Brian Wilson from Backblaze here (not the "Brian Beach" who is author of the blog post) - this was not a case of NIH. We use lots and lots and lots of existing software like Debian, Java, Ext4. We use tools like ansible and Zabbix. But this one thing just didn't exist for us in the form we needed it. We looked, we really did.

We did write the Reed-Solomon ourselves in a "clean room" so we did not have to pay any licensing fees and we clearly didn't steal anybody else's source code, but that is a very small amount of code. Like 80 lines of Java. Seriously. We referenced the technical papers we read to implement it in that blog post, but here it is again: http://www.cs.cmu.edu/~guyb/realworld/reedsolomon/reed_solom... And we unit tested the living heck out of that code, plus we mathematically verified various parts.

But I'm open to an alternative solution if you can suggest one? Remember our three highest priorities are: 1) reliable, 2) low cost, 3) simple. The "low cost" includes things like we do not want to pay ongoing licensing fees to other companies.