Update readme

Author: macropin

README.md

@@ -2,8 +2,66 @@
 
 Docker image of [yahoo/CMAK](https://github.com/yahoo/CMAK).
 
-## Testing and Development
+This repository builds and publishes a Docker image for CMAK (Cluster Manager for Apache Kafka, previously known as Kafka Manager).
 
-Some tests are provided in [tests/](tests/).
+## Version
 
-A `docker-compose.yaml` is provided with Zookeeper and Kafka. Once running a cluster can be added by setting the "Cluster Zookeeper Hosts" to `zk:2181`.
+*   CMAK: `3.0.0.6`
+
+## Usage
+
+### Running with Docker
+
+To run the image:
+```bash
+docker run -p 9000:9000 -e ZK_HOSTS=your_zookeeper_hosts panubo/cmak
+```
+The CMAK web interface will be available at http://localhost:9000.
+
+### Development Environment
+
+A `docker-compose.yaml` is provided for a quick development and test setup. It includes Zookeeper, Kafka, and the CMAK image.
+
+To start the services:
+```bash
+docker-compose up
+```
+Once running, you can add a new cluster in the CMAK UI.
+*   **Cluster Zookeeper Hosts:** `zk:2181`
+
+## Building the Image
+
+To build the Docker image locally, you can use the provided Makefile:
+```bash
+make build
+```
+
+## Configuration
+
+The CMAK instance can be configured using environment variables. The primary variable is `ZK_HOSTS` to point to your Zookeeper ensemble.
+
+| Environment Variable | Description                      | Default   |
+| -------------------- | -------------------------------- | --------- |
+| `ZK_HOSTS`           | Zookeeper hosts for CMAK to use. | `zk:2181` (in docker-compose) |
+
+## Testing
+
+The project includes a test suite using `bats`. The tests are located in the `tests/` directory.
+
+To run the tests:
+```bash
+make test
+```
+
+## CI/CD
+
+This repository uses GitHub Actions to automatically build and publish multi-arch (`linux/amd64`, `linux/arm64`) Docker images to:
+
+*   `quay.io/panubo/cmak`
+*   `public.ecr.aws/panubo/cmak`
+
+Images are tagged based on git branches and tags.
+
+## Status
+
+Stable and production ready.