If you would like to use a stable, predictable, manageable and reproducible distribution in your AppVMs, you can install the Gentoo template, provided by Qubes in ready to use binary package. For the minimal and Xfce versions, please see the [Minimal TemplateVMs] and [Xfce TemplateVMs] pages.
After a fresh install, we recommend to [Update the TemplateVM](https://www.qubes-os.org/doc/software-update-vm/). We highlight that the template memory/CPU allocation certainly need to be adjusted in some cases. As Gentoo is a *linux source distribution*, the template needs resources to perform updates or installing any packages. By default, each TemplateVM has *2 VCPUs* for *4000 MB Max memory* allocated. If needed, double those values, *4 VCPUs* for *8000 MB Max memory*. For example, it has been observed failing updates or builds with *4 VCPUs* for *4000 MB Max memory* due to out of memory issue. For more general considerations, we refer to the official [Gentoo Handbook].