diff --git a/pkgs/development/coq-modules/gaia-hydras/default.nix b/pkgs/development/coq-modules/gaia-hydras/default.nix
index 325d47dede03..f27c2e4f51fb 100644
--- a/pkgs/development/coq-modules/gaia-hydras/default.nix
+++ b/pkgs/development/coq-modules/gaia-hydras/default.nix
@@ -13,9 +13,9 @@ mkCoqDerivation {
   pname = "gaia-hydras";
   repo = "hydra-battles";
 
-  release."0.5".sha256 = "121pcbn6v59l0c165ha9n00whbddpy11npx2y9cn7g879sfk2nqk";
-  release."0.6".sha256 = "1dri4sisa7mhclf8w4kw7ixs5zxm8xyjr034r1377p96rdk3jj0j";
-  release."0.9".sha256 = "sha256-wlK+154owQD/03FB669KCjyQlL2YOXLCi0KLSo0DOwc=";
+  release."0.5".hash = "sha256:121pcbn6v59l0c165ha9n00whbddpy11npx2y9cn7g879sfk2nqk";
+  release."0.6".hash = "sha256:1dri4sisa7mhclf8w4kw7ixs5zxm8xyjr034r1377p96rdk3jj0j";
+  release."0.9".hash = "sha256-wlK+154owQD/03FB669KCjyQlL2YOXLCi0KLSo0DOwc=";
   releaseRev = (v: "v${v}");
 
   inherit version;