Pigeonhole Sieve Plugins
The Pigeonhole Sieve interpreter can be dynamically extended with new features by means of plugins. Plugins can be configured using the sieve_plugins setting in the plugin section of the Dovecot configuration, as explained on the Pigeonhole Sieve Configuration page.
The following plugins are currently available for the Pigeonhole Sieve interpeter:
Extdata (custom language extension, experimental)
This plugin adds support for the Dovecot-specific vnd.dovecot.extdata extension, which allows access to external string data. Any type of Dovecot dict lookup can be specified as data source.
Pipe (custom language extension, experimental)
This plugin adds support for the Dovecot-specific vnd.dovecot.pipe extension, which allows piping messages to a pre-defined set of external programs.