How to make Flowtype work on CircleCI v2.0?

From this failed build:

$ ./node_modules/.bin/flow
Shell: /bin/bash -eo pipefail

/root/bertha-client/node_modules/flow-bin/flow-linux64-v0.42.0/flow: error while loading shared libraries: libelf.so.1: cannot open shared object file: No such file or directory
Exited with code 127

It seems that Flow is failing because it can’t open something called libelf.so.1. I’m guessing this is something to do with running on Docker instead of a real machine, but I’m very new to Docker so I don’t know what to do. Can anyone help?