lib/PublicInbox/Fetch.pm     | 2 ++
 lib/PublicInbox/LeiMirror.pm | 2 ++

diff --git a/lib/PublicInbox/Fetch.pm b/lib/PublicInbox/Fetch.pm
index 5261cad198552883ce162ea0fa3b84e908939da1..364271e8ccd918537db42ae01e3d0d6734ed84fa 100644
--- a/lib/PublicInbox/Fetch.pm
+++ b/lib/PublicInbox/Fetch.pm
@@ -221,7 +221,9 @@ 	if ($ft) {
 		if ($mculled) {
 			my $json = PublicInbox::Config->json->encode($m1);
 			my $fn = $ft->filename;
+			my $mtime = (stat($fn))[9];
 			gzip(\$json => $fn) or die "gzip: $GzipError";
+			utime($mtime, $mtime, $fn) or die "utime(..., $fn): $!";
 		}
 		PublicInbox::LeiMirror::ft_rename($ft, $mf, 0666);
 	}
diff --git a/lib/PublicInbox/LeiMirror.pm b/lib/PublicInbox/LeiMirror.pm
index e20d30b48546fc9c1344d78b9d699858af4db0a6..fa1d2e88b20bbec1bf6a745418ab51c141f40381 100644
--- a/lib/PublicInbox/LeiMirror.pm
+++ b/lib/PublicInbox/LeiMirror.pm
@@ -408,7 +408,9 @@ 		# write the smaller manifest if epochs were skipped so
 		# users won't have to delete manifest if they +w an
 		# epoch they no longer want to skip
 		my $json = PublicInbox::Config->json->encode($m);
+		my $mtime = (stat($fn))[9];
 		gzip(\$json => $fn) or die "gzip: $GzipError";
+		utime($mtime, $mtime, $fn) or die "utime(..., $fn): $!";
 	}
 	ft_rename($ft, "$self->{dst}/manifest.js.gz", 0666);
 }