@connection_with_reality @Endof10 I boot up Windoze in a VM to run Tax software. I don't know how to convince TurboTax/TaxAct/HRBlock/etc to have a Linux release. Maybe as a container release? There are legit reasons it is not open source.
An open source engine + proprietary tax rules database might work, but the rules are complex enough to be Turing complete.
The best solution is Flat Tax or Sale Tax and dispense with tax software altogether.