An interesting case study — adding email-based ROS middleware (RMW):
Here’s something like a call for proposals for an alternative, non-DDS-based RMW, where someone has brought up Cyphal already; the list of non-DDS-based RMW implementations provided in the post is interesting to look at:
By looking at the source code of the existing non-DDS RMW, I see that the effort required is actually lower than I anticipated.