+Notmuch 0.18 (2014-05-06)
+=========================
+
+Overview
+--------
+
+This new release includes some enhancements to searching for messages
+by filesystem location (`folder:` and `path:` prefixes under *General*
+below). Saved searches in *Emacs* have also been enhanced to allow
+distinct search orders for each one. Another enhancement to the
+*Emacs* interface is that replies to encrypted messages are now
+encrypted, reducing the risk of unintentional information disclosure.
+The default dump output format has changed to the more robust
+`batch-tag` format. The previously deprecated parsing of single
+message mboxes has been removed. For detailed release notes, see
+below.
+
+General
+-------
+
+The `folder:` search prefix now requires an exact match
+
+ The `folder:` prefix has been changed to search for email messages
+ by the exact, case sensitive maildir or MH folder name. Wildcard
+ matching (`folder:foo*`) is no longer supported. The new behaviour
+ allows for more accurate mail folder based searches, makes it
+ possible to search for messages in the top-level folder, and should
+ lead to less surprising results than the old behaviour. Users are
+ advised to see the `notmuch-search-terms` manual page for details,
+ and review how the change affects their existing `folder:` searches.
+
+There is a new `path:` search prefix.
+
+ The new `path:` search prefix complements the `folder:` prefix. The
+ `path:` prefix searches for email messages that are in particular
+ directories within the mail store, optionally recursively using a
+ special syntax. See the `notmuch-search-terms` manual page for
+ details.
+
+Notmuch database upgrade due to `folder:` and `path:` changes
+
+ The above mentioned changes to the `folder:` prefix and the addition
+ of `path:` prefix require a Notmuch database upgrade. This will be
+ done automatically, without prompting on the next time `notmuch new`
+ is run after the upgrade. The upgrade is not reversible, and the
+ upgraded database will not be readable by older versions of
+ Notmuch. As a safeguard, a database dump will be created in the
+ `.notmuch` directory before upgrading.
+
+Library changes
+---------------
+
+Notmuch database upgrade
+
+ The libnotmuch consumers are reminded to handle database upgrades
+ properly, either by relying on running `notmuch new`, or checking
+ `notmuch_database_needs_upgrade()` and calling
+ `notmuch_database_upgrade()` as necessary. This has always been the
+ case, but in practise there have been no database upgrades in any
+ released version of Notmuch before now.
+
+Support for indexing mbox files has been dropped
+
+ There has never been proper support for mbox files containing
+ multiple messages, and the support for single-message mbox files has
+ been deprecated since Notmuch 0.15. The support has now been
+ dropped, and all mbox files will be rejected during indexing.
+
+Message header parsing changes
+
+ Notmuch previously had an internal parser for message headers. The
+ parser has now been dropped in favour of letting GMime parse both
+ the headers and the message MIME structure at the same pass. This is
+ mostly an internal change, but the GMime parser is stricter in its
+ interpretation of the headers. This may result in messages with
+ slightly malformed message headers being now rejected.
+
+Command-Line Interface
+----------------------
+
+`notmuch dump` now defaults to `batch-tag` format
+
+ The old format is still available with `--format=sup`.
+
+`notmuch new` has a --quiet option
+
+ This option suppresses the progress and summary reports.
+
+`notmuch insert` respects maildir.synchronize_flags config option
+
+ Do not synchronize tags to maildir flags in `notmuch insert` if the
+ user does not want it.
+
+The commands set consistent exit status codes on failures
+
+ The cli commands now consistently set exit status of 1 on failures,
+ except where explicitly otherwise noted. The notable expections are
+ the status codes for format version mismatches for commands that
+ support formatted output.
+
+Bug fix for checking configured new.tags for invalid tags
+
+ `notmuch new` and `notmuch insert` now check the user configured
+ new.tags for invalid tags, and refuse to apply them, similar to
+ `notmuch tag`. Invalid tags are currently the empty string and tags
+ starting with `-`.
+
+Emacs Interface
+---------------
+
+Init file
+
+ If the file pointed by new variable `notmuch-init-file` (typically
+ `~/.emacs.d/notmuch-config.el`) exists, it is loaded at the end of
+ `notmuch.el`. Users can put their personal notmuch emacs lisp based
+ configuration/customization items there instead of filling
+ `~/.emacs` with these.
+
+Changed format for saved searches
+
+ The format for `notmuch-saved-searches` has changed, but old style
+ saved searches are still supported. The new style means that a saved
+ search can store the desired sort order for the search, and it can
+ store a separate query to use for generating the count notmuch
+ shows.
+
+ The variable is fully customizable and any configuration done
+ through customize should *just work*, with the additional options
+ mentioned above. For manual customization see the documentation for
+ `notmuch-saved-searches`.
+
+ IMPORTANT: a new style notmuch-saved-searches variable will break
+ previous versions of notmuch-emacs (even search will not work); to
+ fix remove the customization for notmuch-saved-searches.