➜  crystal git:(master) ls
lib  LICENSE  README.md  shard.lock  shard.yml  spec  src
➜  crystal git:(master) crystal run src/Crystallizer.cr
while requiring "ENV" (Exception)
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Caused by: can't find file 'ENV'

If you're trying to require a shard:
- Did you remember to run `shards install`?
- Did you make sure you're running the compiler in the same directory as your shard.yml? (Crystal::CrystalPath::Error)
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