diff --git a/deploy.sh b/deploy.sh
index c2eac79..be95042 100755
--- a/deploy.sh
+++ b/deploy.sh
@@ -8,11 +8,17 @@
 set -euo pipefail
 cd /opt/performancewest
 
-SERVICES="${@:-site api workers proxy-relay}"
+SERVICES="${@:-site api workers proxy-relay listmonk-hc}"
 
-# proxy-relay is an upstream image (no build context). Build everything else,
-# but always include it in the `up` set so the healthcare proxy sidecar runs.
-BUILD_SERVICES="$(echo "$SERVICES" | tr ' ' '\n' | grep -v '^proxy-relay$' | tr '\n' ' ')"
+# proxy-relay and listmonk-hc are upstream images (no build context). Build
+# everything else, but always include them in the `up` set so the healthcare
+# proxy sidecar and the healthcare-stream Listmonk run.
+# NB: listmonk-hc needs a one-time DB setup the first time it is deployed:
+#   docker compose exec api-postgres psql -U pw -d postgres -c 'CREATE DATABASE listmonk_hc OWNER pw;'
+#   docker compose run --rm --entrypoint /bin/sh listmonk-hc -c './listmonk --install --idempotent --yes --config /listmonk/config.toml'
+# then configure its 3 SMTP servers (hc ports 2526/2527/2528). See
+# docs/healthcare-email-stream-plan.md.
+BUILD_SERVICES="$(echo "$SERVICES" | tr ' ' '\n' | grep -vE '^(proxy-relay|listmonk-hc)$' | tr '\n' ' ')"
 
 echo "=== Pulling latest from git ==="
 git pull origin main
diff --git a/docker-compose.dev.override.yml b/docker-compose.dev.override.yml
new file mode 100644
index 0000000..4daf9f9
--- /dev/null
+++ b/docker-compose.dev.override.yml
@@ -0,0 +1,17 @@
+# Dev-only overrides. Dev shares the host with prod and historically used its
+# own postgres data volume (dev-pgdata) and no host-port bindings. The canonical
+# (prod) compose uses api-pgdata + host ports; pin dev back to its own data and
+# drop the clashing host ports. !override replaces base lists.
+services:
+  api-postgres:
+    ports: !override []
+    volumes: !override
+      - dev-pgdata:/var/lib/postgresql/data
+  listmonk:
+    ports: !override []
+  listmonk-hc:
+    ports: !override []
+volumes:
+  dev-pgdata:
+    external: true
+    name: performancewest-dev_dev-pgdata
diff --git a/infra/postfix/pw-hc-rampcap.sh b/infra/postfix/pw-hc-rampcap.sh
new file mode 100644
index 0000000..cff737b
--- /dev/null
+++ b/infra/postfix/pw-hc-rampcap.sh
@@ -0,0 +1,46 @@
+#!/bin/bash
+# Ramp the listmonk-hc hourly send cap in lockstep with the healthcare IP warmup.
+#
+# The HEALTHCARE HOT stream sends from fresh dedicated IPs (.107/.108/.109), so
+# even though institutional B2B mail tolerates far more volume than consumer
+# cold mail, we still warm these IPs before hitting the 10k/day ceiling. This is
+# the hc analogue of /usr/local/bin/pw-listmonk-rampcap, driven off a SEPARATE
+# warmup stamp (/etc/postfix/hc-warmup-start) and writing a SEPARATE Listmonk
+# DB (listmonk_hc), so the trucking ramp/cap and the healthcare ramp/cap are
+# fully independent.
+#
+# Steady-state target (institutional, 3 IPs):
+#   day 0-1 : ~1,000/day -> 100/h
+#   day 2-4 : ~3,000/day -> 300/h
+#   day 5-9 : ~6,000/day -> 600/h
+#   day 10+ : ~10,000/day -> 1000/h  (the chosen ceiling)
+set -euo pipefail
+
+STATE=/etc/postfix/hc-warmup-start
+COMPOSE_DIR=/opt/performancewest
+DB=listmonk_hc
+PGPASSWORD=${DB_PASSWORD:-pw_dev_2026}
+
+[ -f "$STATE" ] || { echo "no hc warmup stamp ($STATE); run hc_stream_setup.sh first"; exit 1; }
+START=$(cat "$STATE"); NOW=$(date +%s); DAYS=$(( (NOW - START) / 86400 ))
+
+if   [ "$DAYS" -le 1 ]; then RATE=100
+elif [ "$DAYS" -le 4 ]; then RATE=300
+elif [ "$DAYS" -le 9 ]; then RATE=600
+else RATE=1000; fi
+
+cd "$COMPOSE_DIR"
+psql() { PGPASSWORD=$PGPASSWORD docker compose exec -T -e PGPASSWORD=$PGPASSWORD api-postgres \
+           psql -U pw -d "$DB" -tAc "$1"; }
+
+CUR=$(psql "SELECT value FROM settings WHERE key='app.message_sliding_window_rate';" 2>/dev/null || echo "")
+if [ "$CUR" != "$RATE" ]; then
+  psql "UPDATE settings SET value='$RATE' WHERE key='app.message_sliding_window_rate';
+        UPDATE settings SET value='\"1h\"' WHERE key='app.message_sliding_window_duration';
+        UPDATE settings SET value='true' WHERE key='app.message_sliding_window';" >/dev/null
+  docker compose restart listmonk-hc >/dev/null 2>&1 || true
+  logger -t pw-hc-rampcap "day $DAYS -> listmonk-hc cap ${RATE}/h (was ${CUR}/h)"
+  echo "$(date '+%F %T') hc-rampcap: day=$DAYS cap=${RATE}/h (changed from ${CUR}/h, listmonk-hc restarted)"
+else
+  echo "$(date '+%F %T') hc-rampcap: day=$DAYS cap=${RATE}/h (no change)"
+fi
diff --git a/scripts/deploy-dev.sh b/scripts/deploy-dev.sh
index 77bea38..11f074a 100755
--- a/scripts/deploy-dev.sh
+++ b/scripts/deploy-dev.sh
@@ -60,12 +60,20 @@ done
 # and not overwritten.
 rsync -avz -e "$SSH" docker-compose.yml "$REMOTE:$DEV_DIR/docker-compose.yml"
 
+# Dev-only compose override: dev shares the host with prod, so it must NOT bind
+# the prod host ports (5432/9100/9101/...) and must use its own postgres data
+# volume (dev-pgdata). Shipped as docker-compose.override.yml (compose auto-loads
+# it). Without this, syncing the canonical compose makes dev's api-postgres try
+# to rebind prod's :5432 and switch volumes -> stack breakage. See
+# docs/healthcare-email-stream-plan.md.
+rsync -avz -e "$SSH" docker-compose.dev.override.yml "$REMOTE:$DEV_DIR/docker-compose.override.yml"
+
 echo ""
 echo "=== Rebuilding containers ==="
 
 # proxy-relay is an upstream image (no build context); `up --build` skips the
 # build for it but still (re)creates it from the compose definition.
-$SSH "$REMOTE" "cd $DEV_DIR && sudo docker compose up -d --build api site workers proxy-relay"
+$SSH "$REMOTE" "cd $DEV_DIR && sudo docker compose up -d --build api site workers proxy-relay listmonk-hc"
 
 echo ""
 echo "=== Deploy complete ==="