Thanks for the feedback and pointing out ostiary. Fixing replay attacks is on my todo list, maybe I can learn some things from how ostiary does it.

Kind advice from my PoV:

Your comment could be read as "your project is shit, there is ostiary which has replay protection and yours doesn't".

I'm sure you didn't intend for you comment to not come across that way, and I also did not read it that way, but others could have.

Also keep in mind that ruroco is a very young project and is by no means finished. I was thinking about using one-time-pads or other encryption algorithms as well. I also posted this here to get feedback to improve my project.

So hopefully when I release version 1.0.0 all the issues that this project has atpit are resolved ;)