Hi @indrajit, Really sorry that no one from the team reached out to you with a response. We will try to be better with our efforts in the future.
Now to your question, We are really happy that you are satisfied with the performance of Ristretto. Ristretto is being actively used by Badger(underlying database of Dgraph) and many of our customers are using it in production. So feel free to use ristretto for your production use cases. We at Dgraph are committed to change the landscape of Graph databases, and that means we will continuously work on improving the performance of ristretto. So I will advise you to keep an eye out on new releases.
Do let us know if you face any issues. And keep your questions coming 
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