After PATH Act was introduced in 2015, the R&D tax credit became permanent and available for startups and small companies with $250,000 maximum amount to claim. Software development is eligible as long as it passes the Four Part Test (systematically resolved technical uncertainty).
You will need technical documentation and employee time-sheets to substantiate the R&D tax credit
claim. Otherwise you risk to not be able to defend your claim in case of an audit.
Unfortunately, most CPAs are not qualified enough to determine eligibility. There are R&D tax credit advisors that specialize in this area and collaborate with business owners and accountants.