitorpamplona.amethyst.Desktop \
+  --runtime-repo=https://dl.flathub.org/repo/flathub.flatpakrepo
+```

-1. Fork `flathub/flathub` on GitHub.
-2. Branch from `new-pr` (NOT `master`).
-3. Copy this manifest + AppStream + desktop into a new directory matching
-   the app id.
-4. Open a PR titled "Add com.vitorpamplona.amethyst.Desktop".
-5. After merge, a per-app repo is created with write access for ongoing
-   updates.
+Installing the bundle: `flatpak install --user ./amethyst.flatpak`. The
+`--runtime-repo` baked in above lets flatpak fetch the freedesktop runtime
+from Flathub automatically on the user's machine.
+
+## Sandbox notes
+
+- `--socket=x11` (not wayland/fallback-x11): Compose Desktop renders through
+  AWT/skiko, which is X11-only on Linux and runs under XWayland on Wayland
+  sessions.

 ## Codec coverage

@@ -47,6 +74,31 @@ Follow https://docs.flathub.org/docs/for-app-authors/submission
 - HLS, H.264, AAC, MP3, Opus: covered by the GStreamer plugin set in
  `org.freedesktop.Platform 24.08` itself.

+## Submission to Flathub
+
+Follow https://docs.flathub.org/docs/for-app-authors/submission — no
+separate Flathub account exists; everything runs through GitHub PRs.
+
+**Remaining blocker before submitting:** at least one screenshot with a
+publicly reachable URL in `flathub/….metainfo.xml` (the Flathub linter
+rejects the current empty placeholder).
+
+1. Fork `flathub/flathub` on GitHub.
+2. Branch from `new-pr` (NOT `master`).
+3. Copy the contents of `flathub/` verbatim into a new top-level directory
+   named `com.vitorpamplona.amethyst.Desktop`.
+4. Open a PR titled "Add com.vitorpamplona.amethyst.Desktop".
+5. After merge, Flathub creates a per-app repo
+   (`flathub/com.vitorpamplona.amethyst.Desktop`) with write access for
+   ongoing updates. Its `x-checker-data` makes
+   flatpak-external-data-checker open update PRs there automatically on
+   each new GitHub Release (bumping url/sha256 and appending the metainfo
+   `<release>` entry).
+
+To test the Flathub variant locally, run the same flatpak-builder commands
+as above from inside `flathub/` — it downloads the pinned release tarball
+instead of using a local Gradle build.
+
 ## License metadata

 The manifest declares the binary as
@@ -8,8 +8,6 @@ app-id: com.vitorpamplona.amethyst.Desktop
 runtime: org.freedesktop.Platform
 runtime-version: '24.08'
 sdk: org.freedesktop.Sdk
-sdk-extensions:
-  - org.freedesktop.Sdk.Extension.openjdk21
 command: amethyst-desktop

 add-extensions:
@@ -26,8 +24,11 @@ cleanup-commands:
 finish-args:
  - --share=network
  - --share=ipc
-  - --socket=fallback-x11
-  - --socket=wayland
+  # Compose Desktop renders through AWT/skiko, which is X11-only on Linux
+  # (runs under XWayland on Wayland sessions). fallback-x11 + wayland would
+  # leave the app without a usable display socket on Wayland sessions, so
+  # grant x11 unconditionally.
+  - --socket=x11
  - --socket=pulseaudio
  - --device=dri
  - --filesystem=xdg-download
@@ -37,12 +38,10 @@ finish-args:
  # GStreamer plugin/cache paths (org.freedesktop.Platform exposes them by default).
  - --env=GST_PLUGIN_SYSTEM_PATH=/usr/lib/x86_64-linux-gnu/gstreamer-1.0

+# No openjdk module / sdk-extension: the jpackage tree copied below already
+# bundles its own trimmed JRE under Amethyst/lib/runtime/, so installing a
+# second JRE at /app/jre would only bloat the bundle.
 modules:
-  - name: openjdk
-    buildsystem: simple
-    build-commands:
-      - /usr/lib/sdk/openjdk21/install.sh
-
  - name: amethyst-desktop
    buildsystem: simple
    build-commands:
@@ -53,7 +52,7 @@ modules:
      - install -Dm755 amethyst-desktop.sh /app/bin/amethyst-desktop
      - install -Dm644 com.vitorpamplona.amethyst.Desktop.metainfo.xml -t /app/share/metainfo/
      - install -Dm644 com.vitorpamplona.amethyst.Desktop.desktop -t /app/share/applications/
-      - install -Dm644 icons/256/com.vitorpamplona.amethyst.Desktop.png -t /app/share/icons/hicolor/256x256/apps/
+      - install -Dm644 icons/512/com.vitorpamplona.amethyst.Desktop.png -t /app/share/icons/hicolor/512x512/apps/
    sources:
      # Built artifact from `./gradlew :desktopApp:createReleaseDistributable`.
      # Path matches Compose Multiplatform 1.11's output layout.
@@ -73,5 +72,6 @@ modules:
      - type: file
        path: com.vitorpamplona.amethyst.Desktop.desktop

