(1) the "where name = ..." isn't doing anything here

(2) You're missing the target rectangle for the scratchpad (whether to make a tiled window, a standard floating window, or a custom floating window). That's the source of the type error. Compare to my earlier pastebinned example:

myScratchpads = [NS "calendar"
                    "xterm -title calendar -hold -e task calendar"
                    (title =? "calendar")
                    -- I don't know screen or font size so this is a very rough guess at the RationalRect
                    (customFloating $ W.RationalRect 0 (1/10) (4/10) (3/10))
                ]

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