“Given our very aggressive growth rate, we had only months of runway remaining.”
Figma’s database stack grew almost 100x since 2020, starting from one Postgres box on AWS’s largest instance. Its hottest tables were about to blow past RDS’s IOPS ceiling with months to spare. It looked at CockroachDB, TiDB, Spanner and Vitess and built its own sharding proxy on RDS instead, without atomic cross-shard transactions. That is not a principled architecture choice. It is what happens when the migration you put off has to ship before the ceiling arrives.