The Story

Pulling the thorn from the lions paw

H&R brought us in because they had a very expensive problem on their hands. Their software from the previous year had submitted a small percent of their state filings with incorrect formatting. These formatting issues were very small and very easily overlooked by anyone, however, with the volume of tax returns that H&R Block files, even the small percent of errors were overwhelming the states and caused the states to start blocking all filings from H&R Block. They estimated that if the bugs would have affected more states and if they had been harder to fix, they could have lost the company a billion dollars.

The Challenges

Due to the nature of State tax collections services, running large scale tests against their systems before tax day wasn’t always an option. All tax software providers were expected to develop against a paper specificication of the filing format. It was an inheretly error-prone process and not something that H&R Block had control over, so they needed another solution.

The Solution

We started by searching the entire code base to find all the segments of code that had the potential to cause similar problems to the ones that had caused the previous years problems. We changed those segments of code to be more explicit and more easily to fix quickly if needed. Then we worked with the internal development team to emphasize which sections of code had potentially disasterous affects for the company so they could know which sections of code to be extra diligent on. We decided, however, that it wasn’t reasonable to expect the developers to never make mistakes, so we also created tools that would help fix a large number of “same type” errors across the whole code-base if it was needed.

H&R Block felt that their risk has been sufficiently mitigated and to my knowledge they haven’t had any issues with states blocking all of their filings since.