added info on node versions in readme

README.md

@@ -52,8 +52,13 @@ Source: https://www.programmfabrik.de/en/assignment-frontend-backend-developer-j
 
 ## Usage
 
+Tested to work on Node.js v20.15.1, should probably also work on all v20 and v22.
+Not tested with earlier Node.js versions.
+Node.js v23.2.0 (unstable; probably other releases of Node.js v23 as well) is known to result in errors inside tests runner (in third-party code).
+
 * `npm ci` to install dependencies;
 * `npm run check-and-start` to run linting, typechecking, tests, build everything and serve it from `PORT` environment variable or from port 3000.
+* `npm run build-and-start` to only build everything and serve (if linting, typechecking or tests are failing for some reason).
 
 (Yes, strictly speaking it's not just a static webpage with a bunch of client-side scripts.
 It's better. See "User interface" section in "Design" for more details.)