Note: I haven't used Net::Etcd or etcd before, so just speculating.

I have a feeling you won't be able to do that using the Perl module. From what I can see from the docs for range_end, plus this clarification of what it means (their examples of "aa"+1 == "ab", "a\xff"+1 == "b"), plus how it's implemented in Perl by calling encode_base64 on whatever you pass in; assuming it's that encoded data that's passed to the underlying go code, it seems like you won't ever be able to "increment by 1", since the encoded thing will be..."randomized".

But maybe I'm misreading things..

EDIT: thinking about it more, probably the encoding/decoding is just to pass it over JSON, so the encoding part was wrong. So maybe if you can figure out how to translate "a\xff"+1 == "b" to Perl. I'm not sure exactly what that means, but it seems to take the bit representation of the string and add 1 to it? (Am I just repeating your original question? Heh...)