Protocol and library boundaries

Protocol documentation is an evidence notebook. Do not invent packet offsets, MIDI mappings, or format guarantees from product names.

Area	Planned module	Research and validation scope
MIDI	midi, hardware profiles	Port discovery, input/output mapping, device modes, ranges, feedback loops
PRO DJ LINK	prodj-link	Discovery, beat, status, dbserver, precise-position observations
rekordbox	rekordbox	PDB, ANLZ, beatgrid/cues, Device Library Plus as separate format research

Keep packet codecs free of I/O. Normalize decoded observations into domain types while retaining raw source identifiers and uncertainty. Store redacted fixtures with provenance, expected decoding, malformed/truncated cases, and firmware context. Packet replay tools default to offline parsing.

Library ingestion resolves track and analysis identities without making external database layouts part of dj-domain. Import is read-only initially. Missing beatgrids or unsupported formats produce explicit diagnostics rather than synthetic data presented as real analysis.

Evidence template

Each protocol finding records: source URL or capture ID; inspection date; device/firmware; exact byte or message example; expected interpretation; confidence; test fixture; and unresolved alternatives.

Start with the upstream audit. Implement and test only the portions needed by the current milestone. Network emulation remains independent of the virtual audio renderer.