I was lucky enough to receive the Revolut Business API first thanks to @JamesRevolut - I understand the API will be rolled out to the wider group in the coming month. He recently asked if I could share what I built. I wrote a small Laravel app that passes transactions into a Slack channel (http://share.agnew.co/qswXmO ) and any completed transactions go into Freeagent.
You can find the code on Github: https://github.com/jasonagnew/revolut-business-transactions
I don’t really have time to offer support (plus the code base is messy as I wrote it in 2 hours for myself) so its aimed at helping others developers.
We’ve used this since the 30th October without any issues.