Behind the pressing plant
Liner Notes
Native Swift, format-specific editors, and a dedicated identification platform. Private Press brings artwork, metadata, and collection health into one workflow: Scan, Repair, Press.
Recorded at
Your audio is never re-encoded.
Pressing edits the metadata layer of MP3, M4A, FLAC, and AIFF files. Native parsers understand ID3 frames, MP4 atoms, FLAC metadata blocks, and AIFF chunks, so the encoded audio passes through without re-encoding.
Verified, recoverable writes
The writer stages a new file beside the original, checks the output and source identity, and records replacement steps in a durable journal. Interrupted replacements can be recovered or brought into Recovery Review. Backups are enabled by default.
Format-native editing
Four dedicated Swift editors understand ID3 frames, MP4 atoms, FLAC metadata blocks, and AIFF chunks. They update the metadata layer while preserving the encoded audio payload.
Keep the booklet
Replacing the front cover preserves supported back-cover and leaflet pictures in MP3, AIFF, and FLAC. M4A editing retains later cover entries. FLAC pressing copies the audio frames without decoding or re-encoding them.
Press history
Artwork source, chosen match, and press outcome are recorded in your collection history. Preview lets you inspect a candidate before a press changes the file.
Verified File Writes
Stage → verify → replace.
Durable records support recovery.
Format-Native Editing
Metadata written. Audio untouched. Bit for bit.
Mastered by
Quality you can inspect.
Private Press measures artwork quality on your Mac. Artwork state, audio quality, match confidence, and sync status contribute to collection health scores. Embedded-artwork status, resolution, and compression help identify covers that need attention.
Embedded or Music-only
Artwork displayed by Apple Music may live only in its database. Private Press distinguishes that from artwork embedded in the media file and flags missing or low-resolution covers for repair.
Resolution and compression
Image dimensions, aspect ratio, file size, and JPEG quantization tables provide concrete quality signals. Small images and heavily compressed covers are flagged for attention.
Edition-aware matching
Album and artist similarity, edition wording, release year, and track count contribute to match confidence. Compare candidates before choosing artwork for a remaster, deluxe edition, compilation, or multi-disc release.
On-device metadata assistance
When Apple Intelligence is available on macOS Tahoe, Private Press uses Apple's on-device language model for metadata-cleanup suggestions and natural-language collection search. Review proposed cleanups before applying them.
Example Collection Health Score
Artwork, audio, match confidence, and sync status.
Mixed from
Three sources. Find the right edition.
Search iTunes, expand to MusicBrainz and Cover Art Archive, or use a configured Discogs connection. Search All brings provider results together, and provider priority lets you shape the order for your collection.
Resilient provider search
Search All tracks provider failures separately and applies cooldowns after repeated errors. Available providers can continue returning candidates while a troubled source waits to retry.
Confidence scoring
Weighted album and artist similarity, edition alignment, track count, and year produce a match score. Confidence helps rank candidates; the artwork and release details are there for you to compare.
Your provider order
Choose provider priority in Settings and review source performance in Insights. Accepted and rejected matches are retained locally to support your collection's search workflow.
3 Providers, Ranked
Illustrative match scores.
Compare the artwork and edition.
Identified by
Your files know what they are. Even when the tags don't.
When tags are missing or misleading, Private Press generates acoustic fingerprints on your Mac. Keynell's identification service combines recording evidence with album metadata to find and rank release candidates, then returns the evidence for review.
Local fingerprinting
Native Swift and Accelerate generate Chromaprint-compatible fingerprints from local audio. Identification requests send fingerprints, durations, and album and track metadata; the media files stay on your Mac.
A dedicated identification platform
Keynell combines cached fingerprint lookups, AcoustID recording matches, and its MusicBrainz mirror. Recording coverage, track order, durations, titles, and release details contribute to weighted candidate scores.
