Written from direct SSH inspection of both real clusters (node1-3 prod HA,
dev-k8s-1-3 dev) done while building the GitLab CI + ArgoCD pipeline (MR
!1) - not re-derived from the aspirational docs/manifests that predated
that inspection.
ARCHITECTURE.md: system diagram (clients, both clusters, Stalwart, EJBCA
CA, the CI+ArgoCD flow) plus the storage-coupling fact that everything
else hinges on - 4 RWO PVCs + strategy:Recreate is why the app is
single-replica today.
SANDBOX-DEV-MANUAL.md: day-to-day branch/MR/CI/ArgoCD flow, one-time
bootstrap, troubleshooting, and what's explicitly out of scope for normal
dev work (the CA, the still-inert prod overlay).
PRODUCTION-SCALE-OUT-PLAN.md: phased path to a 100k+-user production
deployment on node1-3 - breaking the storage coupling first (rook-ceph
CephFS RWX as the fast path, migrating mutable state into the
already-installed-but-unused CNPG Postgres as the correct one), then
autoscaling, Stalwart's own scaling track, networking/edge, the
observability gap (none found on either cluster), security hardening,
load testing, DR, and the go-live sequence. Includes a "scale at any
time" manual lever, not just HPA.
