Start linting with eslint

nix/checks.nix

@@ -21,7 +21,7 @@
           include = [
             ../package.json
             ../tsconfig.json
-            ../.eslintrc.json
+            ../.eslintrc.yaml
             ../.parcelrc
             ../.posthtmlrc
             ../.prettierrc
@@ -38,7 +38,7 @@
 
         checkPhase = ''
           mkdir -p $out
-          ${concatStringsSep "\n" (map (command: "${command} > $out/check.log") checkCommands)}
+          ${concatStringsSep "\n" (map (command: "${command} | tee $out/check.log") checkCommands)}
         '';
 
         doCheck = true;
@@ -58,4 +58,10 @@ in {
       "npm run check"
     ];
   };
+
+  lints = mkNodeCheck {
+    checkCommands = [
+      "npm run lint"
+    ];
+  };
 }