The smallest piece of great Pharo code https://medium.com/concerning-pharo/tiny-yet-so-beautiful-1ef5149c910e (explores adding methods to built-in classes and idiomatic Smalltalk design)
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Which languages do you consider to have the biggest/smallest standard libraries?
JS and Rust have a reputation for being pretty small. C has fewer data structures, but a bunch of system APIs.
Python feels more like a kitchen sink.
Where are other languages on this spectrum?
Making smallest possible test suite using Z3
https://yurichev.com/blog/set_cover/
(really elegant application of the set cover problem to test suites)