# ADR 0007: Recording Archive and Source Deletion Policy

## Status

Accepted, amended by [ADR 0011](0011-use-meeting-lab-mvp-backend.md)

## Context

Uncompressed WAV recordings require substantial storage space. However, the
original recording must remain available until transcription, diarization and
quality verification have completed successfully.

The system requires a controlled mechanism for compressing recordings and
removing temporary source files without risking data loss.

## Decision

Recordings shall initially be captured in a processing-friendly lossless
format, normally WAV.

After transcription and, when enabled, diarization have completed, the
recording may be converted to an archive format.

The preferred archive formats are:

- FLAC for lossless archival
- Opus for storage-efficient speech archival

MP3 may be supported as an export format but is not the preferred internal
archive format.

The original WAV file may only be deleted after:

1. processing completed successfully,
2. all required transcript artifacts were persisted,
3. the archive file was created successfully,
4. archive integrity was verified,
5. explicit user confirmation was received.

Checksums shall be stored for both source and archive files where practical.

The processing format and the archive format are intentionally separated.

## Consequences

- Temporary WAV files may require significant short-term storage.
- Permanent storage consumption is reduced.
- Lossless and storage-efficient archive profiles can coexist.
- Source deletion remains deliberate and traceable.
- Failed or incomplete processing must never trigger automatic source deletion.