Package config provides typesafe, cloud native configuration binding from environment variables or files to structs. Configuration can be done in as little as two lines: A field's type determines what https://golang.org/pkg/strconv/ function is called. All string conversion rules are as defined in the https://golang.org/pkg/strconv/ package. If chaining multiple data sources, data sets are merged. Later values override previous values. Unset values remain as their native zero value: https://tour.golang.org/basics/12. Env vars map to struct fields case insensitively. NOTE: Also true when using struct tags.