I was standing at the bench with loupe in hand looking at a cutter edge when out of the corner of my eye I saw a black snake about a meter long slither out from under the bench heading for a corner of the shop where stuff was stored. Once over the startle effect I googled "black snake Arizona" and came up with a Black Kingsnake. It is rare and only found in the States along the Mexico border. They are harmless, other than heart attacks, and live on other snakes, mice, and rats.
Bottom line, as long as he/she doesn't crawl up my leg the snake has a home for as long as he/she wants it.