Nexus-CORE is a Fedora-based desktop for people who want Linux to tell
them what is going on. Before anything changes, Nexus says what it
will do and what it will not do, and nothing happens until you add
--apply or press the button. Every change is written down in
nexus history.
It is a preview made by one person, tested on a few laptops and in
virtual machines. Read the known limits
before installing, and keep a backup of anything that matters.
Download
| Edition | Desktop | For | Download |
|---|
| KDE Plasma | KDE Plasma | the full desktop, gaming included; 4 GB RAM or more | Preview 3 ISO |
| Minimal | LXQt | older computers, from 2 GB RAM | Preview 3 ISO |
Checksums are on the release page
and the website. Check the file before writing it to a USB stick:
sha256sum nexus-core-preview3.iso
Needs a 64-bit PC with UEFI. Secure Boot can stay on.
About the disk: an empty disk is used whole. Next to another
Linux with 30 GB or more free in one piece (UEFI, GPT disk), Nexus
installs into the free space and leaves the other system alone. If
anything else is on the disk, Windows included, the installer asks
before touching anything. Dual boot with Windows is not supported.
What you get
- It asks what the machine is for. At first start you pick add-ons
(media, gaming, development, school, cybersecurity, VPN). Nexus shows what
each would add on your hardware and installs nothing until you agree.
- Nexus Shop. Flathub, Fedora and RPM Fusion side by side, with
what Nexus suggests and why: who packaged the app, whether it needs a
restart, whether it is open source. Before every install, a "What
Nexus will do / It will not" screen.
- Updates on your terms. A new signed image is built every week
with Fedora's latest fixes. Your machine checks daily and tells you.
Nothing is installed, and the computer never restarts by itself,
until you say so. The previous version stays in the boot menu.
- Next to your Linux.
sudo nexus dualboot lists the other systems
on the disk; sudo nexus dualboot 1 --apply restarts straight into
one, once. Each one starts through its own signed loader, so Secure
Boot stays on.
- Encrypted by default, with signed images: an installed machine
refuses an update that Nexus-CORE did not sign.
nexus doctor checks clock, memory, storage, services, updates
and encryption, and says what to do about anything wrong.nexus gamecheck <game>: will it run, what its anti-cheat
allows, and what it can read about your computer. Reports only.- No accounts, no tracking.
The nexus command
nexus this machine in a few lines
nexus guide how to work this system
nexus doctor is anything wrong, and what to do
nexus update [--apply] what is new; take it
nexus app install|remove <flathub id> [--apply]
nexus setup [add-ons] [--apply]
nexus dualboot [add | remove | <number>] [--apply]
nexus gamecheck <game> will it run here, and what it can see
nexus language [list | add | set] [--apply]
nexus history every change Nexus has made
nexus install | remove | options | why | largest | services | hardware | secureboot
Every command only reads and explains. Only --apply changes
anything. nexus --help lists the rest.
An example, before anything is changed:
$ sudo nexus dualboot 1
What Nexus will do
Restart the computer now, into Linux Mint 22.3
Only this once: the next restart starts Nexus again
It will not
Change the order the computer starts in
Close your apps for you first: save your work
Nothing has been changed. To restart:
sudo nexus dualboot 1 --apply
How it is built
- Fedora bootc. The system is a container image
(
image/Containerfile), built from a profile: a list of what the
machine should be able to do, resolved to Fedora packages. The KDE
and minimal editions build from the same file with one argument
changed.
- Updated as one piece. An update downloads a whole new image and
switches to it at the next restart; the old one stays in the boot
menu. Nothing is half-updated.
- Signed. Images are signed with cosign by the weekly workflow
(
.github/workflows/weekly-image.yml), and installed machines are
set to refuse unsigned ones.
- The installer ISO is made with Fedora's
bootc-image-builder:
./image/build-installer.sh. Every build writes down what went into
it (image digest, Nexus version, builder digest, ISO checksum).
- The kernel is Fedora's, with Fedora's signature, which is why it
boots with Secure Boot on.
The nexus tool itself is C++20 and Qt 6 (the Shop). It decides and
explains; Fedora's own tools (rpm-ostree, flatpak, bootc) do the work.
Building
cmake -S . -B build && cmake --build build
ctest --test-dir build
./build/cli/nexus doctor
Needs a C++20 compiler and CMake 3.20, Qt 6 for the Shop, and
GoogleTest for the tests (-DNEXUS_BUILD_TESTS=OFF to skip).
576 automated tests.
To build an installer ISO from a published image:
PROFILE=kde IMAGE=ghcr.io/davidosdas-official/nexus-core:kde ./image/build-installer.sh
It needs about 20 GB of free disk space.
Layout
cli/ the nexus command
gui/ Nexus Shop (Qt Quick)
core/ the model: capabilities, resolution, conflicts
system/ reading real systems: rpm, dpkg, flatpak, bootc, disks, dual boot
hardware/ what the machine is: devices, encryption, secure boot
components/ profiles and add-ons, as data
image/ the bootc image, installer, first start, updates, boot menu
tests/ unit and differential tests
docs/ decisions and specifications
docs/specifications/00-decisions.md has the reasoning that is not
recoverable from the code.
Reporting problems
Open an issue
with what you did, what happened, and the output of nexus doctor.
For anything security-related, see SECURITY.md.
Licence
The code is under the GNU General Public License, version 3. See
LICENSE.
The name Nexus-CORE and the node-graph N logo are trademarks and are
not covered by the GPL: a changed version has to be renamed. See
TRADEMARKS.md.
Made by DAVIDOSDAS.
