diff --git a/artiq-full.nix b/artiq-full.nix
index 5de005c..c769a1d 100644
--- a/artiq-full.nix
+++ b/artiq-full.nix
@@ -13,7 +13,7 @@ let
         );
       isStandalone = jsonFile:
         (builtins.fromJSON (
-          builtins.readFile "${sinaraSystemsSrc}/${jsonFile}"
+          builtins.readFile (<sinaraSystemsSrc> + "/${jsonFile}")
         )).base == "standalone";
     in
       map (builtins.replaceStrings [".json"] [""]) (
diff --git a/artiq-full/artiq-board.nix b/artiq-full/artiq-board.nix
index 5b37c17..b9cc20e 100644
--- a/artiq-full/artiq-board.nix
+++ b/artiq-full/artiq-board.nix
@@ -16,7 +16,7 @@ let
   cargoDeps = fetchcargo rec {
     name = "artiq-firmware-cargo-deps";
     src = "${artiqSrc}/artiq/firmware";
-    sha256 = (import "${artiqSrc}/artiq/firmware/cargosha256.nix");
+    sha256 = import (artiqSrc + "/artiq/firmware/cargosha256.nix");
   };
 
   cargoVendored = pkgs.stdenv.mkDerivation {