GoKawiil24 May, 2026
Containers are fun. The ecosystem is incredibly open, with the internals right there for anyone to explore. Once you wrap your head around the specifications, you unlock the power to build custom tools and may even discover unexpected use cases. Speaking of “unexpected use cases”, today I have a demo to share: a web application that builds containers right in your browser, relying only on client-side code.
Try it out
Seeing is believing, so why don’t you head to the demo and build a container? You will be able to:
Pick a base image Specify a shell script to run upon container startup Export the resulting image as a tar file, which you can then load into docker
Important: this is a research prototype, don’t use it for anything serious. If you need something production-ready, let’s talk.
How does it work?
Container images are just sets of files (see this article for a dissection). We can download them, unpack them, manipulate them, and repack them, all without leaving the browser! The possibilities are endless, as long as you are able to build your layers inside the browser’s sandbox.
There is little more to say, really. If you try out the demo, you will see build logs describing each build step. Also, the source code of the builder is available here, in case you are interested in the gory details.
Beyond browsers
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