Documentation/public-inbox-config.pod |  8 ++++++++
 lib/PublicInbox/Config.pm             |  3 ++-
 lib/PublicInbox/WWW.pm                | 20 +++++++++++++++++++-

diff --git a/Documentation/public-inbox-config.pod b/Documentation/public-inbox-config.pod
index 5ee93e2e736cc5883951893ac1106966564389df..9647e4a46cef6924f5127a48532d5f7f6c3d1b0e 100644
--- a/Documentation/public-inbox-config.pod
+++ b/Documentation/public-inbox-config.pod
@@ -209,6 +209,14 @@ code repositories known to cgit.
 
 Macro expansion (e.g. C<$HTTP_HOST>) is not yet supported.
 
+=item publicinbox.cgitbin
+
+A path to the C<cgit.cgi> executable.  The L<PublicInbox::WWW>
+interface can spawn cgit as a fallback if the publicinbox.cgitrc
+directive is configured.
+
+Default: /usr/lib/cgit/cgit.cgi
+
 =back
 
 =head2 NAMED LIMITER (PSGI)
diff --git a/lib/PublicInbox/Config.pm b/lib/PublicInbox/Config.pm
index 4b24672003a1d98132c1c80c322bc49824204ad1..ec9a469c3516183da8459336751571fdfd6ef12e 100644
--- a/lib/PublicInbox/Config.pm
+++ b/lib/PublicInbox/Config.pm
@@ -30,6 +30,7 @@ 	$self->{-by_newsgroup} ||= {};
 	$self->{-no_obfuscate} ||= {};
 	$self->{-limiters} ||= {};
 	$self->{-code_repos} ||= {}; # nick => PublicInbox::Git object
+	$self->{-cgitrc_unparsed} = $self->{'publicinbox.cgitrc'};
 
 	if (my $no = delete $self->{'publicinbox.noobfuscate'}) {
 		$no = _array($no);
@@ -244,7 +245,7 @@ 	my ($self, $nick) = @_;
 	my $pfx = "coderepo.$nick";
 
 	# TODO: support gitweb and other repository viewers?
-	if (defined(my $cgitrc = delete $self->{'publicinbox.cgitrc'})) {
+	if (defined(my $cgitrc = delete $self->{-cgitrc_unparsed})) {
 		parse_cgitrc($self, $cgitrc, 0);
 	}
 	my $dir = $self->{"$pfx.dir"}; # aka "GIT_DIR"
diff --git a/lib/PublicInbox/WWW.pm b/lib/PublicInbox/WWW.pm
index 7ed4f654c69085977fb17a3a0764919624e21418..6e14e8c1d87ab9886c3d404e3ac310ab1f3317de 100644
--- a/lib/PublicInbox/WWW.pm
+++ b/lib/PublicInbox/WWW.pm
@@ -15,6 +15,7 @@ use 5.008;
 use strict;
 use warnings;
 use bytes (); # only for bytes::length
+use Plack::Util;
 use PublicInbox::Config;
 use PublicInbox::Hval;
 use URI::Escape qw(uri_unescape);
@@ -154,6 +155,7 @@ 			PublicInbox::NewsWWW)) {
 		eval "require $_;";
 	}
 	if (ref($self)) {
+		$self->cgit;
 		$self->stylesheets_prepare($_) for ('', '../', '../../');
 	}
 }
@@ -188,7 +190,9 @@ 	# sometimes linkifiers (not ours!) screw up automatic link
 	# generation and link things intended for nntp:// to https?://,
 	# so try to infer links and redirect them to the appropriate
 	# list URL.
-	$www->news_www->call($ctx->{env});
+	my $env = $ctx->{env};
+	my $res = $www->news_www->call($env);
+	$res->[0] == 404 ? $www->cgit->call($env) : $res;
 }
 
 # returns undef if valid, array ref response if invalid
@@ -464,6 +468,20 @@ 	my ($self) = @_;
 	$self->{news_www} ||= do {
 		require PublicInbox::NewsWWW;
 		PublicInbox::NewsWWW->new($self->{pi_config});
+	}
+}
+
+sub cgit {
+	my ($self) = @_;
+	$self->{cgit} ||= do {
+		my $pi_config = $self->{pi_config};
+
+		if (defined($pi_config->{'publicinbox.cgitrc'})) {
+			require PublicInbox::Cgit;
+			PublicInbox::Cgit->new($pi_config);
+		} else {
+			Plack::Util::inline_object(call => sub { r404() });
+		}
 	}
 }