I read this comment:

You could consider running a pruning node, which is practically the same as a full node (including security), except it throws away some of the old history. Version 0.11 will make that possible

But I can't find details of how to run bitcoind in pruning mode. Questions on this site seem not to be recent enough to yield answers, and I also don't see a pruning mode in the bitcoind parameters.

Any insights into this?