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+# Upstream sources — discourse
+
+| service | image | source repo | releases / changelog |
+|---------|-------|-------------|----------------------|
+| app | bitnamilegacy/discourse (was bitnami/discourse) | https://github.com/bitnami/containers/tree/main/bitnami/discourse | https://github.com/bitnami/containers/blob/main/bitnami/discourse/CHANGELOG.md |
+| sidekiq | bitnamilegacy/discourse (same image as app) | https://github.com/bitnami/containers/tree/main/bitnami/discourse | https://github.com/bitnami/containers/blob/main/bitnami/discourse/CHANGELOG.md |
+| db | pgvector/pgvector (was postgres) | https://github.com/pgvector/pgvector | https://github.com/pgvector/pgvector/blob/master/CHANGELOG.md |
+| redis | redis | https://github.com/redis/redis | https://raw.githubusercontent.com/redis/redis/8.0/00-RELEASENOTES |
+
+## Standing notes
+- bitnami/discourse was removed from Docker Hub; bitnamilegacy/discourse is the byte-identical archived
+  drop-in. The recipe (PR #1) re-pins to bitnamilegacy/discourse. The cc-ci overlay (compose.ccci.yml)
+  also re-pins the base deploy.
+- postgres major version upgrades require operator action: pg_dumpall backup → undeploy → delete data
+  volume → redeploy → restore. See recipe README "Welcome to hell" section. Do NOT auto-bump postgres
+  more than one major at a time.
+- PR #2 (upgrade-0.8.0+3.5.0) upgrades discourse 3.3.1→3.5.0 and postgres:13→pgvector/pgvector:pg17.
+  That is a 4-major postgres jump; operators MUST follow the manual dump/restore procedure in the README.
+- Redis 8.0 GA supports upgrade from 7.x data files. Discourse uses Redis only as a cache/queue (no
+  persistence modules). Redis 8.0 integrates RediSearch/RedisJSON/etc. as built-ins; discourse does not
+  use those modules so this is transparent.
+- bitnami/discourse:3.3.1 bundles pg_dump v13 internally; if using external postgres >13, backup hooks
+  that call pg_dump from within the app container may emit version-mismatch warnings (non-fatal for
+  simple schemas, but worth noting). The cc-ci ops.py backup test uses psql from the db container,
+  bypassing this.