A Coolify deploy starts the new container and stops the old one only once
the new one is healthy, so for about half a minute two copies of this app
watch the chain. On 25 September, 06:26 CT, both saw Marty's $5 purchase:
two confirmation emails, and the Five Dollar Friday bonus granted twice
(+100 and +100, nineteen seconds apart). Every dedupe until now lived in
process memory or a JSON file on the volume; a second process shares
neither in time.
marks.js is the shared version: a row in MySQL that only one INSERT IGNORE
can win. The chain-event fan-out claims 'ev:<tx>:<logIndex>' before the
email, Telegram post, Friday bonus and sponsor sync; the in-memory feed
stays per instance. The Friday scheduler claims its Thursday email, kickoff
and wrap-up the same way, with the file marker kept as the second line of
defence and the thing an operator can edit by hand. Without a database it
degrades to a per-process Set, which is exactly the old single-instance
behaviour.
Proven on the production MySQL before deploy: first insert 1 row, second 0.
Marty's duplicate 100 credits reversed with a labelled adjust row; no other
member was double-granted.
Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
martbost