As you know if you've been following this blog, at Igalia we build network functions using the Snabb toolkit. When we're not directly working on customer projects, we often invest time into building new features into Snabb.
One of these recent investments has been building a basic IP flow export (IPFIX) app for Snabb. The app is now available in the v2017.08 Snabb release. The app's documentation is up on the web here.