diff --git a/sources b/sources
index 9d8b548..b3d3132 100644
--- a/sources
+++ b/sources
@@ -1 +1 @@
-568e0738358450eca69ecf578d48f26c  optipng-0.7.6.tar.gz
+SHA512 (optipng-0.7.7.tar.gz) = c33b7650143ab39944d2c066e07e10273c37024c5bfe7c00475bfb513af96afa081ff388164845d426d3bce624c0282dee574fa150e963f18d3683d821030280