diff --git a/flake.lock b/flake.lock
index 04219d9b..095c1bfc 100644
--- a/flake.lock
+++ b/flake.lock
@@ -15,17 +15,17 @@
         "stable": "stable"
       },
       "locked": {
-        "lastModified": 1712580297,
-        "narHash": "sha256-3zpAbtDN7eFKjzCUExdl6lpidzprw5wzNEduQ1zGWHs=",
+        "lastModified": 1720168760,
+        "narHash": "sha256-tSUBdZmNeB1tURt7fqeH/xKArumzsE14PwsI8beDlro=",
         "owner": "EasyCrypt",
         "repo": "easycrypt",
-        "rev": "4201fddc14b81d2a69a33f034c9c7db4dfd58d0e",
+        "rev": "a9e31ff5f758ef62453d76de382a10ee718afc51",
         "type": "github"
       },
       "original": {
         "owner": "EasyCrypt",
         "repo": "easycrypt",
-        "rev": "4201fddc14b81d2a69a33f034c9c7db4dfd58d0e",
+        "rev": "a9e31ff5f758ef62453d76de382a10ee718afc51",
         "type": "github"
       }
     },
diff --git a/flake.nix b/flake.nix
index 5b3574df..10e35d24 100644
--- a/flake.nix
+++ b/flake.nix
@@ -4,7 +4,7 @@
   inputs = {
     nixpkgs.url = "nixpkgs/release-24.05";
 
-    easycrypt.url = "github:EasyCrypt/easycrypt/4201fddc14b81d2a69a33f034c9c7db4dfd58d0e";
+    easycrypt.url = "github:EasyCrypt/easycrypt/a9e31ff5f758ef62453d76de382a10ee718afc51";
     jasmin = {
       url = "github:jasmin-lang/jasmin/e4640e7dcdb01d1ba63617a5d78456e1209d699c";
       flake = false;
@@ -35,7 +35,7 @@
             packages = [
               ec.with_provers
               pkgs.why3
-              pkgs.valgrind
+              (pkgs.lib.optional pkgs.stdenv.isLinux pkgs.valgrind)
             ];
 
             ECARGS = "-I Jasmin:${jasmin}/eclib";