Summary: Linen is an open-source alternative to Slack and Discord that aims to merge the advantages of a forum with the real-time interaction of chat. The developers have reduced the bundle size of Linen to ~2MB parsed and ~500KB gzipped, which is half the size of the initial bundle. This reduction in bundle size has several benefits, including faster initial page load speed, improved search engine friendliness, and reduced security attack surface area. The developers used several optimization strategies, including fixing import issues and tree shaking problems, replacing libraries with custom code, and replacing heavy functions with custom functions. These strategies saved them ~600KB parsed and ~100KB gzipped.