"For all you founders, CTOs, and developers out there, remember that either your code is FOSS, or you’re asking for your users’ trust. Either your code is free, or you’re running a bank, not a bitcoin company."

If it's not FOSS, it's not Bitcoin.

https://medium.com/breez-technology/if-its-not-foss-it-s-not-bitcoin-9a6bc53182e5