The closed/hosted/schema-rich extreme: everything is a block (UUID id,
type, properties, ordered child content, single parent), pages are blocks
and database rows are pages with a schema, Postgres-backed hosted SaaS.
Databases add typed properties + relations + rollups + formulas across
many views = the apex of wiki-page-as-structured-record. Extension model
has no in-app plugin runtime; the only extensibility is the external REST
API (+ webhooks 2026) inside a tight envelope (~3 rps, eventual
consistency, recursive child fetch, scoped/revocable per-page grants).
Adds the third attachment mode (external-API-only) alongside file-store
(Obsidian/TWiki) and in-engine host (Roam/XWiki); Notion enforces no
silent remote mutation via scoped grants. Added UC-57 (attach closed
external-API-only shard w/ operational envelope + scoped grant), UC-58
(typed database w/ schema+relations+views, no flattening), UC-59
(lossy-aware translation w/ fidelity report); enriched
UC-31/34/36/39/50/51/52/54/56. Boundary: one external-API candidate shard,
best as projection/mirror/overlay/backup, not a substrate and not the
federation layer.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
