fingerprint deployed stylesheet assets

nix/site.nix

@@ -1,5 +1,10 @@
 { pkgs }:
 
+let
+  stylesheetHash = builtins.substring 0 12 (builtins.hashFile "sha256" ../site/styles.css);
+  stylesheetFileName = "styles-${stylesheetHash}.css";
+in
+
 pkgs.stdenvNoCC.mkDerivation {
   pname = "tide-landing-page";
   version = "1.0.0";
@@ -12,6 +17,11 @@ pkgs.stdenvNoCC.mkDerivation {
 
     mkdir -p "$out"
     cp -R . "$out"
+    mv "$out/styles.css" "$out/${stylesheetFileName}"
+    substituteInPlace "$out/index.html" \
+      --replace-fail \
+      'href="/styles.css"' \
+      'href="/${stylesheetFileName}"'
 
     runHook postInstall
   '';

nix/tests/module.nix

@@ -25,8 +25,7 @@ let
   };
   evaluatedConfig = evaluatedSystem.config;
   landingPage = self.packages.${system}.landing-page;
-  stylesheetHash =
-    builtins.substring 0 12 (builtins.hashFile "sha256" ../../site/styles.css);
+  stylesheetHash = builtins.substring 0 12 (builtins.hashFile "sha256" ../../site/styles.css);
   stylesheetFileName = "styles-${stylesheetHash}.css";
   landingVirtualHost = evaluatedConfig.services.nginx.virtualHosts."torahimderecheretz.com";
   discourseConfig = evaluatedConfig.services.discourse;