[amomchilov]

The unrefactorable ball of mud problem is real, which is why both Stripe and Shopify have highly statically typed code bases (via Sorbet).

Btw Stripe uses Ruby, but not Rails.

[byroot]

I'd say sorbet largely adds to the mud, but to each their own.

[m00x]

Some Stripe services are Rails.

Having types helps, but it's not a necessity. When I was at Chime we faired very well with just rails and no types.