Use the opensmtpd package as it was updated in guix
modules/config/mail.scm
| 112 | 112 | (define (lepiller-smtp-service interface domain) | |
| 113 | 113 | (service opensmtpd-service-type | |
| 114 | 114 | (opensmtpd-configuration | |
| 115 | - | (package opensmtpd-next) | |
| 116 | 115 | (config-file (opensmtpd-conf interface domain))))) | |
| 117 | 116 | ||
| 118 | 117 | (define (lepiller-dkim-service domain) |