# CodePress Developer The CodePress developer guide contains the following topics: - **Architecture** — CMS architecture and folder structure - **Core classes** — CodePressCMS, ThemeManager, PluginManager, AdminAuth - **Plugin development** — Plugin types (content/system), structure, API - **Routing** — Frontend, admin and plugin admin routing - **Security** — XSS, CSRF, path traversal, RBAC - **Testing** — Penetration, accessibility and functional tests - **Debugging** — Logging and cache - **Performance** — OPcache and SCSS caching Important concepts in CodePress 2.5.2: - **Plugin types** — Content plugins (sidebar) and system plugins (admin menu, routes, API) - **Admin plugin API** — System plugins can register admin menu items and routes - **SCSS compilation** — `ThemeManager` compiles SCSS to `css_compiled/` via scssphp (read-only) - **Asset serving** — `public/asset.php` serves themes/, admin/assets/ and plugins/ on Apache (instead of PHP dev router) Select a topic from the navigation on the left.