Shopify is developing a new storefront theme that replaces its JSON-heavy Horizon theme with clean, HTML-centric code using its Liquid templating language. The redesign was driven by the needs of Shopify's AI assistant Sidekick, which now handles 25 million theme edits per year from 20% of merchants. The key insight is that AI agents benefit from the same code qualities humans do: readability, explicit contracts, and constructive feedback. The new theme has 93% fewer lines of code than Horizon and introduces composable block tags, typed parameters similar to React props, partial page updates, and standard event actions. Liquid also gains new syntax including Boolean expressions and future Tailwind CSS support. The broader takeaway is that optimizing for AI comprehension may push the industry back toward more human-readable code formats.
