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 # feed2imap-go
 
-A software to convert rss feeds into mails.
+A software to convert rss feeds into mails. feed2imap-go acts an an RSS/Atom feed aggregator. After downloading feeds (over HTTP or HTTPS), it uploads them to a specified folder of an IMAP mail server. The user can then access the feeds using their preferred client (Mutt, Evolution, Mozilla Thunderbird, webmail,...).
 
-It is a rewrite in Go of the wonderful, but unfortunately now unmaintained, [feed2imap](https://github.com/feed2imap/feed2imap).
-It aims to be compatible in functionality and configuration, serving as a drop-in replacement.
+It is a rewrite in Go of the wonderful, but unfortunately now unmaintained, [feed2imap](https://github.com/feed2imap/feed2imap). It also includes the features that up to now only lived on [my own branch][nec].
+
+It aims to be compatible in functionality and configuration, and should mostly work as a drop-in replacement (but see [Changes](#changes)).
 
 ## Features
 
-TBD
+* Support for most feed formats. See [gofeed documentation](https://github.com/mmcdole/gofeed/blob/master/README.md#features) for details.
+* Connection to any IMAP server, using IMAP, IMAP+STARTTLS, or IMAPS.
+* Detection of duplicates: Heuristics what feed items have already been uploaded.
+* Update mechanism: When a feed item is updated, so is the mail. (_TODO_: [issue #9][i9])
+* Detailed configuration options per feed (fetch frequency, should images be included, tune change heuristics, ...)
+
+## Changes
+
+### Additions to feed2imap
+
+* groups (_details TBD_)
+* heavier use of parallel processing (it's Go after all ;))
+* Global `target` and each feed only specifies only the folder relative to that target. (feature contained also in [fork of the original][nec]) 
+
+### Subtle differences
 
-### Additions from feed2imap
+* **Feed rendering**: Unfortunately, semantics of RSS and Atom tags are very broad. As we use a different feed parser library than the original, the interpretation (e.g., what tag is "the author") can differ.
+* **Caching**: We do not implement the caching algorithm of feed2imap point by point. In general we opted for less heuristics and more optimism (belief that GUID is filled correctly; belief that the difference between publishing and update date is adhered to). If this results in a problem, file a bug and include the `X-Feed2Imap-Reason` header of the mail.
+* **Configuration**: We took the liberty to restructure the configuration options. Old configs are supported, but a warning is issued when an option should now be in another place or is no longer supported (that is, without function).
 
-* groups
+### Unsupported features of feed2imap
 
-### Unsupported features compared to feed2imap
+* IMAP-Target per Feed ([issue #6][i6]); targets only specify the folder relative to the global target
+* Maildir ([issue #4][i4])
+* Scripts that run pre/post a feed entryfeed2imap is an RSS/Atom feed aggregator. After
+Downloading feeds (over HTTP or HTTPS), it uploads them to a specified
+folder of an IMAP mail server. The user can then access the feeds using
+Mutt, Evolution, Mozilla Thunderbird or even a webmail.
 
-TBD
+[i6]: https://github.com/Necoro/feed2imap-go/issues/6
+[i4]: https://github.com/Necoro/feed2imap-go/issues/4
+[i9]: https://github.com/Necoro/feed2imap-go/issues/9
+[nec]: https://github.com/Necoro/feed2imap