Scrubble

A Last.fm scrobbler for macOS and jailbroken iOS. Watches Apple's private MediaRemote framework, so any app that registers with the Now Playing system (Apple Music, VLC, foobar2000, the iOS Music app, …) gets scrobbled automatically.

Warning

On recent macOS versions, Apple has locked down MediaRemote behind some entitlements. As my device is on macOS Sequoia, Scrubble remain untested on these version.

Features

• OAuth (browser) or username + password auth, token stored in the Keychain
• Configurable scrobble threshold (default 70 % of duration, 30 s minimum)
• Per-app allowlist (macOS: hardcoded list; iOS: any app via AltList)
• Metadata cleanup — strips "Remastered", "(Live)", "feat. X", reissue tags
• macOS menu bar UI; failed scrobbles surface as a notification with Retry / Copy reason actions

Requirements

Xcode command-line tools + Theos (with patched MediaRemote.h in ${THEOS}/vendor/include). A Last.fm API key + secret from https://www.last.fm/api/account/create.

Build

macOS

make -f Makefile.macos              # → build/macos/Scrubble.app
make -f Makefile.macos run          # build and launch

iOS

make package                        # → packages/fr.rootfs.scrubble_<ver>_iphoneos-arm.deb

Install the .deb via your jailbreak's package manager. The daemon installs to /usr/local/libexec/Scrubble and runs as mobile under launchd. Rootless-aware.

Codesigning (macOS)

The default Makefile.macos ad-hoc-signs with --sign -. That works but means macOS will prompt for Keychain access on every rebuild — the signing identity changes each time and Scrubble's keychain items don't recognise the new binary.

Apple Development cert + team-prefixed entitlement

The com.apple.security.keychain-access-groups entitlement only authorises keychain access without prompts if it's prefixed with your Team ID, and only if the binary is signed by a cert whose Team ID matches that prefix.

The committed entitlements.macos.plist deliberately ships without a team prefix so it doesn't bake one developer's identity into the repo:

<key>com.apple.security.keychain-access-groups</key>
<array>
    <string>fr.rootfs.scrubble</string>
</array>

For local builds, override it with a gitignored copy that adds your team prefix. Create entitlements.macos.local.plist:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
<dict>
    <key>com.apple.security.keychain-access-groups</key>
    <array>
        <string>XXXXXXXXXX.fr.rootfs.scrubble</string>
    </array>
</dict>
</plist>

Replace XXXXXXXXXX with your Team ID (find it via security find-identity -v -p codesigning, in parentheses after your cert name; or by signing once and reading TeamIdentifier from codesign -dv).

Then re-sign after each build:

codesign --force --deep --sign "Apple Development" \
    --entitlements entitlements.macos.local.plist \
    build/macos/Scrubble.app

"Apple Development" matches the first cert of that type in your login keychain. Substitute "Developer ID Application" if you have one, or use your cert's SHA-1 hash if you need to disambiguate.

If you already have stale keychain items from an earlier ad-hoc-signed build, wipe them so they get recreated under the new identity:

for a in token username password apiKey apiSecret; do
    security delete-generic-password -s fr.rootfs.scrubble -a "$a" 2>/dev/null
done

Usage

1. Grab an API key + secret at https://www.last.fm/api/account/create.
2. Launch Scrubble, open Settings.
3. Paste the key + secret. On macOS, click Authorize with Last.fm, complete in browser, click Complete Authorization. Or use the username + password flow.
4. Pick which apps to watch.
5. Play music.

On iOS, preferences live in Settings → Scrubble; changes propagate to the daemon without restarting it.

How it works

Scrobbler observes kMRMediaRemoteNowPlayingInfoDidChangeNotification. After a 5 s grace period (lets MediaRemote populate metadata), it checks MRMediaRemoteGetNowPlayingApplicationIsPlaying — if nothing's actually playing the notification is dropped (this catches stale "now playing" data from apps that just closed). Otherwise it reads the now-playing info, fires track.updateNowPlaying, and schedules track.scrobble for duration * scrobbleAfter seconds later. When the scheduled scrobble fires, it re-verifies the current track tuple against MediaRemote and re-checks IsPlaying, so paused or skipped tracks are dropped. 403s trigger an automatic mobile-session re-auth if a password is stored; everything else surfaces as the failure notification.

Project layout

include/                Shared headers
src/                    Implementation
  main.m                Entry point — macOS NSApp / iOS daemon
  Scrobbler.m           MediaRemote observer + Last.fm client
  CredentialStore.m     Keychain + NSUserDefaults persistence
  MetadataFilter.m      Regex cleanup of track titles
  ScrubbleMacSettings.m macOS settings window
ScrubblePrefs/          iOS preference bundle
assets/                 Icons
layout/                 iOS LaunchDaemon plist + Debian metadata
Makefile                iOS build (Theos)
Makefile.macos          macOS build (clang)