meloDL

meloDL is a native macOS app for downloading and converting audio with a clean, settings-first workflow.

Platform

• macOS 15.5+ (SwiftUI desktop app)

What it does

• Accepts media URLs and downloads audio tracks, including playlists.
• Supports many websites via yt-dlp, including YouTube (Music), SoundCloud, TikTok, Instagram, and X (Twitter) and many more.
• Full supported website list: https://github.com/yt-dlp/yt-dlp/blob/master/supportedsites.md
• Converts to MP3, M4A, FLAC, WAV, or OGG, with a quality setting.
• Embeds artist, title, album, and related tags. MP3, M4A, and FLAC can also embed artwork.
• Supports playlist downloads with queue and status. Fast mode downloads several playlist tracks at once.
• Runs more than one download session at a time, and keeps session history so a batch can be reopened later.
• Lets you pick the destination for the next download, including folders already in the library index.
• Preview a finished track, or reveal it in Finder.
• Trim a finished track on a waveform: zoom and drag to choose the section, preview it, then save a new file or replace the original. Replacing moves the old file to the Trash, and tags and artwork stay. MP3, M4A, and OGG are cut without re-encoding. FLAC and WAV are sample-accurate.
• Prevents obvious re-downloads by checking an indexed local library before downloading.
• Supports duplicate cleanup workflows backed by full library indexing and byte-level audio hashing.
• Supports Rekordbox XML import to improve duplicate matching for DJ workflows.
• Uses staged duplicate-review sessions so changes can be reviewed, adjusted, and confirmed before final cleanup. Cards can be swiped or dragged aside.
• Includes a short post-action undo window for smart cleanup actions.
• Can run from the menu bar only, launch at login, post session notifications, and open the download folder when a batch finishes.
• Supports automatic update checks for bundled download binaries (yt-dlp, ffmpeg, ffprobe).

Architecture overview

Download pipeline

• meloDL uses bundled command-line tools:
  • yt-dlp
  • ffmpeg / ffprobe
• The app orchestrates these tools through Process execution in Swift.
• For playlist URLs, the app can prefetch entries and process multiple items.
• Finished tracks can be previewed or trimmed in the app. Trimming runs ffmpeg on the local file.

Library indexing and duplicate resolution

• Users can define library paths that are indexed for duplicate-aware download decisions.
• The index supports deeper duplicate cleanup by hashing raw audio bytes for high-confidence matching.
• Rekordbox XML exports can be imported to assist duplicate resolution in existing DJ libraries.
• Duplicate actions are staged for manual review before confirmation, with an undo grace period after smart cleanup.

Binary updates (tool updates)

• GitHubUpdateService checks GitHub releases for:
  • yt-dlp/yt-dlp
  • eugeneware/ffmpeg-static
• Updated binaries are downloaded and replaced in Application Support.
• Version metadata is tracked in Application Support/meloDL/versions.json.

App updates (Sparkle)

• The macOS app itself updates through Sparkle.
• Sparkle reads an update feed (appcast.xml) from the URL configured in Info.plist (SUFeedURL).
• Each app release should publish:
  • A signed (and ideally notarized) release artifact (DMG/ZIP)
  • A corresponding appcast.xml entry generated by Sparkle tooling

Privacy

See PRIVACY.md for the basic privacy and data-handling disclaimer.

License

MIT. See LICENSE.