[maximente]

viper, which nicely handles env vars, also can watch for config changes: https://github.com/spf13/viper#watching-and-re-reading-confi...

if you're rotating creds or need to open/close the DB, this will typically just add another select case to your main method, where you also block on e.g. signal catching to cleanly shutdown the app

[snupples]

Be aware that viper isn't thread safe. You'd still have to copy config by value and then put a mutex on that, then handle reads and writes separately.

https://github.com/spf13/viper#is-it-safe-to-concurrently-re...