A lovely example of extensible type systems evolving independently from the underlying language!
miniblog.
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On thinking of books like software, treating them as evolving artifacts, and URLs versus paper book publishers:
Internet software decays: https://utcc.utoronto.ca/~cks/space/blog/tech/InternetSoftwareDecay
(Software is dependent on the environment, and that's changing! You also have to stay on top of evolving security concerns.)
Great overview of how Haskell has evolved in 2017: https://www.stephendiehl.com/posts/haskell_2018.html
Includes some interesting comments about the future, e.g. the community gravitates towards pluggable extensions rather than evolving the base language.