How to: CI/CD Related Improvements
#### Tips for reducing the size of the image

- Start the container as usual, and remove unnecessary files. A useful way
  to do this is to use `du -sh *` starting from the `/` directory, and find
  large directories where files can be removed. E.g. unnecessary cached files,
  Xcode platforms, etc.
- Once you are satisfied with the amount of free space, enable trim with `sudo trimforce enable`, and reboot.
- Zero out the empty space on the disk with `dd if=/dev/zero of=./empty && rm -f empty`
- Shut down the VM and copy out the qcow image with `docker cp stoppedcontainer:/home/arch/OSX-KVM/mac_hdd_ng.img .`
- Run `qemu-img check -r all mac_hdd_ng.img` to fix any errors.
- Run `qemu-img convert -O qcow2 mac_hdd_ng.img deduped.img` and check for errors again
- **OPTIONAL:** Run `qemu-img convert -c -O qcow2 deduped.img compressed.img` to further compress the image. This may reduce the runtime speed though, but it should reduce the size by roughly 25%.
- Check for errors again, and build a fresh docker image. E.g. with this Dockerfile

```
FROM sickcodes/docker-osx
USER arch
COPY --chown=arch ./deduped.img /home/arch/OSX-KVM/mac_hdd_ng.img
```