Native settings written to the notmuch configuration file. Lists are serialized as semicolon-separated values, including empty lists. Null settings and empty sections are omitted. Unset keys use notmuch's own defaults. database.path defaults to accounts.email.maildirBasePath when an email account is enabled, and notmuch-enabled email accounts supply user values; any definition of the same key replaces these. For home.stateVersion below 26.11, database.path has this default even without email accounts, and search.exclude_tags defaults to deleted;spam. new.ignore, new.tags, maildir.synchronizeFlags, search.excludeTags, and extraConfig under programs.notmuch are deprecated aliases into settings. Alias definitions retain their priorities and list ordering. Definitions of the same list setting concatenate unless a stronger priority replaces them. Unlike the old final extraConfig overlay, conflicting ordinary scalar definitions must be resolved in settings. Apply lib.mkDefault to individual settings, not to a whole section or the whole attribute set; section-level priorities lose to definitions Home Manager or the mbsync, lieer, and mujmap modules supply in database, new, search, and user.
See https://notmuchmail.org/manpages/notmuch-config-1/ for available settings.