diff --git a/docs_build/dev/ProjectInstructions/addendums/postgres_only.md b/docs_build/dev/ProjectInstructions/addendums/postgres_only.md
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+SQLite is deprecated.
+
+Game Foundry Studio standard database:
+PostgreSQL
+
+Rules:
+- No new SQLite implementations
+- No new SQLite dependencies
+- Existing SQLite references are technical debt
+- New persistence work targets PostgreSQL
+- PRs introducing SQLite should be rejected