Deterministic data is the bedrock under every test, demo, and dev server.

Last chapter we wired the SSE event contract. Now we step back to something quieter but just as load-bearing. Deterministic means the same seeder run always produces the same resource graph - same IDs, same references, same values. That is what lets a test assert on a known ID, gives a demo a stable patient roster, and makes every developer's local server identical.

The four disciplines that protect it

And a clean reset underneath them all