diff --git a/artiq-fast/artiq-board-legacy.nix b/artiq-fast/artiq-board-legacy.nix
new file mode 100644
index 0000000..789d15a
--- /dev/null
+++ b/artiq-fast/artiq-board-legacy.nix
@@ -0,0 +1,99 @@
+# Install Vivado in /opt and add to /etc/nixos/configuration.nix:
+#  nix.sandboxPaths = ["/opt"];
+
+{ pkgs
+, vivado ? import ./vivado.nix { inherit pkgs; }
+}:
+
+let
+  artiqSrc = import ./pkgs/artiq-src.nix { fetchgit = pkgs.fetchgit; };
+  artiqpkgs = import ./default.nix { inherit pkgs; };
+  fetchcargo = import ./fetchcargo.nix {
+    inherit (pkgs) stdenv cacert git;
+    inherit (artiqpkgs) cargo cargo-vendor;
+  };
+  cargoDeps = fetchcargo rec {
+    name = "artiq-firmware-cargo-deps";
+    src = "${artiqSrc}/artiq/firmware";
+    sha256 = (import "${artiqSrc}/artiq/firmware/cargosha256.nix");
+  };
+
+  cargoVendored = pkgs.stdenv.mkDerivation {
+    name = "artiq-firmware-cargo-vendored";
+    src = cargoDeps;
+    phases = [ "unpackPhase" "installPhase" ];
+    installPhase =
+      ''
+      mkdir -p $out/registry
+      cat << EOF > $out/config
+        [source.crates-io]
+        registry = "https://github.com/rust-lang/crates.io-index"
+        replace-with = "vendored-sources"
+
+        [source."https://github.com/m-labs/libfringe"]
+        git = "https://github.com/m-labs/libfringe"
+        rev = "b8a6d8f"
+        replace-with = "vendored-sources"
+
+        [source.vendored-sources]
+        directory = "$out/registry"
+      EOF
+      cp -R * $out/registry
+      '';
+  };
+
+in
+{ target
+, variant
+, src ? null
+, buildCommand ? "python -m artiq.gateware.targets.${target} -V ${variant}"
+, extraInstallCommands ? ""}:
+
+# Board packages are Python modules so that they get added to the ARTIQ Python
+# environment, and artiq_flash finds them.
+pkgs.python3Packages.toPythonModule (pkgs.stdenv.mkDerivation rec {
+  name = "artiq-board-${target}-${variant}-${version}";
+  version = import ./pkgs/artiq-version.nix (with pkgs; { inherit stdenv fetchgit git; });
+  inherit src;
+  phases = [ "buildPhase" "installCheckPhase" "installPhase" "checkPhase" ];
+  buildInputs = [
+    vivado
+    pkgs.gnumake
+    (pkgs.python3.withPackages(ps: with ps; [ jinja2 numpy artiqpkgs.migen artiqpkgs.microscope artiqpkgs.misoc artiqpkgs.jesd204b artiqpkgs.artiq ]))
+    artiqpkgs.cargo
+    artiqpkgs.rustc
+    artiqpkgs.binutils-or1k
+    artiqpkgs.llvm-or1k
+  ];
+  buildPhase = 
+    ''
+    export CARGO_HOME=${cargoVendored}
+    export TARGET_AR=or1k-linux-ar
+    ${buildCommand}
+    '';
+  # temporarily disabled because there is currently always at least one Kasli bitstream
+  # that fails timing and blocks the conda channel.
+  doCheck = false;
+  checkPhase = ''
+    # Search for PCREs in the Vivado output to check for errors
+    check_log() {
+      grep -Pe "$1" artiq_${target}/${variant}/gateware/vivado.log && exit 1 || true
+    }
+    check_log "\d+ constraint not met\."
+    check_log "Timing constraints are not met\."
+    '';
+  installPhase =
+    ''
+    TARGET_DIR=$out/${pkgs.python3Packages.python.sitePackages}/artiq/board-support/${target}-${variant}
+    mkdir -p $TARGET_DIR
+    cp artiq_${target}/${variant}/gateware/top.bit $TARGET_DIR
+    if [ -e artiq_${target}/${variant}/software/bootloader/bootloader.bin ]
+    then cp artiq_${target}/${variant}/software/bootloader/bootloader.bin $TARGET_DIR
+    fi
+    if [ -e artiq_${target}/${variant}/software/runtime ]
+    then cp artiq_${target}/${variant}/software/runtime/runtime.{elf,fbi} $TARGET_DIR
+    else cp artiq_${target}/${variant}/software/satman/satman.{elf,fbi} $TARGET_DIR
+    fi
+    ${extraInstallCommands}
+    '';
+})
diff --git a/artiq-fast/default.nix b/artiq-fast/default.nix
index 91ec860..e11a097 100644
--- a/artiq-fast/default.nix
+++ b/artiq-fast/default.nix
@@ -10,7 +10,11 @@ let
   ];
   boardPackages = pkgs.lib.lists.foldr (board: start:
     let
-      boardBinaries = import ./artiq-board.nix { inherit pkgs; } {
+      packageImport =
+        if artiq6
+        then ./artiq-board.nix
+        else ./artiq-board-legacy.nix;
+      boardBinaries = import packageImport { inherit pkgs; } {
         target = board.target;
         variant = board.variant;
       };
diff --git a/artiq-full.nix b/artiq-full.nix
index d5ae0a5..ca52548 100644
--- a/artiq-full.nix
+++ b/artiq-full.nix
@@ -108,7 +108,11 @@ let
       ]);
 
       vivado = import ./fast/vivado.nix { inherit pkgs; };
-      artiq-board = import ./fast/artiq-board.nix { inherit pkgs vivado; };
+      artiq-board-import =
+        if pkgs.lib.strings.versionAtLeast artiq-fast.artiq.version "6.0"
+        then ./fast/artiq-board.nix
+        else ./fast/artiq-board-legacy.nix;
+      artiq-board = import artiq-board-import { inherit pkgs vivado; };
       conda-artiq-board = import ./conda-artiq-board.nix { inherit pkgs; };
       src = pkgs.fetchgit {
         url = "https://git.m-labs.hk/M-Labs/sinara-systems.git";