What's a good adverb to indicate an attribute that cannot be improved upon?
I wanted 'untoppably' to be a word, but it isn't.
Optimally and its synonyms come to mind, but it doesn't really have the best fit for the phrase I have in mind:
I’ve thought up a pretty neat method for completely eliminating dynamic cell references. I wrote it down for later. You can look forward to an [untoppably] fast version whenever I get a free week to implement it. (Could be a month, could be a year)

