feat(linux): a desktop app for Linux, with the tray, Settings, Dumps, setup and packaging

.github/workflows/beta.yml

@@ -100,7 +100,9 @@ jobs:
       - name: Release
         run: |
           go run ./tools/release notes > "$RUNNER_TEMP/notes.md"
-          for f in "dist/Flock-$VERSION-macOS.dmg" "dist/Flock-Setup-$VERSION-x64.exe"; do
+          for f in "dist/Flock-$VERSION-macOS.dmg" "dist/Flock-Setup-$VERSION-x64.exe" \
+            "dist/flock-$VERSION-linux-x64.tar.gz" "dist/flock-$VERSION-linux-arm64.tar.gz" \
+            "dist/flock-app-$VERSION-linux-x64.tar.gz"; do
             [ -f "$f" ] || { echo "::error::$f missing"; exit 1; }
           done
           gh release create "v$VERSION" --repo "$GITHUB_REPOSITORY" --target "$SHA" --prerelease --latest=false \

.github/workflows/build.yml

@@ -1,5 +1,5 @@
-# Runs the Go tests, and builds the macOS disk image (signed and notarized) and the Windows installer
-# (signed with Artifact Signing) and keeps them as run artifacts. Signing takes the secrets and
+# Runs the Go tests, and builds the macOS disk image (signed and notarized), the Windows installer
+# (signed with Artifact Signing) and the Linux CLI archives, and keeps them as run artifacts. Signing takes the secrets and
 # variables of the "release" environment, and is required in the merge queue and for releases.
 #
 #   - on every pull request: the Go tests only; the builds are skipped (which counts as passed)
@@ -64,7 +64,7 @@ jobs:
           fi
           echo "version=$version" >> "$GITHUB_OUTPUT"
 
-  # The Go tests on both platforms Flock supports (the race detector needs cgo, so macOS only).
+  # The Go tests on the platforms Flock supports (the race detector needs cgo, so not on Windows).
   go-test:
     name: Go tests (${{ matrix.name }})
     needs: version
@@ -74,6 +74,8 @@ jobs:
         include:
           - { name: macOS, os: macos-26, flags: -race }
           - { name: Windows, os: windows-2025, flags: "" }
+          - { name: Linux, os: ubuntu-24.04, flags: -race }
+          - { name: Linux arm64, os: ubuntu-24.04-arm, flags: -race }
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v7
@@ -272,3 +274,58 @@ jobs:
           name: flock-windows
           path: windows/dist/Flock-Setup-*-x64.exe
           if-no-files-found: error
+
+  linux:
+    name: Linux (x64, arm64)
+    needs: version
+    if: github.event_name != 'pull_request'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.ref || github.event.pull_request.head.sha }}
+
+      - uses: actions/setup-go@v7
+        with:
+          go-version-file: go.mod
+
+      - name: Build archives
+        run: make linux VERSION=${{ needs.version.outputs.version }}
+
+      - uses: actions/upload-artifact@v7
+        with:
+          name: flock-linux
+          path: |
+            dist/flock-*-linux-*.tar.gz
+            dist/flock-*-linux-*.tar.gz.sha256
+          if-no-files-found: error
+
+  linux-app:
+    name: Linux app (x64)
+    needs: version
+    if: github.event_name != 'pull_request'
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v7
+        with:
+          ref: ${{ inputs.ref || github.event.pull_request.head.sha }}
+
+      - uses: actions/setup-go@v7
+        with:
+          go-version-file: linux/go.mod
+          cache-dependency-path: linux/go.sum
+
+      # cgo against GTK 3 and WebKitGTK 4.1 (Wails' gtk3 build tag).
+      - name: Install GTK and WebKitGTK
+        run: sudo apt-get update && sudo apt-get install -y --no-install-recommends libgtk-3-dev libwebkit2gtk-4.1-dev
+
+      - name: Build archive
+        run: make linux-app-archive VERSION=${{ needs.version.outputs.version }}
+
+      - uses: actions/upload-artifact@v7
+        with:
+          name: flock-linux-app
+          path: |
+            dist/flock-app-*-linux-x64.tar.gz
+            dist/flock-app-*-linux-x64.tar.gz.sha256
+          if-no-files-found: error

.github/workflows/release.yml

@@ -128,7 +128,9 @@ jobs:
           VERSION: ${{ needs.release-please.outputs.version }}
         run: |
           ls dist
-          for f in "dist/Flock-$VERSION-macOS.dmg" "dist/Flock-Setup-$VERSION-x64.exe"; do
+          for f in "dist/Flock-$VERSION-macOS.dmg" "dist/Flock-Setup-$VERSION-x64.exe" \
+            "dist/flock-$VERSION-linux-x64.tar.gz" "dist/flock-$VERSION-linux-arm64.tar.gz" \
+            "dist/flock-app-$VERSION-linux-x64.tar.gz"; do
             [ -f "$f" ] || { echo "::error::$f missing"; exit 1; }
           done
           gh release upload "$TAG" dist/* --clobber --repo "$GITHUB_REPOSITORY"

