diff --git a/docker-compose.dev.yml b/docker-compose.dev.yml
index a3dbd34..ecd32aa 100644
--- a/docker-compose.dev.yml
+++ b/docker-compose.dev.yml
@@ -36,6 +36,10 @@ services:
       # will successfully connect (the reconnect loop retries every 5s).
       NOSTR_TRANSPORT_ENABLED: "true"
       NOSTR_TRANSPORT_RELAYS: '["ws://localhost:5001/nostrrelay/test"]'
+      # Lowered from the 40_000 default just to make sharding easy to
+      # exercise in local tests without seeding hundreds of payments.
+      # Production runs should leave this unset (defaults to 40_000).
+      NOSTR_TRANSPORT_MAX_EVENT_CONTENT_LENGTH: "20000"
       # Auto-credit 1M sats to freshly-created accounts. Required by the
       # transport-driver `--flow subscribe` end-to-end test which pays a
       # FakeWallet invoice between two newly created wallets. Gated to