diff --git a/drpc.yml b/drpc.yml
index 1cfeafc2..d2371ab3 100644
--- a/drpc.yml
+++ b/drpc.yml
@@ -39,6 +39,8 @@ services:
     #  - "2449:2449"
     environment:
       DSHACKLE_LOG_LEVEL: ${DSHACKLE_LOG_LEVEL:-info}
+      # Cap JVM heap (image default is -Xms1024M with no -Xmx).
+      JAVA_OPTS: "-Xms1g -Xmx4g"
     labels:
       - "prometheus-scrape.enabled=true"
       - "prometheus-scrape.port=8081"