Mentalnet GNU/Linux

A light, TTY-only GNU/Linux distribution for 90s Intel Pentium-class (i586) machines, built with Buildroot.

The ISO is a live CD: the entire system runs from the CD with a read-only root filesystem, and the same CD carries a built-in hard disk installer (mentalnet-install).

Current release

R1 "FirstStorm" — named after DECO*27's Chūlán First Storm (初嵐～First Storm～).

Versioning

• Major releases bump the R<n> number (R1, R2, ...).
• Minor releases keep the R<n> base version and use the codename as the minor version.
• All codenames are taken from Vocaloid, Hatsune Miku or Kasane Teto songs.

Release	Codename	Song	Notes
R1	Mesmerizer	Mesmerizer — 32ki (Hatsune Miku & Kasane Teto)	Initial release
R1	FirstStorm	Chūlán First Storm (初嵐～First Storm～) — DECO*27	Current — swap-free installer, true i586 support, terminal/input hardening, interrupt-storm fixes

Quick facts

Login	root / mnlinux
Hostname	mentalnet
Kernel	6.12.104-mentalnet-intel32
Media	Live CD with built-in installer
CPU	i586 (Pentium / Pentium MMX) or any newer x86
RAM	128 MB minimum (64 MB usually works)

Building from source

This repository is not a full Buildroot tree — it is an overlay meant to be applied on top of a pristine Buildroot checkout.

1. Download and extract the pristine Buildroot 2025.02.17 LTS tarball (do not use a git checkout of master; this layer is written against 2025.02.17):

   wget https://buildroot.org/downloads/buildroot-2025.02.17.tar.gz
   tar xf buildroot-2025.02.17.tar.gz
   cd buildroot-2025.02.17
   

2. Copy this repository's contents over the extracted tree, preserving paths:

   Source (this repo)	Destination (Buildroot tree)
   board/mentalnet/	board/mentalnet/
   fs/iso9660/grub.cfg	fs/iso9660/grub.cfg — overwrites an upstream file
   .config	.config
   logos/, README.md, LICENSE	same paths (repo-local, not used by the build)

3. Build:

   make
   

   Host dependencies are listed in the Buildroot manual. Outputs land in output/images/ — see the install guide for what each artifact is and how to test it.

The committed .config is based on the default i386 defconfig plus the Mentalnet selections (GRUB2 embedded config, e2fsprogs, getty TERM, and so on). Copying it reproduces the released system exactly; alternatively, start fresh with make menuconfig and roll your own.

Security after install

The default root password is mnlinux — please change it after installing:

passwd

Then, for day-to-day use, create a regular user and give it sudo privileges (sudo is included in the build):

adduser myuser

You have two options to grant sudo:

• Add the user to the sudo group, which the shipped sudoers file already trusts:

  addgroup myuser sudo
  

• Or, if you prefer the classic wheel group, enable it with visudo (uncomment the %wheel line) and add the user to it:

  visudo
  addgroup myuser wheel
  

Verify that sudo works for the new user before locking root — log in as the user and run, for example, sudo ls /.

Once sudo is confirmed working, lock the root account so it cannot be accessed (SSH included):

passwd -l root

Documentation

The full install and test guide — hardware requirements, QEMU testing, the install walkthrough and troubleshooting — lives in board/mentalnet/INSTALL-GUIDE.md.

License

Mentalnet GNU/Linux — the scripts, configuration, documentation and artwork added on top of Buildroot (board/mentalnet/, logos/, README.md, LICENSE, and the modifications made to Buildroot files) — is

Copyright (C) 2026 Mark Robillard Jr (MARKMENTAL)

SPDX-License-Identifier: GPL-3.0-or-later

This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. See LICENSE.

The underlying Buildroot tree remains under its original license (see COPYING, GPL-2.0-or-later); we claim no rights over it. This repository is an overlay meant to be applied on top of a pristine Buildroot 2025.02.17 tree, not a full fork.

The OS image produced by the build is an aggregation of many components, each of which keeps its own license (the Linux kernel is GPL-2.0, BusyBox is GPL-2.0, and so on).

The Mentalnet logo (logos/mnlogo.jpg) is part of this project and licensed under GPL-3.0-or-later with the rest of it.