The new Datadog Agent (dd-agent 4.0.0) has been released, providing enhanced visibility into application stacks through its JMX collector and improved metrics collection from existing integrations such as PostFix, Couchbase, NGINX, Postgres, Cassandra, Tomcat, Solr, ActiveMQ, and HAProxy. The new Agent includes features like long-lived connections for NGINX, deadlocks detection in Postgres, temporary file allocation metrics in Postgres, per-column-family basis metrics in Cassandra, generic JMX metric collection methods for other integrations, aggregated backend metrics for HAProxy, and per-bucket metrics for Couchbase. These updates were made possible through contributions from the community and beta testing support.