Perl has various levels of bolted-on type-strictness too AFAIK, I don't have much experience with it due to being stuck on an older version professionally. I p

Perl has various levels of bolted-on type-strictness too AFAIK, I don't have much experience with it due to being stuck on an older version professionally. I personally think it's a great idea. Loose types can get a POC or even early production models up and running quickly while you're changing your opinions on the data every hour, then once it grows to a size that's hard to reason about and static analysis can really pay off, start tightening it up.