Christian Arango
Side projects

Side project · Desktop app

Cherify

Learning a song by ear means pausing, rewinding, and guessing chords. Cherify separates the voice from the band, transcribes the lyrics, detects the chords in the accompaniment, and lines both up in a sheet you can practice with. It works offline, with cloud services as an optional upgrade.

Author
Christian Arango
Role
Product Owner and builder, with Claude Code
Platform
Windows · Python
Status
Version 0.9.0 · July 2026
Pick a song and the app chooses the best engine available. Without keys, it runs in local mode.

The problem

Lyrics and chords rarely arrive together, or in time

Lyrics sites skip the chords, chord sites skip the timing, and a full mix confuses both. I wanted one sheet where each phrase shows the chords that sound under it.

What I built

Separate first, then transcribe and listen for chords

  • Separation

    Voice and band, apart

    Demucs splits the track. The clean voice feeds the transcription, and the accompaniment feeds chord detection.

  • Lyrics

    Phrases that keep their timing

    faster-whisper transcribes each phrase with its timestamps. Lyrics you paste in become the source and are aligned to the audio.

  • Practice

    A practice tab

    A player with transposition, simplified chords, variable tempo, and export.

Each service is listed with exactly what it receives.
See how each engine is chosen
README.mdpowershell
$env:CHERIFY_TRANSCRIPTION_PROVIDER = "auto"  # auto, openai o local
$env:OPENAI_TRANSCRIBE_MODEL = "gpt-4o-transcribe-diarize"
$env:CHERIFY_CHORD_PROVIDER = "auto"  # auto, klangio o local
$env:WHISPER_MODEL = "large-v3-turbo"
In automatic mode, each engine falls back to its local version when the cloud option isn’t available.

Decisions

Local first, the cloud when it helps

  • An offline fallback

    Automatic mode uses cloud transcription and chord recognition when a key is set, and local open-source models when it isn’t.

  • Keys never touch the disk

    Advanced users can add their own keys. They stay in memory until the app closes, and none ships inside the installer.

  • No invented chords

    Imported text without chords stays that way. The app never makes up a progression.

Where it stands

The installer is ready; chords still need a human ear

Version 0.9.0 ships as a Windows installer that doesn’t need administrator rights. Dense mixes, alternate tunings, and complex extensions can still need a correction by hand.