Comment by yodsanklai

My understanding is that Meta/Google had to rewrite tons of stuff (distributed file systems, CVS, search tools, build tools...) and need many teams to maintain all these systems, and sometime their developer experience is inferior to what you get with off-the-shelf OSS. I'm not super familiar with this topic as I don't work with systems of that scale, but I'm wondering was it worth it or necessary? what would be the alternative?