diff --git a/pkgs/development/libraries/libressl/default.nix b/pkgs/development/libraries/libressl/default.nix
index 9e0492c802b3..00bf49f5dc25 100644
--- a/pkgs/development/libraries/libressl/default.nix
+++ b/pkgs/development/libraries/libressl/default.nix
@@ -174,5 +174,20 @@ in
   libressl_4_0 = generic {
     version = "4.0.0";
     hash = "sha256-TYQZVfCsw9/HHQ49018oOvRhIiNQ4mhD/qlzHAJGoeQ=";
+    # Fixes build on loongarch64
+    # https://github.com/libressl/portable/pull/1146
+    patches = [
+      (fetchpatch {
+        name = "0100-ALT-basic-loongarch64-support.patch";
+        url = "https://git.altlinux.org/gears/L/LibreSSL.git?p=LibreSSL.git;a=blob_plain;f=patches/0100-ALT-basic-loongarch64-support.patch;hb=70ddea860b8b62531bd3968bf4d7a5c4b7086776";
+        stripLen = 2;
+        extraPrefix = "";
+        postFetch = ''
+          substituteInPlace "$out" \
+            --replace-fail "a//dev/null" "/dev/null"
+        '';
+        hash = "sha256-dEdtmHHiR7twAqgebXv1Owle/KYCak71NhDCp0PdseU=";
+      })
+    ];
   };
 }