diff --git a/pkgs/applications/networking/browsers/chromium/common.nix b/pkgs/applications/networking/browsers/chromium/common.nix
index 8ce7c89bf78..34bac9716cc 100644
--- a/pkgs/applications/networking/browsers/chromium/common.nix
+++ b/pkgs/applications/networking/browsers/chromium/common.nix
@@ -4,7 +4,7 @@
 , bzip2, flac, speex, libopus
 , libevent, expat, libjpeg, snappy
 , libpng, libcap
-, xdg_utils, yasm, minizip, libwebp
+, xdg_utils, yasm, nasm, minizip, libwebp
 , libusb1, pciutils, nss, re2, zlib
 
 , python2Packages, perl, pkgconfig
@@ -72,14 +72,14 @@ let
     in attrs: concatStringsSep " " (attrValues (mapAttrs toFlag attrs));
 
   gnSystemLibraries = [
-    "flac" "libwebp" "libxslt" "yasm" "opus" "snappy" "libpng"
+    "flac" "libwebp" "libxslt" "opus" "snappy" "libpng"
     # "zlib" # version 77 reports unresolved dependency on //third_party/zlib:zlib_config
     # "libjpeg" # fails with multiple undefined references to chromium_jpeg_*
     # "re2" # fails with linker errors
     # "ffmpeg" # https://crbug.com/731766
     # "harfbuzz-ng" # in versions over 63 harfbuzz and freetype are being built together
                     # so we can't build with one from system and other from source
-  ];
+  ] ++ optional (upstream-info.channel != "dev") "yasm";
 
   opusWithCustomModes = libopus.override {
     withCustomModes = true;
@@ -89,12 +89,12 @@ let
     bzip2 flac speex opusWithCustomModes
     libevent expat libjpeg snappy
     libpng libcap
-    xdg_utils yasm minizip libwebp
+    xdg_utils minizip libwebp
     libusb1 re2 zlib
     ffmpeg libxslt libxml2
     # harfbuzz # in versions over 63 harfbuzz and freetype are being built together
                # so we can't build with one from system and other from source
-  ];
+  ] ++ (if upstream-info.channel == "dev" then [ nasm ] else [ yasm ]);
 
   # build paths and release info
   packageName = extraAttrs.packageName or extraAttrs.name;
@@ -224,8 +224,9 @@ let
       ln -s ${llvmPackages.llvm}/bin/llvm-ar    third_party/llvm-build/Release+Asserts/bin/llvm-ar
     '';
 
-    gnFlags = mkGnFlags ({
+    gnFlags = mkGnFlags (optionalAttrs (upstream-info.channel != "dev") {
       linux_use_bundled_binutils = false;
+    } // {
       use_lld = false;
       use_gold = true;
       gold_path = "${stdenv.cc}/bin";
diff --git a/pkgs/applications/networking/browsers/chromium/default.nix b/pkgs/applications/networking/browsers/chromium/default.nix
index df1dcb413e1..9e46d061a30 100644
--- a/pkgs/applications/networking/browsers/chromium/default.nix
+++ b/pkgs/applications/networking/browsers/chromium/default.nix
@@ -43,6 +43,15 @@ let
           sha256 = "00y2d35wvqmx9glaqhfb62wdgbfpwr77v0934nnvh9ks71vnsjqy";
         };
       });
+    } // lib.optionalAttrs (channel == "dev") {
+      gnChromium = gn.overrideAttrs (oldAttrs: {
+        version = "2020-05-19";
+        src = fetchgit {
+          url = "https://gn.googlesource.com/gn";
+          rev = "d0a6f072070988e7b038496c4e7d6c562b649732";
+          sha256 = "0197msabskgfbxvhzq73gc3wlr3n9cr4bzrhy5z5irbvy05lxk17";
+        };
+      });
     });
 
     browser = callPackage ./browser.nix { inherit channel enableWideVine; };
diff --git a/pkgs/applications/networking/browsers/chromium/upstream-info.nix b/pkgs/applications/networking/browsers/chromium/upstream-info.nix
index 943b5ed34d6..ced9c2454b5 100644
--- a/pkgs/applications/networking/browsers/chromium/upstream-info.nix
+++ b/pkgs/applications/networking/browsers/chromium/upstream-info.nix
@@ -6,9 +6,9 @@
     version = "84.0.4147.38";
   };
   dev = {
-    sha256 = "04jbh8bsvqkm8mdsgyv0465fq5lhz0nn0mcs07kj5hnmzx1g2f3a";
-    sha256bin64 = "0d9knpqbps06wgfgp2s7z693dqiip0m771mv3j2856h5v9rv210l";
-    version = "85.0.4158.4";
+    sha256 = "07h3i4ab7yj05ndrqchzf3f9wr809qb3dj2gfc1653mkjmba8h07";
+    sha256bin64 = "10jdq5mr7qby0m26l5lbsqcbh9bhjdpmpbkkcvv9wm2259rwjxr5";
+    version = "85.0.4164.2";
   };
   stable = {
     sha256 = "10vg0fmwlkzpnixhhhcwccxshqdfq7rh0ribij7wgkw42bv0bi0j";