It's an async/await framework for C++. I'm not sure what the best source on this is, but here's a discussion: https://forums.foundationdb.org/t/why-was-flow-dev

It's an async/await framework for C++. I'm not sure what the best source on this is, but here's a discussion: https://forums.foundationdb.org/t/why-was-flow-developed/1711/3 https://forums.foundationdb.org/t/why-was-flow-developed/171... My understanding is that FDB relies heavily on deterministic simulations for testing, and that their async/await model is a big part of how they make sure they cover different possible interleavings in a deterministic way.