lib/PublicInbox/Config.pm | 17 +++++++++++++----
 t/config.t                | 20 ++++++++++++++++++++

diff --git a/lib/PublicInbox/Config.pm b/lib/PublicInbox/Config.pm
index 01a01c62b9f3b8e6eae60be54ac70b03be3bd14d..ef277c40a55e14c9719a07ecf9546e9c94edd4ef 100644
--- a/lib/PublicInbox/Config.pm
+++ b/lib/PublicInbox/Config.pm
@@ -366,6 +366,17 @@
 	$git;
 }
 
+sub _git_config_bool ($) {
+	my ($val) = @_;
+	if ($val =~ /\A(?:false|no|off|[\-\+]?(?:0x)?0+)\z/i) {
+		0;
+	} elsif ($val =~ /\A(?:true|yes|on|[\-\+]?(?:0x)?[0-9]+)\z/i) {
+		1;
+	} else {
+		undef;
+	}
+}
+
 sub _fill {
 	my ($self, $pfx) = @_;
 	my $ibx = {};
@@ -379,10 +390,8 @@ 	}
 	foreach my $k (qw(obfuscate)) {
 		my $v = $self->{"$pfx.$k"};
 		defined $v or next;
-		if ($v =~ /\A(?:false|no|off|0)\z/) {
-			$ibx->{$k} = 0;
-		} elsif ($v =~ /\A(?:true|yes|on|1)\z/) {
-			$ibx->{$k} = 1;
+		if (defined(my $bval = _git_config_bool($v))) {
+			$ibx->{$k} = $bval;
 		} else {
 			warn "Ignoring $pfx.$k=$v in config, not boolean\n";
 		}
diff --git a/t/config.t b/t/config.t
index b7a4ceb62e030d1efbd31c4ad53e7b0eec548cf6..a4e761500455bfd306c44d3efa626987fc550bbb 100644
--- a/t/config.t
+++ b/t/config.t
@@ -190,4 +190,24 @@ 	is($t1->{-repo_objs}->[0], $t2->{-repo_objs}->[0],
 		'inboxes share ::Git object');
 }
 
+{
+	my $check_git = !!$ENV{CHECK_GIT_BOOL};
+	for my $t (qw(TRUE true yes on 1 +1 -1 13 0x1 0x12 0X5)) {
+		is(PublicInbox::Config::_git_config_bool($t), 1, "$t is true");
+		if ($check_git) {
+			is(`git -c test.val=$t config --bool test.val`,
+				"true\n", "$t matches git-config behavior");
+		}
+	}
+	for my $f (qw(FALSE false no off 0 +0 +000 00 0x00 0X0)) {
+		is(PublicInbox::Config::_git_config_bool($f), 0, "$f is false");
+		if ($check_git) {
+			is(`git -c test.val=$f config --bool test.val`,
+				"false\n", "$f matches git-config behavior");
+		}
+	}
+	is(PublicInbox::Config::_git_config_bool('bogus'), undef,
+		'bogus is undef');
+}
+
 done_testing();