> Facebook's use of Cassandra and CI lint-checks and blue-green deployments is just like military cargo planes' use of radio towers — they didn't build those fi

> Facebook's use of Cassandra and CI lint-checks and blue-green deployments is just like military cargo planes' use of radio towers — they didn't build those first; they scaled the thing they were doing to the point that these things became necessary support structures, and then they built them. This is so true. In fact, a lot of the technology choices companies at the scale of Facebook use are only necessary because they're so large/popular, and were added later to stop everything falling over. Because it's so unlikely your project will ever need to contend with a billion users or whatever, you really shouldn't be designing under the assumption that's likely to happen.