TODO                    | 5 +++++
 lib/PublicInbox/Feed.pm | 4 ++--
 lib/PublicInbox/MDA.pm  | 2 +-
 lib/PublicInbox/View.pm | 4 ++++

diff --git a/TODO b/TODO
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..00df8bd375bf7f907c50858f668440942dc8ce6b 100644
--- a/TODO
+++ b/TODO
@@ -0,0 +1,5 @@
+* configurable constants (quote folding, index limits)
+* use tags as date-based skiplists for navigating history
+* per-message views should be able to quickly navigate do replies.
+  (n.b.: this is SMTP, we must account for out-of-order delivery)
+* NNTP server (is there demand for one?)
diff --git a/lib/PublicInbox/Feed.pm b/lib/PublicInbox/Feed.pm
index 12ac8a95be278bb046962e1233b4442707a59df9..6996f374e555a4f55d565fda80fe3b119369e3b0 100644
--- a/lib/PublicInbox/Feed.pm
+++ b/lib/PublicInbox/Feed.pm
@@ -9,8 +9,8 @@ use Date::Parse qw(strptime str2time);
 use PublicInbox::Hval;
 use PublicInbox::GitCatFile;
 use constant {
-	DATEFMT => '%Y-%m-%dT%H:%M:%SZ',
-	MAX_PER_PAGE => 25,
+	DATEFMT => '%Y-%m-%dT%H:%M:%SZ', # atom standard
+	MAX_PER_PAGE => 25, # this needs to be tunable
 };
 
 # main function
diff --git a/lib/PublicInbox/MDA.pm b/lib/PublicInbox/MDA.pm
index ee4d0afe9715c27349d737ef034475ee80b93fdc..e2b2f9143083c0b1979d283fda7d2b985096e9a9 100644
--- a/lib/PublicInbox/MDA.pm
+++ b/lib/PublicInbox/MDA.pm
@@ -6,7 +6,7 @@ use warnings;
 use Email::Address;
 use Encode qw/decode/;
 use Date::Parse qw(strptime);
-use constant MAX_SIZE => 1024 * 500; # same as spamc default
+use constant MAX_SIZE => 1024 * 500; # same as spamc default, should be tunable
 use constant cmd => qw/ssoma-mda -1/;
 
 # drop plus addressing for matching
diff --git a/lib/PublicInbox/View.pm b/lib/PublicInbox/View.pm
index 52e8f0b290b59692f50693af0999c525493af6c9..674d7b7cdfb73c77172c59485dea33c60908d3f7 100644
--- a/lib/PublicInbox/View.pm
+++ b/lib/PublicInbox/View.pm
@@ -8,8 +8,11 @@ use URI::Escape qw/uri_escape_utf8/;
 use Encode qw/find_encoding/;
 use Encode::MIME::Header;
 use Email::MIME::ContentType qw/parse_content_type/;
+
+# TODO: make these constants tunable
 use constant MAX_INLINE_QUOTED => 5;
 use constant MAX_TRUNC_LEN => 72;
+
 *ascii_html = *PublicInbox::Hval::ascii_html;
 
 my $enc_utf8 = find_encoding('UTF-8');
@@ -92,6 +95,7 @@ sub add_text_body_short {
 	my ($enc, $part, $part_nr, $full_pfx) = @_;
 	my $n = 0;
 	my $s = ascii_html($enc->decode($part->body));
+	# TODO: fold the "so-and-so wrote:" attribute line here, too:
 	$s =~ s!^((?:(?:>[^\n]*)\n)+)!
 		my $cur = $1;
 		my @lines = split(/\n/, $cur);