BcalcOS is built on Devuan, which means it takes a different approach to one of the central pieces of a modern Linux system: the use of systemd.
This choice comes with practical consequences.
What systemd does
Systemd began as an init system (the first user-space process started by the Linux kernel) but it has grown into a much broader collection of system and service-management components. Among other things, systemd can start and supervise services, manage mounts and devices, provide logging through journald, coordinate user sessions, and provide interfaces used by other software.
Because systemd has become such an ubiquitous part of the Linux ecosystem, some software now assumes that systemd or one of its interfaces is available.
What happens without it?
A Linux system requires basic capabilities such as an init system, service management, logging, device management, networking, and other system services. The difference with Devuan, and with non-systemd distributions in general, is that these functions are provided by different components rather than being built around systemd and its collection of associated services and interfaces.
A resulting trade-off is that there can be more variation between Linux distributions.
A program that works on a systemd-based distribution may:
- not be available in exactly the same form on Devuan or BcalcOS
- have different dependencies
- require a different service-management method
- expect systemd-specific interfaces that are not present
- require additional work from distribution maintainers
Devuan’s documentation describes the work involved in removing systemd dependencies from packages. Not all software, however, can readily be de-systemdnized.
Why use a system without systemd?
Some users prefer keeping the init system separate from the multiple other functions that have accumulated around systemd. (Do one thing and do it well). Devuan exists in part to preserve that choice; allow users to build a Debian-compatible system around alternative init systems.
BcalcOS follows this because we believe that simpler software is usually, no not always but usually, a better approach.
What this means for BcalcOS
We recognize that the typical Linux user does not want to become an expert in the differences between systemd and the alternatives.
That is one reason we add an integration layer on top of Devuan. The installer, curated repositories, Welcome Center, maintenance tools, desktop configuration, and BcalcOS applications are intended to make the underlying system feel like a complete desktop rather than a collection of components that the user must assemble themselves.
That said, there can be real technical limits. Some software is developed primarily with systemd-based distributions in mind so there may occasionally be packages that simply do not translate directly to BcalcOS.
The goal, though, is to make the init question matter as little as possible to the average Linux user.