Beach ball while editing

[jvdp]

Hi,

When I'm editing a reducer in a reasonably large project I get frequent lockups complete with the infamous OS X beach ball mouse cursor. (These reducers are a bit challenging because there's a big sum-type for all the actions and states.) But shouldn't Flow run in a background process?

My only config is "use_npm_flow": true and I'm using Flow version 0.52 (not upgraded yet, that's why I need to rely on the npm version...)