We do for for managing stuff with many $1... zeros for serious top fortune companies in business critical projects. Java/Go type systems are primitive compared to typescript. Shallow or no dependencies, functional, ocaml like modules, pervasive use of algebraic types provided by ts (previously flow), several years in production, nice codebase, several successful, non-trivial major releases, constant updates with codebase worked on every day by many people, several deployments per month.

Problems I personally have with it:

1. no exact object types in ts as in flow - means they have to be emulated by destructing, sad, but you can live with it/you have to be careful

2. transpile times - but recent experiments with swc for tranpilation and deferring typecheck to run concurrently while tests are kicked off after swc finishes look promising

3. type system could be a bit smarter in few places, but no blockers so far

I'd recommend but with caution - spectrum of developer's competency is closer to php (almost anybody can do it) than the one of languages like ocaml/haskell/rust and others (where entry bar is higher). Vet your dependencies, hire competent developers and it can work very well.

Some of libraries we're using:

- https://github.com/appliedblockchain/assert-combinators - light, runtime type assertions ("parse, don't validate" style to avoid illusion of type safety at io boundaries)

- https://github.com/appliedblockchain/tsql - functional, tagged template based combinators for sql generation