One more example the early spaceflight guidance computers were completely designed / engineered on paper in graph form, with mathematicians and engineers doing

One more example the early spaceflight guidance computers were completely designed / engineered on paper in graph form, with mathematicians and engineers doing all the hard math work. Assembly programmers would then turn the graphs into assembly using the best technique at the time, at moments having to use NOPs to cool down the ram. For these people the source of truth was the graphs and the actual assembly was throwaway.