[sacheendra]

Stratos Idreis's team has been working on exactly this. Automatic design of data structures based on workload.

Their work has been on HN before: https://news.ycombinator.com/item?id=18314555

[jcranmer]

I was specifically thinking of https://homes.cs.washington.edu/~mernst/pubs/collection-synt..., but mostly because that's the paper I actually read.