Makefile

@@ -1,14 +1,16 @@
 VERSION ?= $(shell git describe --tags --always --dirty 2>/dev/null || echo dev)
 LDFLAGS := -s -w -X flock/internal/cli.Version=$(VERSION)
 
-.PHONY: build build-all test lint notices app dmg windows windows-test
+.PHONY: build build-all test lint notices app dmg windows windows-test linux linux-app linux-app-archive
 
 build:
 	go build -ldflags "$(LDFLAGS)" -o bin/flock ./cmd/flock
 
 build-all:
 	GOOS=darwin  GOARCH=arm64 go build -ldflags "$(LDFLAGS)" -o dist/flock-darwin-arm64 ./cmd/flock
 	GOOS=windows GOARCH=amd64 go build -ldflags "$(LDFLAGS)" -o dist/flock-windows-amd64.exe ./cmd/flock
+	GOOS=linux   GOARCH=amd64 go build -ldflags "$(LDFLAGS)" -o dist/flock-linux-amd64 ./cmd/flock
+	GOOS=linux   GOARCH=arm64 go build -ldflags "$(LDFLAGS)" -o dist/flock-linux-arm64 ./cmd/flock
 
 test:
 	go test -race ./...
@@ -33,6 +35,36 @@ windows:
 	GOOS=windows GOARCH=amd64 go build -ldflags "-s -w -X main.version=$(VERSION)" -o dist/windows-amd64/flock-helper.exe ./cmd/flock-helper
 	GOOS=windows GOARCH=amd64 go build -ldflags "-s -w -H windowsgui" -o dist/windows-amd64/flockd.exe ./cmd/flockd
 
+# The Linux CLI as release archives (install.sh and the AUR package download these):
+# dist/flock-<version>-linux-{x64,arm64}.tar.gz with flock-php (util-linux owns flock), each with its .sha256.
+linux:
+	for a in x64:amd64 arm64:arm64; do \
+		name=flock-$(VERSION)-linux-$${a%%:*}; \
+		rm -rf dist/$$name && mkdir -p dist/$$name && \
+		CGO_ENABLED=0 GOOS=linux GOARCH=$${a##*:} go build -trimpath -ldflags "$(LDFLAGS)" -o dist/$$name/flock-php ./cmd/flock && \
+		cp LICENSE NOTICE THIRD_PARTY_NOTICES dist/$$name/ && \
+		tar -C dist/$$name -czf dist/$$name.tar.gz flock-php LICENSE NOTICE THIRD_PARTY_NOTICES && \
+		rm -r dist/$$name && \
+		(cd dist && sha256sum $$name.tar.gz > $$name.tar.gz.sha256) || exit 1; \
+	done
+
+# The Linux tray app, bin/flock-app (linux/, a module of its own). Needs cgo, GTK 3 and WebKitGTK:
+# Arch webkit2gtk-4.1, Ubuntu libwebkit2gtk-4.1-dev, Fedora webkit2gtk4.1-devel.
+linux-app:
+	cd linux && go build -tags gtk3 -trimpath -ldflags "-s -w" -o ../bin/flock-app ./app
+
+# The Linux app as a release archive (the AUR package flock-php-app downloads it), x64 only: it needs
+# cgo against GTK and WebKitGTK, so arm64 would need an arm64 runner.
+# dist/flock-app-<version>-linux-x64.tar.gz with flock-app, its .desktop entry and icon, and its .sha256.
+linux-app-archive: linux-app
+	name=flock-app-$(VERSION)-linux-x64; \
+	rm -rf dist/$$name && mkdir -p dist/$$name && \
+	cp bin/flock-app linux/flock-app.desktop LICENSE NOTICE THIRD_PARTY_NOTICES dist/$$name/ && \
+	cp linux/app/icons/AppIcon.png dist/$$name/flock-app.png && \
+	tar -C dist/$$name -czf dist/$$name.tar.gz flock-app flock-app.desktop flock-app.png LICENSE NOTICE THIRD_PARTY_NOTICES && \
+	rm -r dist/$$name && \
+	cd dist && sha256sum $$name.tar.gz > $$name.tar.gz.sha256
+
 # The tray app's models and API client (windows/FlockKit) run on any OS; the app itself is built on Windows (windows/build.ps1).
 windows-test:
 	dotnet test windows/FlockKit.Tests