Not So Fast, Slick
Why Did it Take Devuan Two Years to Replace Systemd?
Copyright © 2017 by Steve Litt
Recently, a guy asked me two questions:
Here's my answer:
Imagine having a bicycle with hand brakes. You know, the kind of brakes with brake pads that rub against the wheel rims. You can get black brake pads, salmon color brake pads, short brake pads, long brake pads, smooth stud brake pads, threaded stud brake pads, whatever. The point is, to change to a different color or length or pad composition is trivial: Take the old ones off, put the new ones back on.
But your bike has the new Lennart Poettering "systemd" brake design, with its new metalic brake pads, which stop the bike nicely, but wear out the wheel rims in 300 miles.
To protect your rims, you decide to switch brakepads.
Not so fast, Slick. Instead of having its brake pads simply bolt onto the brakes, systemd brake pads have two clips, three notches, four micro-bolts with special screw heads, and something resembling an FM2 processor socket, all of which must mesh to the systemd brake to attach it. Systemd brake pads are the only ones with this interface, all systemd brake pads are metallic, and from a manufacturing viewpoint it's economically impossible to equip this brakepad interface with non-metalic pads.
You say to yourself: "Fine, I'll just replace the systemd brakes with regular brakes."
Not so fast, Slick. The systemd brakes have a hydraulic line to the crank, which when you press the brakes throw the bike into neutral. Of course, this requires the systemd crank to be on the bike. So if you replace the brakes, you need to replace the crank also, or else freelance a permanent high pressure hydraulic defeat of the crank, and nobody's made that yet because the systemd crank actively tests for such a defeat.
So fine, you'll replace the crank too.
Not so fast, Slick. The crank must have an unusual sized chain. More challenging, the crank feeds hydraulically into the special systemd derailleurs (systemd automatic transmission), and these derailleurs cannot be jimmied to take their shifting information from regular shift levels and cables, nor even from rigged hydraulic ones, because the systemd hydraulic brakes detect a pressure frequency modulation that only a systemd crank can deliver.
No problem, you'll replace the derailleurs.
Not so fast, Slick. Systemd derailleurs are mounted on the frame and fork in a place where normal frames and forks have no presence. Brazing on accouterments to mount systemd brakes to a normal frame is tricky at best, and usually not safe.
You're a problem solver, so you'll just replace the frame.
Not so fast, Slick. Systemd frames require special systemd wheels that have axles a foot wide. Bending a systemd frame to accommodate a normal wheel renders the frame brittle, and using hardware to do the job puts excess torques on the systemd frame and fork.
OK, you'll play their silly game. You'll replace the wheels.
Not so fast, Slick. The systemd wheel hubs have special hydraulic connections to the monolithic seat and seat-post assembly, as a theft deterrent.
Now you've got these guys on the run. You replace the monolithic seat/seat-post assembly with a normal seat and seat-post.
Congrats, you've installed non-systemd brake pads on a systemd equipped bike. It took two years, but it's worth it.
Of course, you had to replace the brake pads, brakes, crank, derailleurs, frame and fork, wheels, monolithic seat and seat-post. Every part of the bike. The cheapest way to get all those parts is just to buy a new bike. Fortunately, there are bike brands like Devuan, Void, Alpine, Funtoo, OpenBSD and FreeBSD that have no systemd parts.