I love this too. Moving Pinboard from whatever flavor of PHP it was based on (in 2009) onto 7.3 only ran into two issues—something to do with the "explode" function, and requiring a certain kind of constructor in objects. All the rest of the migration pain involved libraries.

Granted, Pinboard is just a wrapper around some SQL queries, but that's what most PHP apps are. It was a big relief to find the migration so easy.