Caching

Redis is a cache only when loss is safe:

• Feed user-profile cache (FEED_USER_PROFILE_CACHE_*), invalidated by profile events.
• Media music search cache and ingest staging.
• Messaging presence (ephemeral).

Source of truth stays in Postgres. A cache miss loads from the owner service or from the local projection. Do not cache authorization decisions past the request without a revocation story. Access tokens are short-lived instead.

HTTP responses for private data are not cached at Kong. Public post preview and legal pages can be cached at the website CDN because they are public documents.