-      - type: file
-        path: icons/256/com.vitorpamplona.amethyst.Desktop.png
+      - type: dir
+        path: icons
+        dest: icons
@@ -0,0 +1,9 @@
+[Desktop Entry]
+Type=Application
+Name=Amethyst Desktop
+Comment=Nostr client for desktop
+Categories=Network;InstantMessaging;
+Exec=amethyst-desktop
+Icon=com.vitorpamplona.amethyst.Desktop
+Terminal=false
+StartupWMClass=Amethyst
@@ -0,0 +1,52 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<component type="desktop-application">
+  <id>com.vitorpamplona.amethyst.Desktop</id>
+  <metadata_license>CC0-1.0</metadata_license>
+  <project_license>MIT AND LGPL-2.1-or-later AND BSD-2-Clause AND Apache-2.0</project_license>
+  <name>Amethyst Desktop</name>
+  <summary>Nostr client for desktop</summary>
+
+  <description>
+    <p>
+      Amethyst Desktop is a desktop client for the Nostr protocol.
+      Browse feeds, post notes, send zaps (Lightning Network), and
+      participate in NIP-53 live audio rooms.
+    </p>
+  </description>
+
+  <launchable type="desktop-id">com.vitorpamplona.amethyst.Desktop.desktop</launchable>
+
+  <url type="homepage">https://github.com/vitorpamplona/amethyst</url>
+  <url type="bugtracker">https://github.com/vitorpamplona/amethyst/issues</url>
+  <url type="vcs-browser">https://github.com/vitorpamplona/amethyst</url>
+
+  <developer id="com.vitorpamplona">
+    <name>Vitor Pamplona</name>
+  </developer>
+
+  <content_rating type="oars-1.1" />
+
+  <categories>
+    <category>Network</category>
+    <category>InstantMessaging</category>
+  </categories>
+
+  <screenshots>
+    <!-- BLOCKER for Flathub submission: at least one screenshot with a
+         publicly reachable <image> URL is required by the Flathub linter.
+         Suggested 1280x800 PNG, e.g.:
+    <screenshot type="default">
+      <image>https://raw.githubusercontent.com/vitorpamplona/amethyst/main/docs/screenshots/desktop-home.png</image>
+      <caption>Home feed</caption>
+    </screenshot>
+    -->
+  </screenshots>
+
+  <!-- Unlike the CI metainfo (release entry injected at build time), Flathub
+       requires the release history to live in-repo. New entries are appended
+       automatically by flatpak-external-data-checker (is-main-source: true
+       on the archive source in the manifest). -->
+  <releases>
+    <release version="1.12.6" date="2026-06-19" />
+  </releases>
+</component>
@@ -0,0 +1,98 @@
+# Flathub submission manifest for Amethyst Desktop.
+#
+# Unlike ../com.vitorpamplona.amethyst.Desktop.yml (which packages the locally
+# built tree for release CI), this variant builds from the published GitHub
+# Release tarball — Flathub's build servers must be able to fetch every source
+# themselves. This directory is copy-ready: everything in it (manifest,
+# metainfo, desktop entry, icon, flathub.json) is exactly what gets committed
+# to the flathub per-app repo at submission time.
+#
+# Update flow after each Amethyst release: bump url + sha256 on the archive
+# source and append a <release> entry to the metainfo. The x-checker-data
+# block below lets Flathub's flatpak-external-data-checker bot do both
+# automatically once the app is published.
+
+app-id: com.vitorpamplona.amethyst.Desktop
+runtime: org.freedesktop.Platform
+runtime-version: '24.08'
+sdk: org.freedesktop.Sdk
+command: amethyst-desktop
+
+add-extensions:
+  org.freedesktop.Platform.ffmpeg-full:
+    directory: lib/ffmpeg
+    version: '24.08'
+    add-ld-path: .
+    autodownload: true
+    autodelete: false
+
+cleanup-commands:
+  - mkdir -p /app/lib/ffmpeg
+
+finish-args:
+  - --share=network
+  - --share=ipc
+  # Compose Desktop renders through AWT/skiko, which is X11-only on Linux
+  # (runs under XWayland on Wayland sessions). fallback-x11 + wayland would
+  # leave the app without a usable display socket on Wayland sessions, so
+  # grant x11 unconditionally.
+  - --socket=x11
