https://klikukliku.dev/tags/fingerprinting/Recent content in Fingerprinting on Kliku KlikuHugoenTue, 27 Jan 2026 00:00:00 +0000https://klikukliku.dev/posts/hugo-js-optimization/Tue, 27 Jan 2026 00:00:00 +0000https://klikukliku.dev/posts/hugo-js-optimization/<h2 id="introduction">Introduction</h2> <p>After <strong><a href="https://klikukliku.dev/posts/hugo-css-optimization">cleaning up CSS styles</a></strong> and <strong><a href="https://klikukliku.dev/posts/hugo-image-optimization">optimizing images</a></strong>, I focused on the JavaScript layer. At first glance, the situation looked innocent. The site was loading two files: a script from the theme and my own code for handling the color theme toggle. Together, they weighed less than three kilobytes. With such a small size, optimizing here might seem like overkill.</p> <p>However, the real challenge was hidden in the HTTP headers. I noticed that both files had a one-year cache lifetime. Unfortunately, their names lacked a unique identifier, or a &ldquo;fingerprint.&rdquo; This created a serious risk. It meant that after deploying any fixes, users would still use the old version of the code saved in their browsers.</p>