Article 6 of 6
Why BcalcOS Uses SLiM
So, why does BcalcOS use a twenty plus year old display manager?
Not every distribution should. Different distributions have different priorities.
Simplicity Matters
One of the principles behind BcalcOS is that a computer operating system shouldn’t be unnecessarily complicated.
SLiM has a relatively simple role: present a login screen, authenticate the user, and start the session. Its main configuration lives in one file and it doesn’t try to manage the desktop itself.
Complexity should have a reason and BcalcOS doesn’t want to add more here than the job requires. User switching, GUI configurations, or a flashier greeter screen aren’t mission critical.
It’s Understandable
Want to see how SLiM is started?
Look at: /etc/init.d/slim
Want to see how it’s configured?
Look at: /etc/slim.conf
Want to see which sessions are available?
Look at: /usr/share/xsessions
Want to know what happened at the last login?
Look at: /var/log/slim.log
The system isn’t hiding these mechanisms from you.
That fits an important BcalcOS philosophy:
Users should be able to determine what their computers are doing.
A Consideration of Maintenance
The original SLiM project was long regarded as inactive and some online documentation still carries warnings about it. The fuller picture is more nuanced: a revived SLiM fork has appeared in some distributions and Devuan has shipped fixes for SLiM bugs in recent releases.
Upstream project activity and distribution package maintenance are related but they aren’t the same thing. A distribution may carry fixes even when the original project has been quiet.
There may come a time when BcalcOS needs to move away from SLiM. Not because it stopped fitting the distribution’s design, but because its maintenance status, security updates, or compatibility with newer software make another display manager the more responsible choice.
Preferring simplicity doesn’t mean holding on to a component past the point where it’s a sound choice. LightDM would be an obvious candidate except someone beat us to it.
There’s no expectation that BcalcOS will replace SLiM anytime soon. It’s just an acknowledgment that forces outside our control may prompt a change.
The Whole Picture
The graphical experience of BcalcOS is the sum of separate, understandable pieces:
SysVinit
↓
SLiM ── starts ──→ XLibre
│
└── successful login → Xfce session
Each has its own job. Each can be inspected. Each can be understood.
The point of this series was to highlight a basic yet essential component of BcalcOS. To pull back the curtain just a bit.
After all, it’s your personal computer.