diff --git a/pkgs/orthanc/orthanc.nix b/pkgs/orthanc/orthanc.nix
index cb8b210..889d039 100644
--- a/pkgs/orthanc/orthanc.nix
+++ b/pkgs/orthanc/orthanc.nix
@@ -43,23 +43,15 @@ stdenv.mkDerivation (finalAttrs: {
     #locale
   ];
 
-  cmakeFlags = [
-    "-DALLOW_DOWNLOADS=OFF"
-    "-DSTATIC_BUILD=OFF"
-    "-DCMAKE_BUILD_TYPE=Debug"
-    "-DUSE_SYSTEM_DCMTK=OFF"
-    "-DSTANDALONE_BUILD=ON"
-    "-DDCMTK_DICTIONARY_DIR=${pkgs.dcmtk}/share/dcmtk-${pkgs.dcmtk.version}/"
-  ];
-
   configurePhase = ''
     mkdir Build
     cd ./Build
-    cmake ../OrthancServer/
+    cmake ../OrthancServer/ -DCMAKE_BUILD_TYPE=Release -DDCMTK_DICTIONARY_DIR=${pkgs.dcmtk}/share/dcmtk-${pkgs.dcmtk.version}/ -DBUILD_CONNECTIVITY_CHECKS=OFF "-DDCMTK_LIBRARIES=oflog;ofstd"
   '';
 
   buildPhase = ''
-    make
+    make -j`nproc --all`
+    ./UnitTests
   '';
 
   installPhase = ''