Use only what is strictly necessary. No frameworks, no build tools, no package managers for frontend code. Every line of code must justify its existence.
Your folder structure is your URL structure. Drop a file in a folder and it's instantly accessible. No routes to configure, no databases to set up.
Custom templates and styles go in /custom/ and automatically override defaults. The core files in /app/default/ remain untouched and updateable.
Use modern PHP 8.3+ features and modern CSS capabilities. Avoid JavaScript entirely—it's not needed for content-focused sites.