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 # runner-images
 
-This is the default image used by [act_runner](https://gitea.com/gitea/act_runner) to run workflows.
+Official docker images used by [act_runner](https://gitea.com/gitea/act_runner) to run workflows.
 
-If the tool you need does not exist in this image, please create an [issue](https://gitea.com/actions/runner-images/issues) to report it or send a [pull request](https://gitea.com/actions/runner-images/pulls) to add it.
+Currently, we have not chosen to build the image ourselves, as [catthehacker/docker_images](https://github.com/catthehacker/docker_images) has done an excellent job of this.
+We don't need to reinvent the wheel.
+
+So, we build images from `catthehacker/ubuntu:*` or `node:*`, then install additional packages if needed for act_runner to work.
+
+## Images
+
+We provide two kinds of images, "default" and "slim" (and maybe more like "full" in the future).
+
+### Default images
+
+Default images are based on `catthehacker/ubuntu:*`, and are used by default in act_runner.
+They contain most of the tools needed to run workflows and are always recommended if your runner is not disk-space constrained.
+
+| Tag                                 | Base                             | Size                                                                                           |
+|-------------------------------------|----------------------------------|------------------------------------------------------------------------------------------------|
+| `gitea/runner-images:ubuntu-latest` | `catthehacker/ubuntu:act-latest` | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-latest?label=size) |
+| `gitea/runner-images:ubuntu-22.04`  | `catthehacker/ubuntu:act-22.04`  | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-22.04?label=size)  |
+| `gitea/runner-images:ubuntu-20.04`  | `catthehacker/ubuntu:act-20.04`  | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-20.04?label=size)  |
+
+### Slim images
+
+Slim images are based on `node:20-bookworm`.
+They contain Node.js to run basic workflows and set up more development tools if needed.
+Their size is much smaller, which is friendly to disk-space constrained runners.
+
+| Tag                                      | Base               | Size                                                                                                |
+|------------------------------------------|--------------------|-----------------------------------------------------------------------------------------------------|
+| `gitea/runner-images:ubuntu-latest-slim` | `node:20-bookworm` | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-latest-slim?label=size) |
+| `gitea/runner-images:ubuntu-22.04-slim`  | `node:20-bookworm` | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-22.04-slim?label=size)  |
+| `gitea/runner-images:ubuntu-20.04-slim`  | `node:20-bullseye` | ![size](https://img.shields.io/docker/image-size/gitea/runner-images/ubuntu-20.04-slim?label=size)  |