diff --git a/nixos/modules/services/misc/home-assistant.nix b/nixos/modules/services/misc/home-assistant.nix
index 07b14bb6764..b9a97296779 100644
--- a/nixos/modules/services/misc/home-assistant.nix
+++ b/nixos/modules/services/misc/home-assistant.nix
@@ -134,8 +134,10 @@ in {
       description = "Home Assistant";
       after = [ "network.target" ];
       preStart = lib.optionalString (cfg.config != null) ''
-        rm -f ${cfg.configDir}/configuration.yaml
-        ln -s ${configFile} ${cfg.configDir}/configuration.yaml
+        config=${cfg.configDir}/configuration.yaml
+        rm -f $config
+        ${pkgs.remarshal}/bin/json2yaml -i ${configFile} -o $config
+        chmod 444 $config
       '';
       serviceConfig = {
         ExecStart = "${package}/bin/hass --config '${cfg.configDir}'";
diff --git a/nixos/tests/home-assistant.nix b/nixos/tests/home-assistant.nix
index 2e45dc78471..4ebccb7ab86 100644
--- a/nixos/tests/home-assistant.nix
+++ b/nixos/tests/home-assistant.nix
@@ -51,9 +51,9 @@ in {
     startAll;
     $hass->waitForUnit("home-assistant.service");
 
-    # Since config is specified using a Nix attribute set,
-    # configuration.yaml is a link to the Nix store
-    $hass->succeed("test -L ${configDir}/configuration.yaml");
+    # The config is specified using a Nix attribute set,
+    # but then converted from JSON to YAML
+    $hass->succeed("test -f ${configDir}/configuration.yaml");
 
     # Check that Home Assistant's web interface and API can be reached
     $hass->waitForOpenPort(8123);