Evidence before repair
Exact, probable, ambiguous, and no-match outcomes keep uncertain releases visible. Candidate selection feeds a metadata-repair proposal so you can review changes before writing them.
Audio Fingerprinting
Local fingerprints.
Recording evidence and release matching.
Produced with
Native Swift. Apple frameworks. Zero linked packages.
The Mac application uses Swift 6 and Apple system frameworks with zero linked third-party packages. Its metadata writers and update pipeline are built in-house. The Swift fingerprint engine uses MIT-licensed Chromaprint classifier and encoding material, plus reference parameters for AcoustID-compatible resampling. Source notices and the DM Mono fonts' OFL attribution ship with the app. Native implementation keeps the dependency surface small and the file-writing path under direct control.
Intelligence
Media
Platform
Infrastructure
Built for the collection
Four format-specific editors. Metadata and artwork writes without an audio-conversion pipeline. Verified updates. Signed release metadata, artifact verification, and a dedicated installer helper. Experimental codec work. Our FLAC module supplies metadata utilities used by shipped pressing and a full pure Swift audio encoder and decoder. Audio conversion remains experimental; pressing preserves the existing audio without invoking those encoder/decoder APIs.
Pressed on
Deep in macOS. Not just running on it.
SwiftUI, AppKit, CoreSpotlight, and AppIntents bring your collection into familiar Mac workflows. Security-scoped access keeps folder permissions tied to the locations you choose.
Spotlight search
Collection albums are indexed into CoreSpotlight so a system search can take you directly into Private Press.
Shortcuts
AppIntents connect collection health, scanning, artwork search, and pressing to Shortcuts, with the same collection and entitlement checks as the app.
Local collection state
SQLite stores collection records, accepted matches, press history, and recovery work locally. Saved state and cached thumbnails carry your workflow across launches.
Distributed by
Your music doesn't live in one place. Neither does Private Press.
Scan, Repair, Press works across local files in Apple Music and the folders you choose on mounted local, external, or NAS volumes. Collection records stay associated with their source, so each workflow operates on the right files.
Apple Music
Reads local tracks through iTunesLibrary and distinguishes embedded artwork from artwork held only by Music. After a press, a separate refresh and verification workflow checks Music's artwork state.
Folders & NAS
Choose a folder on a local disk, external drive, or mounted NAS. Format-specific readers inspect supported files, and security-scoped bookmarks retain authorized access across launches. Pressed artwork travels inside the files your other players read.
Pressed to In development
Your other Mac gets it too.
The Press Sync engine uses Bonjour discovery and direct Mac-to-Mac transfer over Apple's Network framework. Its implementation combines explicit device pairing, authenticated encrypted connections, verified file transfer, and recovery records.
Discover, compare, pair
Bonjour discovers peers on the local network. Pairing compares a code on both Macs, binds the peer's public key, and requires user confirmation. Subsequent sessions authenticate the paired devices with TLS 1.3.
Verified transfer
Chunk checksums and whole-file hashes verify received content. Completion receipts and journaled replacement records distinguish received bytes from a completed destination write.
Content-aware decisions
Audio and artwork evidence guide eligible transfer decisions. Different bytes with equal audio-quality scores remain a review decision. Version records describe divergence without authorizing an overwrite.
Protected by
An update has to prove what it is.
Private Press has its own cryptographically verified update pipeline. The offered release, downloaded disk image, and installed application each pass a separate identity check.
Signed release metadata
Ed25519 signatures bind the release version, build, download URL, artifact size, and SHA-256 digest. The updater verifies candidates before deciding which release is eligible.
Verified artifacts
The downloaded disk image must match its signed size, digest, and artifact signature. The installer checks the app bundle against Keynell's signing identity before replacement.
Recovery-aware installation
A dedicated helper stages the replacement and preserves the previous application for rollback. A post-launch check-in confirms that the new app started.
Built with Swift 6 strict concurrency.
Native tools for the collection you keep.