React & Next.js debugging
Debug the failure modes that actually bite React apps: stale closures, re-render storms, hydration mismatches, Server Component boundaries, and broken data fetching.
36 guides
Debugging guides
Diagnosing useEffect Infinite Loops in React ApplicationsReact bugs · IntermediateReact Hydration Errors: Diagnosing Mismatches Between SSR and ClientReact bugs · IntermediateDiagnosing and Fixing Next.js Build FailuresNext.js · IntermediateDiagnosing React Context Unnecessary Re-renders Impacting PerformanceReact bugs · IntermediateReact setState Called but State Not Updating: Real Debugging StepsReact bugs · BeginnerReact.memo Fails to Prevent Re-render: Deep Props, Functions, and TrapsReact bugs · IntermediateDiagnosing 404s from Next.js API Routes That Should ExistNext.js · BeginnerNext.js Middleware Not Executing on Expected RoutesNext.js · IntermediateEnvironment Variable Undefined at Runtime in Next.js ProjectsNext.js · BeginnerDiagnosing ‘React Hook Called Conditionally’ in Function ComponentsReact bugs · BeginnerNext.js Image Component Fails to Optimize ImagesNext.js · IntermediateReact List Rendering: Diagnosing and Fixing Key Prop WarningsReact bugs · BeginnerNext.js Static Site Generation Build Failures: Diagnosing getStaticProps and getStaticPaths IssuesNext.js · IntermediateDiagnosing `ref.current` Is Null in ReactReact bugs · IntermediateDiagnosing and Resolving Next.js Server Action ErrorsNext.js · IntermediateDiagnosing React Router Infinite Redirect LoopsReact bugs · IntermediateReact Custom Hook Stale Closure State BugsReact bugs · AdvancedDiagnosing Next.js Dynamic Import SSR FailuresNext.js · IntermediateDebugging Next.js Streaming SSR: Stuck, Broken, or Incomplete StreamsNext.js · AdvancedDiagnosing Next.js Authentication Cookies Not Being SetNext.js · IntermediateDiagnosing React's Controlled vs. Uncontrolled Component WarningReact bugs · Beginnernext.js revalidatePath Not Refreshing Cache on Dynamic RoutesNext.js · IntermediateDiagnosing Next.js App Router Layout Not RenderingNext.js · IntermediateWhy Your React Error Boundary Isn’t Catching ErrorsReact bugs · IntermediateDiagnosing Next.js Custom Webpack Config FailuresNext.js · AdvancedDebugging React Lazy: 'Loading Chunk Failed' in Suspense Lazy ComponentsReact bugs · IntermediateNext.js Server Component Incorrectly Using Client HooksNext.js · AdvancedZustand Persist Middleware Not Saving or Loading StateReact bugs · IntermediateReact Query Not Refreshing Stale Data Despite InvalidationsReact bugs · Intermediate“Module Not Supported” Errors in Next.js Edge RuntimeNext.js · AdvancedReact Portal Allows Click Events to Bubble Outside Intended DOMReact bugs · AdvancedDiagnosing tRPC Procedure Errors in Next.js AppsNext.js · IntermediateApollo Client Cache Not Updating After Mutation: How to Force a Normalized Cache RefreshReact bugs · IntermediateDetached DOM Tree Memory Leak: Hunting Ghost Nodes in the BrowserFrontend · AdvancedIntersection Observer Callback Not Firing: Debugging Silent FailuresFrontend · IntermediateService Worker Serving Stale Cache: Diagnose and FixFrontend · Intermediate