Postgres is the substrate. Event sourcing, bitemporality, hash-chaining are patterns on top of it, not exotic infrastructure.

Rationale High confidence

Boring, proven, operable by a tiny team. XTDB rejected in ADR-0003 on operational-maturity grounds, not capability.

• Source: docs/adr/0003-postgres.md

History

• Proposed human + AI
  Boring, proven, operable by a tiny team. XTDB rejected in ADR-0003 on operational-maturity grounds, not capability.
  28 Aug 2026
• Ratified human + AI
  Approved by Project steward
  28 Aug 2026