diff --git a/artiq-fast/conda-build.nix b/artiq-fast/conda-build.nix
index 581b0dd..fd4b394 100644
--- a/artiq-fast/conda-build.nix
+++ b/artiq-fast/conda-build.nix
@@ -4,36 +4,10 @@
 { pkgs }:
 { name, src, recipe ? "fake-conda"}:
 
-with pkgs;
-
 let
-  condaDeps = [ stdenv.cc xorg.libSM xorg.libICE xorg.libXrender libselinux ];
-  # Use the full Anaconda distribution, which already contains conda-build and its many dependencies,
-  # so we don't have to manually deal with them.
-  condaInstaller = fetchurl {
-    url = "https://repo.anaconda.com/archive/Anaconda3-2019.03-Linux-x86_64.sh";
-    sha256 = "0fmpdd5876ylds98mydmv5klnwlzasa461k0l1f4vhbw96vm3j25";
-  };
-  condaSrcChmod = runCommand "conda-src-chmod" { } "mkdir $out; cp ${condaInstaller} $out/conda-installer.sh; chmod +x $out/conda-installer.sh";
-  condaInstallerEnv = buildFHSUserEnv {
-    name = "conda-installer-env";
-    targetPkgs = pkgs: ([ condaSrcChmod ] ++ condaDeps);
-  };
-
-  condaInstalled = runCommand "conda-installed" { }
-    ''
-    ${condaInstallerEnv}/bin/conda-installer-env -c "${condaSrcChmod}/conda-installer.sh -p $out -b"
-    substituteInPlace $out/lib/python3.7/site-packages/conda/gateways/disk/__init__.py \
-      --replace "os.chmod(path, 0o2775)" "pass"
-    '';
-  condaBuilderEnv = buildFHSUserEnv {
-    name = "conda-builder-env";
-    targetPkgs = pkgs: [ condaInstalled ] ++ condaDeps;
-  };
-
+  condaBuilderEnv = import ./conda-builder-env { inherit pkgs; };
 in stdenv.mkDerivation {
   inherit name src;
-  buildInputs = [ condaBuilderEnv ];
   buildCommand =
     ''
     HOME=`pwd`
diff --git a/artiq-fast/conda-builder-env.nix b/artiq-fast/conda-builder-env.nix
new file mode 100644
index 0000000..e54a8a5
--- /dev/null
+++ b/artiq-fast/conda-builder-env.nix
@@ -0,0 +1,29 @@
+{ pkgs }:
+
+with pkgs;
+
+let
+  condaDeps = [ stdenv.cc xorg.libSM xorg.libICE xorg.libXrender libselinux ];
+  # Use the full Anaconda distribution, which already contains conda-build and its many dependencies,
+  # so we don't have to manually deal with them.
+  condaInstaller = fetchurl {
+    url = "https://repo.anaconda.com/archive/Anaconda3-2019.03-Linux-x86_64.sh";
+    sha256 = "0fmpdd5876ylds98mydmv5klnwlzasa461k0l1f4vhbw96vm3j25";
+  };
+  condaSrcChmod = runCommand "conda-src-chmod" { } "mkdir $out; cp ${condaInstaller} $out/conda-installer.sh; chmod +x $out/conda-installer.sh";
+  condaInstallerEnv = buildFHSUserEnv {
+    name = "conda-installer-env";
+    targetPkgs = pkgs: ([ condaSrcChmod ] ++ condaDeps);
+  };
+
+  condaInstalled = runCommand "conda-installed" { }
+    ''
+    ${condaInstallerEnv}/bin/conda-installer-env -c "${condaSrcChmod}/conda-installer.sh -p $out -b"
+    substituteInPlace $out/lib/python3.7/site-packages/conda/gateways/disk/__init__.py \
+      --replace "os.chmod(path, 0o2775)" "pass"
+    '';
+in
+  buildFHSUserEnv {
+    name = "conda-builder-env";
+    targetPkgs = pkgs: [ condaInstalled ] ++ condaDeps;
+  }