code: func sanitizeName(backend string) string {
  	sanitizer := func(r rune) rune {
  		switch r {
  		case '!', '#', '$', '%', '&', '\'', '*', '+', '-', '.', '^', '`', '|', '~':
  			return r
  		}
  
  		switch {
  		case 'a' <= r && r <= 'z':
  			fallthrough
  		case 'A' <= r && r <= 'Z':
  			fallthrough
  		case '0' <= r && r <= '9':
  			return r
  		default:
  			return '_'
  		}
  	}
  
  	return strings.Map(sanitizer, backend)
  }
docs: // sanitizeName According to [RFC 2616](https://www.ietf.org/rfc/rfc2616.txt) section 2.2