Set the `permanent` option to `true` to apply a permanent redirection.
### regex
The `Regex` option is the regular expression to match and capture elements form the request URL.
!!! warning
Care should be taken when defining replacement expand variables: `$1x` is equivalent to `${1x}`, not `${1}x` (see [Regexp.Expand](https://golang.org/pkg/regexp/#Regexp.Expand)), so use `${1}` syntax.
!!! tip
Regular expressions and replacements can be tested using online tools such as [Go Playground](https://play.golang.org/p/mWU9p-wk2ru) or the [Regex101](https://regex101.com/r/58sIgx/2).
### replacement
The `replacement` option defines how to modify the URl to have the new target URL.