I think that hand-rolled parsers are good if: 1) You have a team that knows well what they are doing 2) You have a lot of resources 3) Your language is stable

I think that hand-rolled parsers are good if: 1) You have a team that knows well what they are doing 2) You have a lot of resources 3) Your language is stable I would argue that parser-generators are what made those projects to be started and prosper in the first place. Then once one is successful a custom solution could make sense but in my experience it is more expensive and potentially less maintanable, unless you know very welll your way around parsers and language tooling