Monedula Flock

Free tools for Apache Kafka

The CLIs and the broker plugin are open source, and the Kafka Simulator runs in your browser. The blog and its RSS feed announce new tools.

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The tools

Go, AGPL-3.0, v0.1.0

monedula-gitops

GitOps for Apache Kafka: topics, access, quotas, schemas, SCRAM users and Confluent RBAC, from a CLI or a Kubernetes operator.

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Go, AGPL-3.0, v0.10.0

monedula-acl-rbac-converter

A CLI that converts Apache Kafka ACLs into Confluent RBAC role bindings through a checksummed plan and verifies effective access before any ACL is deleted.

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Java, AGPL-3.0, v0.10.0

monedula-metrics-reporter

A Kafka MetricsReporter plugin that ships broker, JVM and KIP-714 client metrics over OTLP; a collector outage never blocks Kafka.

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Go, Apache-2.0, v0.10.0

monedula-sim-link

A read-only Go CLI that turns a real Kafka cluster into a shareable Kafka Simulator link, with an MCP server for AI agents.

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Free, runs in your browser

Kafka Simulator

An interactive, deterministic Apache Kafka simulator in the browser: break a cluster, scrub the timeline and read why it reacted.

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The name

Monedula is Latin for the jackdaw, the bird hiding in Kafka's name (kavka is Czech for jackdaw). Jackdaws are almost never seen alone, so the tools share one name: Monedula Flock.

A jackdaw roost leaves at dawn once the chorus of calls is loud enough.¹ The two tools that change a cluster, monedula-gitops and monedula-acl-rbac-converter, can wait for agreement too: both keep desired state and plans in files that can go through a reviewed pull request.

Dibnah et al. (2022), "Vocally mediated consensus decisions govern mass departures from jackdaw roosts", Current Biology. doi:10.1016/j.cub.2022.04.032