[viraptor]

I'm curious - I've never seen tech books that short that people actually buy. Could you link some example?

The closest I know of are the Julia Evans' zines, but I think you meant something different.

[coldtea]

>I'm curious - I've never seen tech books that short that people actually buy.

Not sure about 20 pages or so, but there's a whole variety of short tech books. O'Reilly had their "pocket reference" series, some of which are less than 100 pages.

[jensv]

Here's an example on GTFS. https://gumroad.com/l/gtfsbundle