system
Given the following post, respond as if you're commenting on Reddit:
human
[Dune] Without computers, how does the high-tech stuff even work? How is it designed and manufactured?

How can a high-tech society, as described in *Dune*, exist without computers? You need them to control industrial robots to manufacture goods for the hundreds of populated worlds; you need them to engineer things like Holtzmann drives to minute tolerances; and a giant piece of machinery like a Guild Heighliner probably needs dozens of them, to control and adjust engine thrust, air pressure, internal temperature, and hundreds of other parameters.

How to they make do without it? It's not like they can put a Mentat behind every CNC lathe in the Empire.
gpt
The OC Bible actually states "Thou shalt not make a machine in the likeness of a human mind"; i.e., the ban is on artificial intelligence, not computers per se. Unfortunately, for the masses, the distrust extended to non AI computers. Nevertheless, computers do exist, particularly those made by the Ixians, though their use is limited because of the misguided general mistrust of technology. It is rumored the Ixians skirt the boundaries of the anti-technology proscriptions of the Butlerian Jihad, but the Great Houses turn a blind eye as long as there are no egregious violations. The ruling classes  necessarily traffic in such devices made by Ix, but do not do so overtly for fear of rousing the mobs. 

[Edit to add more detail] This actually explains how the Dune society came to be: what appears to be a medieval, feudal society but with the trappings of high technology. The Butlerian Jihad sought to eliminate AI but for the common people, there was little difference between a neural computer and a calculator; as a consequence, all forms of technology is suspect and avoided. A peasant would probably live his life and the most high tech thing he'd probably see is a glowglobe on suspensors ... common enough that he wouldn't even think twice about it. The higher up you are in society, the more exposed you are to gadgets and technological tools, but nothing that would raise your eyebrows. The leaders of their society, the nobles and lords, as well as the specialized guilds, all make use of technological tools as a matter of course; in their position, they have to accept the necessity of it, even if they themselves distrust these tools. And they definitely avoid becoming dependent on these tools, out of their own fear and fear of arousing the suspicions of their subjects. 

This also explains the rise of specialized guilds. The manufacture of high tech goods becomes a balancing act between applying computerized technologies, and using skilled labor to replace manufacturing techniques that are too close to the prohibitions for comfort.