+  - --socket=pulseaudio
+  - --device=dri
+  - --filesystem=xdg-download
+  - --filesystem=xdg-pictures
+  - --talk-name=org.freedesktop.Notifications
+  - --talk-name=org.freedesktop.secrets
+  # GStreamer plugin/cache paths (org.freedesktop.Platform exposes them by default).
+  - --env=GST_PLUGIN_SYSTEM_PATH=/usr/lib/x86_64-linux-gnu/gstreamer-1.0
+
+# No openjdk module / sdk-extension: the jpackage tree in the release tarball
+# already bundles its own trimmed JRE under Amethyst/lib/runtime/.
+modules:
+  - name: amethyst-desktop
+    buildsystem: simple
+    build-commands:
+      # Drop the jpackage-emitted self-contained tree into /app/lib/Amethyst.
+      # Wrapper at /app/bin/amethyst-desktop forwards args.
+      - mkdir -p /app/lib/Amethyst
+      - cp -r ./Amethyst/* /app/lib/Amethyst/
+      - install -Dm755 amethyst-desktop.sh /app/bin/amethyst-desktop
+      - install -Dm644 com.vitorpamplona.amethyst.Desktop.metainfo.xml -t /app/share/metainfo/
+      - install -Dm644 com.vitorpamplona.amethyst.Desktop.desktop -t /app/share/applications/
+      - install -Dm644 icons/512/com.vitorpamplona.amethyst.Desktop.png -t /app/share/icons/hicolor/512x512/apps/
+    sources:
+      # jpackage self-contained tree published by release CI. The tarball
+      # carries a single Amethyst/ top-level dir — keep it (strip-components
+      # defaults to 1, which would flatten it away).
+      - type: archive
+        url: https://github.com/vitorpamplona/amethyst/releases/download/v1.12.6/amethyst-desktop-1.12.6-linux-x64.tar.gz
+        sha256: 42250027857b37f184ebca52bf6124ff6524be4bc15fedf819e4acaca8bc9538
+        strip-components: 0
+        # flatpak-external-data-checker: watches GitHub Releases and opens
+        # update PRs against the flathub repo (bumps url/sha256 above and,
+        # via is-main-source, appends the <release> entry to the metainfo).
+        x-checker-data:
+          type: json
+          is-main-source: true
+          url: https://api.github.com/repos/vitorpamplona/amethyst/releases/latest
+          version-query: .tag_name | sub("^v"; "")
+          timestamp-query: .published_at
+          url-query: '"https://github.com/vitorpamplona/amethyst/releases/download/"
+            + .tag_name + "/amethyst-desktop-" + (.tag_name | sub("^v"; ""))
+            + "-linux-x64.tar.gz"'
+
+      - type: script
+        dest-filename: amethyst-desktop.sh
+        commands:
+          - "#!/bin/sh"
+          - exec /app/lib/Amethyst/bin/Amethyst "$@"
+
+      - type: file
+        path: com.vitorpamplona.amethyst.Desktop.metainfo.xml
+
+      - type: file
+        path: com.vitorpamplona.amethyst.Desktop.desktop
+
+      - type: dir
+        path: icons
+        dest: icons
@@ -0,0 +1,3 @@
+{
+    "only-arches": ["x86_64"]
+}
@@ -8,7 +8,7 @@
 #   <version> = tag stripped of leading 'v' (e.g. "1.08.0")
 #   <family>  = macos | windows | linux
 #   <arch>    = x64 | arm64
-#   <ext>     = dmg | msi | zip | deb | rpm | AppImage | tar.gz
+#   <ext>     = dmg | msi | zip | deb | rpm | AppImage | flatpak | tar.gz
 #
 # Consumed by: .github/workflows/create-release.yml, .github/workflows/bump-*.yml,
 #              BUILDING.md, local release runbooks.
@@ -26,6 +26,7 @@
 #   amethyst-desktop-1.08.0-linux-x64.deb
 #   amethyst-desktop-1.08.0-linux-x64.rpm
 #   amethyst-desktop-1.08.0-linux-x64.AppImage
+#   amethyst-desktop-1.08.0-linux-x64.flatpak
 #   amethyst-desktop-1.08.0-linux-x64.tar.gz
 #   amy-1.08.0-macos-arm64.tar.gz
 #   amy-1.08.0-macos-x64.tar.gz
@@ -74,6 +75,7 @@ collect_assets() {
        desktopApp/build/compose/binaries/main-release/deb/*.deb \
        desktopApp/build/compose/binaries/main-release/rpm/*.rpm \
        desktopApp/build/appimage/*.AppImage \
+        desktopApp/build/flatpak/*.flatpak \
        desktopApp/build/portable/*.tar.gz \
        desktopApp/build/portable/*.zip \
    ; do