The official solutions, node-ffi and node-ffi-napi, are extremely slow, with an overhead hundred of times higher than it should be. I don't know what they do to be so slow.

I'm making my own FFI module for Node.js, Koffi, as a much faster alternative. You can see some benchmark here, to compare with node-ffi-napi: https://www.npmjs.com/package/koffi#benchmarks