[shkkmo]

I used their system to submit my taxes this year. (Edit: the "free fillable forms" system)

Their UX is absolutely atrocious. It will do the math for you, but there are a number of intermediate fields that require you to enter a value manually, but have no indication in the form of what they are. You have to go through their instructions (separate from the IRS instructions) for the form to figure out what fields require manual entry.

Eventually I was able to work my way through the form with research and experimentation.

The only thing I wasn't able to figure out was how to get it to include the penalty for failing to pay estimated taxes. I added the form to my filing and filled it out, but I could never get the number of populate into the 1040 and their form wouldn't let me enter that value manually. While I would have preferred to pay it all at once, my only option was to wait for the IRS to calculate this and bill me for it.

Can we please, please, please get 18F to rebuild this so it doesn't completely suck? Offering a solid, free alternative to Turbo Tax and other abusive companies would be so beneficial.