Business owners generally cannot count their own time spent on their business as a business expense. Software here is no different than a restaurant owner trying to write off the time it takes him/her to develop a menu, negotiate with suppliers, or manage employees: not allowed. It's assumed that as a business owner, spending your time on the business is what you do, much like as an employee, spending your time on your job is what you do; an employee cannot write off "time spent on my job" from their taxes, and you can't write off "time spent on my business".

One possibility, however, is to pay yourself a salary. Then from the business side, you could write off the salary as a business expense. But now you will pay personal income taxes on the salary. Also, you cannot do this if you're a sole proprietor, and even if you're incorporated, should probably consult with an accountant and/or lawyer to make sure it's legit in your case.