Laravel

Quick Reference

Critical Rules

• Eager load relationships — with('posts') not lazy ->posts in loop (N+1)
• preventLazyLoading() in dev AppServiceProvider — crashes on N+1, catches early
• env() only in config files — returns null after config:cache
• $fillable whitelist fields — $guarded = [] allows mass assignment attacks
• find() returns null — use findOrFail() to avoid null checks
• Job properties serialize models as ID — re-fetched on process, may be stale/deleted
• route:cache requires controller routes — closures break cached routes
• DB::transaction() doesn't catch exit/timeout — only exceptions roll back
• RefreshDatabase uses transactions — faster than DatabaseMigrations
• {!! $html !!} skips escaping — XSS vector, use {{ }} by default
• Middleware order matters — earlier middleware wraps later execution
• required validation passes empty string — use required|filled for content
• firstOrCreate persists immediately — firstOrNew returns unsaved model
• Route model binding uses id — override getRouteKeyName() for slug