+What sucks about public-inbox
+-----------------------------
+
+* Lack of push notification. On the other hand, feeds seem popular.
+
+* some (mostly GUI) mail clients cannot set In-Reply-To headers
+ properly without the original message.
+
+Scalability notes
+-----------------
+
+Even with shallow clone, storing the history of large/busy mailing lists
+may place much burden on subscribers and servers. However, having a
+single (or few) refs representing the entire history of a list is good
+for small lists since it's easier to look up a message by Message-ID, so
+we want to avoid splitting refs with independent histories.
+
+ssoma will likely grow its own built-in ref rotation system based on
+message count (not rotating at fixed time intervals). This would
+split the histories and require O(n) lookup time based on Message-ID,
+where `n' is the number of history splits.
+