diff --git a/pkgs/os-specific/linux/decklink/default.nix b/pkgs/os-specific/linux/decklink/default.nix
index 8d0d167bc7f5..63bfe4a63af2 100644
--- a/pkgs/os-specific/linux/decklink/default.nix
+++ b/pkgs/os-specific/linux/decklink/default.nix
@@ -1,14 +1,16 @@
-{ stdenv, lib, requireFile, fetchpatch, kernel }:
+{ stdenv
+, lib
+, blackmagic-desktop-video
+, kernel
+}:
 
 stdenv.mkDerivation rec {
   pname = "decklink";
-  version = "12.2a12";
 
-  src = requireFile {
-    name = "Blackmagic_Desktop_Video_Linux_${lib.versions.majorMinor version}.tar.gz";
-    url = "https://www.blackmagicdesign.com/support/download/33abc1034cd54cf99101f9acd2edd93d/Linux";
-    sha256 = "62954a18b60d9040aa4a959dff30ac9c260218ef78d6a63cbb243788f7abc05f";
-  };
+  # the download is a horrible curl mess. we reuse it between the kernel module
+  # and desktop service, since the version of the two have to match anyways.
+  # See pkgs/tools/video/blackmagic-desktop-video/default.nix for more.
+  inherit (blackmagic-desktop-video) src version;
 
   KERNELDIR = "${kernel.dev}/lib/modules/${kernel.modDirVersion}/build";
   INSTALL_MOD_PATH = placeholder "out";
diff --git a/pkgs/tools/video/blackmagic-desktop-video/default.nix b/pkgs/tools/video/blackmagic-desktop-video/default.nix
index 48e16d3b94b6..dc6f2eff7873 100644
--- a/pkgs/tools/video/blackmagic-desktop-video/default.nix
+++ b/pkgs/tools/video/blackmagic-desktop-video/default.nix
@@ -1,20 +1,78 @@
-{ stdenv, requireFile, lib,
-  libcxx, libcxxabi
+{ stdenv
+, cacert
+, curl
+, runCommandLocal
+, lib
+, autoPatchelfHook
+, libcxx
+, libcxxabi
+, libGL
+, gcc7
 }:
 
 stdenv.mkDerivation rec {
   pname = "blackmagic-desktop-video";
-  version = "12.2a12";
+  version = "12.5a15";
 
   buildInputs = [
-    libcxx libcxxabi
+    autoPatchelfHook
+    libcxx
+    libcxxabi
+    libGL
+    gcc7.cc.lib
   ];
 
-  src = requireFile {
-    name = "Blackmagic_Desktop_Video_Linux_${lib.versions.majorMinor version}.tar.gz";
-    url = "https://www.blackmagicdesign.com/support/download/33abc1034cd54cf99101f9acd2edd93d/Linux";
-    sha256 = "62954a18b60d9040aa4a959dff30ac9c260218ef78d6a63cbb243788f7abc05f";
-  };
+  # yes, the below download function is an absolute mess.
+  # blame blackmagicdesign.
+  src = runCommandLocal "${pname}-${lib.versions.majorMinor version}-src.tar.gz"
+    rec {
+      outputHashMode = "recursive";
+      outputHashAlgo = "sha256";
+      outputHash = "sha256-ss7Ab5dy7cmXp9LBirFXMeGY4ZbYHvWnXmYvNeBq0RY=";
+
+      impureEnvVars = lib.fetchers.proxyImpureEnvVars;
+
+      nativeBuildInputs = [ curl ];
+
+      # ENV VARS
+      SSL_CERT_FILE = "${cacert}/etc/ssl/certs/ca-bundle.crt";
+
+      # from the URL that the POST happens to, see browser console
+      DOWNLOADID = "fecacc0f9b2f4c2e8bf2863e9e26c8e1";
+      # from the URL the download page where you click the "only download" button is at
+      REFERID = "052d944af6744608b27da496dfc4396d";
+      SITEURL = "https://www.blackmagicdesign.com/api/register/us/download/${DOWNLOADID}";
+
+      USERAGENT = builtins.concatStringsSep " " [
+        "User-Agent: Mozilla/5.0 (X11; Linux ${stdenv.targetPlatform.linuxArch})"
+        "AppleWebKit/537.36 (KHTML, like Gecko)"
+        "Chrome/77.0.3865.75"
+        "Safari/537.36"
+      ];
+
+      REQJSON = builtins.toJSON {
+        "country" = "nl";
+        "downloadOnly" = true;
+        "platform" = "Linux";
+        "policy" = true;
+      };
+
+    } ''
+    RESOLVEURL=$(curl \
+      -s \
+      -H "$USERAGENT" \
+      -H 'Content-Type: application/json;charset=UTF-8' \
+      -H "Referer: https://www.blackmagicdesign.com/support/download/$REFERID/Linux" \
+      --data-ascii "$REQJSON" \
+      --compressed \
+      "$SITEURL")
+
+    curl \
+      --retry 3 --retry-delay 3 \
+      --compressed \
+      "$RESOLVEURL" \
+      > $out
+  '';
 
   postUnpack = ''
     tar xf Blackmagic_Desktop_Video_Linux_${lib.versions.majorMinor version}/other/${stdenv.hostPlatform.uname.processor}/desktopvideo-${version}-${stdenv.hostPlatform.uname.processor}.tar.gz
@@ -28,8 +86,6 @@ stdenv.mkDerivation rec {
     cp -r $unpacked/usr/share/doc/desktopvideo $out/share/doc
     cp $unpacked/usr/lib/*.so $out/lib
     cp $unpacked/usr/lib/systemd/system/DesktopVideoHelper.service $out/lib/systemd/system
-    ln -s ${libcxx}/lib/* ${libcxxabi}/lib/* $out/lib
-    cp $unpacked/usr/lib/blackmagic/DesktopVideo/libgcc_s.so.1 $out/lib/
     cp $unpacked/usr/lib/blackmagic/DesktopVideo/DesktopVideoHelper $out/bin/
 
     substituteInPlace $out/lib/systemd/system/DesktopVideoHelper.service --replace "/usr/lib/blackmagic/DesktopVideo/DesktopVideoHelper" "$out/bin/DesktopVideoHelper"
@@ -37,12 +93,8 @@ stdenv.mkDerivation rec {
     runHook postInstall
   '';
 
-
-  postFixup = ''
-    patchelf --set-interpreter ${stdenv.cc.bintools.dynamicLinker} \
-      --set-rpath "$out/lib:${lib.makeLibraryPath [ libcxx libcxxabi ]}" \
-      $out/bin/DesktopVideoHelper
-  '';
+  # i know this is ugly, but it's the cleanest way i found to tell the DesktopVideoHelper where to find its own library
+  appendRunpaths = [ "$ORIGIN/../lib" ];
 
   meta = with lib; {
     homepage = "https://www.blackmagicdesign.com/support/family/capture-and-playback";