DeepfakeHTTP – Your 100% static dynamic back end
github.com
github.com
And in classic HN retort, the time it would take just hand crafting all these responses you could spin up some SQLite to REST, or whatever database floats your boat.
At one point I was trying to automate against an internal tool that had a (useless, for my purposes) dependency on AWS. Rather than give my pipeline access to AWS, I strapped VCR (https://github.com/vcr/vcr) onto it, ran it on my laptop with my own AWS permissions, and then just ran the automation with VCR in front of it from there on out.