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README.md

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+# Custom OS for Programming Contests
+
+This repository contains recipe to customize the Ubuntu 22.04 Jammy
+Jellyfish desktop image for an on-site programming contest.
+
+[![Tests](https://github.com/rebornplusplus/contest-iso/actions/workflows/tests.yml/badge.svg)](https://github.com/rebornplusplus/contest-iso/actions/workflows/tests.yml)
+
+## Installation
+
+You can go two ways about this:
+
+1. Prepare a custom ISO that can re-distributed.
+2. Customize an existing installation.
+
+### Prepare custom ISO with [Cubic](https://github.com/PJ-Singh-001/Cubic)
+
+You can choose to create a customized ISO which can then be simply
+installed in each machine. To do that, follow these simple steps:
+
+1. Download a Ubuntu 22.04 desktop image. Find download options
+   [here](http://releases.ubuntu.com/jammy/).
+2. Launch Cubic, configure and find your way to the console in the
+   chroot environment.  [Learn how to use Cubic](https://askubuntu.com/questions/741753/how-to-use-cubic-to-create-a-custom-ubuntu-live-cd-image).
+3. Copy/clone the repository files in the `/root` directory. Make sure
+   to customize options (user accounts etc.) in [vars.sh](./vars.sh).
+4. Run the [install.sh](./install.sh) script as `root`. It _should_ run
+   non-interactive.
+5. Proceed with Cubic options, compress and generate the iso.
+
+The ISO can now be re-distributed and installed on machines
+independently.
+
+### Customize an existing installation
+
+If you have Ubuntu 22.04 installed on a machine, you can simply run the
+scripts on the OS to customize your instance. The following steps should
+do the trick:
+
+1. Copy/clone the repository files. Make sure to customize options (user
+   accounts etc.) in [vars.sh](./vars.sh).
+2. Run the [install.sh](./install.sh) script as `root`. It _should_ run
+   non-interactive.
+
+## What's inside?
+
+The scripts install the following utilities:
+
+* Compilers
+   - GCC
+   - G++
+   - Python3
+   - Java
+* Editors
+   - Vim
+   - Emacs
+   - Nano
+   - Sublime text
+   - VS Code
+   - Gedit
+* IDEs
+   - Code::Blocks
+   - Geany
+   - PyCharm
+   - Intellij IDEA
+
+Three user accounts are also created:
+
+* admin	(for administrative usage, has sudo rights)
+* main	(for the on-site main contest)
+* mock	(for the mock contest)
+
+There are also some pre-loaded configurations located in the
+[dots](./dots/) directory.
+
+## Contributing
+
+Pull Requests are welcome!
+
+## License
+
+See [LICENSE](./LICENSE).
+
+## TODO
+
+- [ ] Trim down the image. The generated iso is about 6.5G now. Maybe
+  extend the [trim.sh](./scripts/trim.sh) script?
+- [ ] See if the process of creating ISO (with cubic) can be automated.
+  [See context](https://answers.launchpad.net/cubic/+question/677976).