"After experiencing the kinds of bugs I described above, it became clear to me that – despite their merits – immutable data structures are not a silver bullet."

"After experiencing the kinds of bugs I described above, it became clear to me that – despite their merits – immutable data structures are not a silver bullet." There ARE NO silver bullets. So many developers want them, but they don't exist. It's a gigantic form of laziness that causes so many problems in software teams, and people drowning in it can't see it, or refuse to. Good developers that see tools in a toolbox instead of constantly searching for silver bullets are rare and should be retained at great cost.