The native SoundCraft session document, .scraft JSON schema and typed reader/writer. Session and its nested types are the wire representation; the library checks format_version before parsing, deserializes the document directly (without building a serde_json::Value tree), then sanitizes and validates the resulting session. Session::to_json writes the same pretty JSON representation.

The crate retains SoundCraft's serialized enum names, defaults, compatibility behavior for older fields, 256 MiB session byte limit, character limits, and duplicate/exhausted ID checks. Its time fields use craft_time::soundcraft, the exact sample-index time API retained by craft-time. MIDI sequence values use craft-midi's serde representation.

The application still maps sessions to UI state, engine state, media paths and audio pools. The session schema and its format-specific parsing, writing, sanitization and validation live here.