I'm not sure where is the line between extensive and basic knowledge. Here is my more detailed exposure:
In commercial context:
* Of strongly typed ones only Scala (with [shapeless]). Can reluctantly throw in Kotlin as well for it's amazing structured concurrency.
In non-commercial context:
* Went through a few chapters of [Software Foundations] doing Coq proofs.
* Worked through most of the [Types and Programming Languages] (writing typecheckers in Ocaml)
* 3 services in Haskell (1 on Scotty, 2 on Servant). Loved persistent+esqueleto for the ORM layer, disliked Opaleye.
* 2 projects in PureScript (1 with Halogen, 1 with React bindings).
* 1 project in ReasonML (Ocaml).
-
> I am afraid there is no way back for me
I see where you are coming from. In my case I can alternate between "I want all invariants properly expressed and checked" and "I just want to ship that barely-working piece of junk and iterate on it". I learned to adjust depending on organization needs. IMO, for many orgs, especially startups/scaleups, the latter is often the more fitting way. With that in mind, I'm willing to trade the guiding hand of great type systems for other productivity aspects (amazing runtime and cohesive web framework in Elixir's case).
In commercial context:
* Of strongly typed ones only Scala (with [shapeless]). Can reluctantly throw in Kotlin as well for it's amazing structured concurrency.
In non-commercial context:
* Went through a few chapters of [Software Foundations] doing Coq proofs.
* Worked through most of the [Types and Programming Languages] (writing typecheckers in Ocaml)
* 3 services in Haskell (1 on Scotty, 2 on Servant). Loved persistent+esqueleto for the ORM layer, disliked Opaleye.
* 2 projects in PureScript (1 with Halogen, 1 with React bindings).
* 1 project in ReasonML (Ocaml).
-
> I am afraid there is no way back for me
I see where you are coming from. In my case I can alternate between "I want all invariants properly expressed and checked" and "I just want to ship that barely-working piece of junk and iterate on it". I learned to adjust depending on organization needs. IMO, for many orgs, especially startups/scaleups, the latter is often the more fitting way. With that in mind, I'm willing to trade the guiding hand of great type systems for other productivity aspects (amazing runtime and cohesive web framework in Elixir's case).
[shapeless]: https://github.com/milessabin/shapeless
[Software Foundations]: https://softwarefoundations.cis.upenn.edu/
[Types and Programming Languages]: https://www.cis.upenn.edu/~bcpierce/tapl/