1. In this sentence, "scaffold" is being used as a verb (actually like a phrasal verb with 'out'). In general terms, a scaffold (noun) is a temporary structure used by construction workers and painters to reach tall parts of a building in order to do their work. (Notre Dame Cathedral had such a structure outside it before it caught fire.) I'm not an IT expert, so without more context, it's difficult to say exactly what the writer meant here. 2. I believe the use of "Pilgrim" is a nod to the late actor, John Wayne. It's one of his most famous pet names for people in his cowboy movies. https://www.youtube.com/watch?v=9O8oLqY2sxo In more general terms, 'pilgrim' has two meanings: http://learnersdictionary.com/definition/pilgrim