about the cover illustration
The figure on the cover of Building User-Friendly DSLs is captioned “Marchand Juif à Constantinople,” or “a Jewish tradesman in the city now known as Istanbul.” He is holding a couple of bolts—rolls of fabric—woven on a loom. The fabric shows figures or patterns introduced by the weaving.
Even though this person predates the advent of computers by centuries, textile weaving and DSLs are connected through the Jacquard loom (or machine).1 The Jacquard machine can be thought of as a rudimentary computer executing “programs” that are fed to it in the form of punch cards. The language that those “programs” are written in is far from general-purpose: it’s rather closer to a domain-specific language. The connection between textiles and DSLs doesn’t stop there: knitting patterns are typically described using a DSL.
The cover image is taken from a collection by Jacques Grasset de Saint-Sauveur, published in 1797. Each illustration is finely drawn and colored by hand. In those days, it was easy to identify where people lived and what their trade or station in life was just by their dress. Manning celebrates the inventiveness and initiative of the computer business with book covers based on the rich diversity of regional culture centuries ago, brought back to life by pictures from collections such as this one.