Evil Martians redesigned AppSignal's homepage by designing directly in code rather than relying solely on Figma, using LLMs (Claude) to accelerate development and maintain code conventions. The approach centered on jobs-to-be-done personas, bold opinionated copy, and interactive elements built from day one. An A/B test run via PostHog showed a 14% lift in activated users, +31% time on site, and +25% scroll depth, while signups stayed flat — indicating better-qualified visitors rather than more volume. The post details the workflow: iterating concepts in code, using a conventions file to guide Claude's output, and rolling the resulting design system across 80+ pages.
Table of contents
What the duck is going on with SaaS website design?An opinionated position serves as a self-qualifying lead pipelineMartian engineering perfects the AppSignal pageMeasurable outcomesWhen to consider designing in code?509 Impressions