the latter is missing from OpenBSD and maybe other distros.
* improve performance and avoid head-of-line blocking on slow storage
+
+* share "git cat-file --batch" processes across inboxes to avoid
+ bumping into /proc/sys/fs/pipe-user-pages-* limits
+
+* make "git cat-file --batch" detect unlinked packfiles so we don't
+ have to restart processes (very long-term)
+
+* support searching based on `git-patch-id --stable` to improve
+ bidirectional mapping of commits <=> emails
+
+* linter to check validity of config file
+
+* linter option and WWW endpoint to graph relationships and flows
+ between inboxes, addresses maildirs, coderepos, etc...
+
+* pygments support - via Python script similar to `git cat-file --batch'
+ to avoid startup penalty. pygments.rb (Ruby) can be inspiration, too.