How we brought HTTPS Everywhere to the cloud (part 1)

This post details the implementation of Automatic HTTPS Rewrites, a server-side solution to address mixed content issues by rewriting HTTP sub-resource links to HTTPS. It explains the limitations of naive approaches and browser extensions, and describes the use of Ragel to compile HTTPS Everywhere rulesets into a high-performance C state machine for efficient processing at the Cloudflare edge. The post also discusses optimizations for handling domain wildcards, particularly left-side wildcards, by reversing rules for more efficient state machine generation.