Full disclosure: I'm not a Swift dev, I mostly vibe-coded this

Lightweight macOS menu bar app that shows which apps are active on which macOS space. Relies on yabai as its backend.

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Colors, including empty
Colors, excluding empty
Mono, including empty
Mono, excluding empty

• macOS 26.2 (Tahoe) or later
• Apple Silicon (arm64)
• yabai installed and running

brew tap alber70g/tap
brew install --cask spacesbar
# the app is unsigned so remove the quarantine attribute
xattr -dr com.apple.quarantine /Applications/SpacesBar.app

1. Download the latest SpacesBar-<version>-arm64.zip from Releases.

2. Unzip and move SpacesBar.app to /Applications.

3. Because the build is unsigned, macOS Gatekeeper will block it on first launch. Remove the quarantine attribute:

   • run this shell command

     xattr -dr com.apple.quarantine /Applications/SpacesBar.app

4. Open the app. It will appear in the menu bar with no Dock icon.

Every push to master republishes a rolling dev prerelease with an unsigned .app zip built by GitHub Actions. Versioned releases are cut from v* tags.

On first launch SpacesBar writes defaults to ~/.config/spacesbar.json:

{
  "hideEmptySpaces": false,
  "iconStyle": "colored",
  "refreshFallbackSeconds": 5
}

• iconStyle: colored · monochrome
• hideEmptySpaces: hide spaces with no apps
• refreshFallbackSeconds: safety-net poll interval (event-driven refresh is primary)

The same options are available from the menu bar dropdown: icon style, hide empty spaces, copy current output, quit.

Logs: ~/Library/Logs/SpacesBar/spacesbar.log

SpacesBar listens for file-system events on ~/Library/Application Support/SpacesBar/refresh.signal. Wire yabai to touch that file so the menu bar updates instantly instead of waiting for the fallback timer.

Add to ~/.config/yabai/yabairc:

#!/usr/bin/env sh
SIGNAL="$HOME/Library/Application Support/SpacesBar/refresh.signal"
yabai -m signal --add event=space_changed       action="touch \"$SIGNAL\""
yabai -m signal --add event=window_created      action="touch \"$SIGNAL\""
yabai -m signal --add event=window_destroyed    action="touch \"$SIGNAL\""
yabai -m signal --add event=window_moved        action="touch \"$SIGNAL\""
yabai -m signal --add event=application_visible action="touch \"$SIGNAL\""
yabai -m signal --add event=application_hidden  action="touch \"$SIGNAL\""

Reload yabai (brew services restart yabai) and the menu bar will refresh on every yabai event.

Requires Xcode 26.4+ (matches MACOSX_DEPLOYMENT_TARGET = 26.2).

# Open in Xcode
open SpacesBar.xcodeproj

# Or build from CLI
xcodebuild \
  -project SpacesBar.xcodeproj \
  -scheme SpacesBar \
  -configuration Release \
  -derivedDataPath build \
  CODE_SIGN_IDENTITY="-" \
  CODE_SIGNING_REQUIRED=NO \
  CODE_SIGNING_ALLOWED=NO \
  build

open build/Build/Products/Release/SpacesBar.app

1. Bump MARKETING_VERSION in SpacesBar.xcodeproj/project.pbxproj (or let CI override it via the tag).

2. Tag and push:

   git tag v1.2.3
   git push origin v1.2.3

3. The release workflow builds SpacesBar-<version>-arm64.zip, attaches it to a GitHub Release, and — if TAP_GITHUB_TOKEN is configured — opens a bump/spacesbar-<version> pull request against alber70g/homebrew-tap updating Casks/spacesbar.rb. Merge the PR to publish the new version on the tap.

To set up the Homebrew tap the first time:

# In a separate repo named `homebrew-tap` under your GitHub account
mkdir -p Casks
cp /path/to/SpacesBar/Casks/spacesbar.rb Casks/spacesbar.rb
git add Casks/spacesbar.rb && git commit -m "Add spacesbar cask" && git push

Then create a fine-grained PAT scoped to alber70g/homebrew-tap with permissions Contents: Read and write and Pull requests: Read and write, and add it to this repo's Actions secrets as TAP_GITHUB_TOKEN. If the secret is missing the release still publishes — only the tap PR is skipped.

MIT