Performance work starts with evidence, not guesses. On an Umbraco 17 site, begin with real-user timings and server-side logs so you can separate slow rendering from slow dependencies.
1. Measure the critical path
Track the pages that matter most to customers: the home page, campaign landing pages, search, and conversion flows. Record Core Web Vitals, response time, cache status, and the size of the HTML and assets. A small baseline makes every improvement testable.
2. Keep rendering intentional
Use Models Builder and strongly typed views where they improve clarity. Keep expensive queries out of loops, avoid loading content you do not render, and make partials do one job. When a component is reused across templates, its data access should be easy to see and profile.
3. Treat caching as a feature
Cache stable content and expensive lookups, but define invalidation deliberately. Test both cache hits and misses. If a page depends on a remote API, set a bounded timeout and a graceful fallback so one dependency cannot hold the whole page hostage.
4. Protect the delivery layer
Compress and size images for their display dimensions, load non-critical scripts later, and verify that static assets are served by the intended backend. After deployment, test the public URL with valid TLS and confirm the response is coming from the right site.
A repeatable release checklist
- Capture a before-and-after measurement.
- Test logged-out and logged-in paths where caching differs.
- Verify assets, redirects, and canonical URLs.
- Watch logs after release and record what changed.
Fast sites are usually the result of small, observable decisions repeated consistently. Measure the path your visitors actually take, improve one bottleneck at a time, and keep the production check part of the definition of done.