In-flight business objects for major airlines is probably considered scale: https://www.couchbase.com/customers/united-airlines
Cloudant (API Compatible with CouchDB) has a number of case studies you can reference for production success with the Couch API/ecosystem.
Cabify - https://www.ibm.com/case-studies/cabify-cloudant
Ticket Fairy - https://www.ibm.com/case-studies/the-ticket-fairy-cloud-clou...
We.Trade - https://www.ibm.com/case-studies/wetrade-blockchain-fintech-...
Disclaimer: I work for IBM Cloud