Hi 
I’m Ryan, and I’m a Backend Engineer here at Monzo.
This blog tells the story of how Monzo became a Direct Participant of the Bacs payment scheme, and what this means. Receiving your salary and paying Direct Debits are crucial parts of banking, and our customers expect them to just work. We had to perform a series of changes to how we receive these payments and how money moves between us and other banks, all without affecting a single one!
I hope you find it interesting!
there are still tape markers in the digital files we receive today!
Already very interesting from the first couple of paragraphs!
Thanks - really interesting blog post.
It would be great to get an update on any progress that has been made on supporting receipt of international payments into Monzo accounts. Does this work have any impact on readiness for that?
The talk of these files being transferred, makes me wonder if it’s just a secured FTP server or is it something more complicated? Would love to know (if it’s allowed to be public knowledge)
No direct answer I can find on that, but if FTP is still used deep down it is secured by the wider technology of “Bacstel-IP”, like hardware security modules and the like
Here are a few bits from a brief dig:
Only software solutions that have passed a number of rigorous testing and approval processes are enabled to connect to Bacstel-IP for the Bacs Payment System and / or Secure-IP for the Faster Payment System.
https://www.bacs.co.uk/services/bacs-schemes/getting-started/direct-submitters/
Bacstel-IP is the delivery channel which gives corporate users secure online access to Bacs. Bacstel-IP is a multi-layered, highly advanced, online submission channel and the largest Public Key Infrastructure (PKI) community in the world.
Bacstel-IP is an online submission channel which is safe and resistant to data tampering. Direct submitters use the service to submit their payment files to Bacs. They can also track payments and view payment reports using the service.