8.1.3.1 Associating Engines

When searching a group, nnir needs to know which search engine to use. You can configure a given server to use a particular engine by setting the server variable nnir-search-engine to the engine name. For example to use the namazu engine to search the server named home you can use

(setq gnus-secondary-select-methods
      '((nnml "home"
         (nnimap-address "localhost")
         (nnir-search-engine namazu))))

Alternatively you might want to use a particular engine for all servers with a given backend. For example, you might want to use the imap engine for all servers using the nnimap backend. In this case you can customize the variable nnir-method-default-engines. This is an alist of pairs of the form (backend . engine). By default this variable is set to use the imap engine for all servers using the nnimap backend, and the gmane backend for nntp servers. (Don’t worry, the gmane search engine won’t actually try to search non-gmane nntp servers.) But if you wanted to use namazu for all your servers with an nnimap backend you could change this to

'((nnimap . namazu)
  (nntp . gmane))