What is route caching and performance in CodeIgniter 4?

CodeIgniter 4 does not have a separate route caching command like Laravel, but it has several performance features. The route optimization is handled through CI4's startup sequence. Enable Config caching to avoid re-parsing configuration on every request. The most significant performance feature is Auto-routing Improved (disabled by default) — when disabled, only explicitly defined routes are processed, which is faster and more secure. Use $routes->setPrioritize(true) for performance in large route files. Page caching: $this->cachePage(300) in a controller method caches the entire response as a static file for 300 seconds — extremely fast for pages that do not change frequently. Enable OPcache at the PHP level for significant performance gains by caching compiled PHP bytecode. For API-heavy applications, use Redis for response caching via CI4's Cache service.