BcalcOS is built on Devuan GNU+Linux.
Devuan is a Linux distribution derived from Debian but with a different approach to system initialization and system management. Devuan’s primary goal is to provide a Debian-based operating system without systemd as its required init system, giving users and distributions greater choice over how the system is initialized and managed.
Why Devuan for BcalcOS?
BcalcOS uses SysVinit rather than systemd. Devuan provides the foundation that makes this possible while retaining the familiar Debian package ecosystem and apt package management.
This gives BcalcOS a traditional Unix/Linux system architecture while still benefiting from the large body of software, packaging, documentation, and hardware support that has developed around Debian and its derivatives.
What Does Devuan Provide?
Devuan provides much of the underlying operating system, including
- the Linux kernel and core system components
- system libraries and utilities
- the
aptanddpkgpackage-management system - a large collection of available software packages
- hardware and device-management components
- security and system updates
Devuan currently bases its stable Excalibur release on Debian 13.
What Does BcalcOS Add?
BcalcOS adds its own choices and components, including the custom installer, BcalcOS configuration and branding, custom applications, the Welcome Center, selected third-party software, Brave Origin as the default browser, and XLibre as the X11 display server.
The Relationship
Debian → Devuan → BcalcOS
Devuan provides the operating-system foundation which, frankly, is of more effort than BcalcOS.
BcalcOS builds on that foundation and adds its own software, configuration, installer, desktop choices, and user experience.
The Short Version
BcalcOS is built on Devuan because we want a Debian-based Linux foundation with SysVinit and the freedom to make our own system-level choices.