diff --git a/pkgs/development/ocaml-modules/mirage-crypto/default.nix b/pkgs/development/ocaml-modules/mirage-crypto/default.nix
index c2ede31dd3f..ab48e01950e 100644
--- a/pkgs/development/ocaml-modules/mirage-crypto/default.nix
+++ b/pkgs/development/ocaml-modules/mirage-crypto/default.nix
@@ -4,11 +4,11 @@ buildDunePackage rec {
   minimumOCamlVersion = "4.08";
 
   pname = "mirage-crypto";
-  version = "0.8.8";
+  version = "0.8.10";
 
   src = fetchurl {
     url = "https://github.com/mirage/mirage-crypto/releases/download/v${version}/mirage-crypto-v${version}.tbz";
-    sha256 = "19czylfyakckfzzcbqgv9ygl243wix7ak8zkbdcb9hcl2k2shswb";
+    sha256 = "8a5976fe7837491d2fbd1917b77524776f70ae590e9f55cf757cc8951b5481fc";
   };
 
   useDune2 = true;
diff --git a/pkgs/development/ocaml-modules/x509/default.nix b/pkgs/development/ocaml-modules/x509/default.nix
index 289a3891c78..23efd4bb9fc 100644
--- a/pkgs/development/ocaml-modules/x509/default.nix
+++ b/pkgs/development/ocaml-modules/x509/default.nix
@@ -1,4 +1,4 @@
-{ lib, fetchurl, buildDunePackage
+{ lib, fetchurl, buildDunePackage, fetchpatch
 , alcotest, cstruct-unix
 , asn1-combinators, domain-name, fmt, gmap, rresult, mirage-crypto, mirage-crypto-pk
 , logs, base64
@@ -15,6 +15,14 @@ buildDunePackage rec {
     sha256 = "1b4lcphmlyjhdgqi0brakgjp3diwmrj1y9hx87svi5xklw3zik22";
   };
 
+  patches = [
+    # fix tests for mirage-crypto >= 0.8.9, can be removed at next release
+    (fetchpatch {
+      url = "https://github.com/mirleft/ocaml-x509/commit/ba1fdd4432950293e663416a0c454c8c04a71c0f.patch";
+      sha256 = "1rbjf7408772ns3ypk2hyw9v17iy1kcx84plr1rqc56iwk9zzxmr";
+    })
+  ];
+
   useDune2 = true;
 
   buildInputs = [ alcotest cstruct-unix ];