This (https://github.com/wowsignal-io/go-forex https://github.com/wowsignal-io/go-forex) runs locally* without using a web API, comes with a command line tool a

This (https://github.com/wowsignal-io/go-forex https://github.com/wowsignal-io/go-forex) runs locally* without using a web API, comes with a command line tool and supports 50 currencies without requiring one of them to be the USD. It’s also faster and open source. This is a solved problem. * It caches a local copy of the currency data from some major banks.