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README.md

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+# kontain.me
+
+[kontain.me](https://kontain.me) serves Docker containter images generated
+on-demand at the time they are requested.
+
+`docker pull kontain.me/random:latest` serves an image containing random data.
+By default the image contains one layer containing 10 MB of random bytes.  You
+can request a specific size and shape of random image. For example,
+`kontain.me/random:4x100` generates a random image of 4 layers of 100 random
+bytes each.
+
+`docker pull kontain.me/ko/[import path]` serves an image containing a Go
+binary fetched using `go get` and built into a container image using
+[`ko`](https://github.com/google/go-containerregistry/blob/master/cmd/ko/README.md).
+For example, `docker pull
+kontain.me/ko/github.com/google/go-containerregistry/cmd/ko` will fetch, build
+and (eventually) serve a Docker image containing `ko` itself. _Koception!_
+
+The registry does not accept pushes and does not handle requests for images by
+digest. This is a silly hack and probably isn't stable. Don't rely on it for
+anything serious.
+
+## How it works
+
+The backend is implemented using [Google Serverless
+Containers](https://g.co/serverlesscontainers), with an App Engine Go 1.11
+frontend to provide SSL on a custom domain (source in [`fwd/`](./fwd/)).
+
+When the app receives a request for an image manifest, it parses the request
+and generates layers for the requested image, writing the blobs to [Google
+Cloud Storage](https://cloud.google.com/storage/). After it receives the
+manifest, `docker pull` fetches the blobs. The app simply redirects to Cloud
+Storage to serve the blobs. Blobs are deleted after 10 days.