[horizion2025]

I have also had to work with this in many contexts... Deeply embedded systems with no parsers available and where no "proper" ones would fit. So i have hand written but basic parsing and generation a few times.

Oh and there is also non compliant implementations. E.g. some passports (yes the passports with chip use tons of ASN.1) even have incorrect including of big integers (supposed to be the minimum two complement, as I recall some passports used a fixed non-complement format yanked into the 0x02 INTEGER type... Some libraries have special non-compliant parsing modes to deal with it).