Session 160-75 min
Repair the Incident Controls
Diagnose state that drifts from a live incident list and repair it without hiding the underlying cause.
mediumReact StateDebuggingDerived StateImmutability
Codstak Pro · $15/month
14-session React Interview Prep
A practical progression for mid-to-senior frontend interviews: diagnose real React problems, build resilient UI behavior, and finish with a capstone you can explain.
Self-paced. Complete the 14 sessions on your own schedule.
What you’ll practice
The complete 14-session progression.
Foundations / debugging
Session 275-90 min
Design a Reusable Filter Menu
Turn a one-off filter strip into a reusable, controlled component API without losing accessible semantics.
mediumComponent ApiCompositionControlled ComponentsAccessibility
Product behavior
Session 390-110 min
Build an Accessible Command Picker
Implement a composite listbox with predictable keyboard focus and selection behavior.
hardAccessibilityKeyboardComposite WidgetReact
Session 490-110 min
Make Customer Search Race-Safe
Handle loading, empty, error, cancellation, and stale responses in an async customer search.
hardAsyncAbort ControllerRacesError Handling
Session 5100-120 min
Build a Validated Deployment Request
Implement a two-step deployment workflow with field validation, review, and recoverable submission.
mediumFormsValidationWorkflowAccessibility
Session 6100-120 min
Build a Typed Release Explorer
Create a typed, sortable, filterable release interface without duplicating server data into view state.
mediumTypescriptData GridSortingDerived State
Advanced engineering
Session 790-110 min
Test a Subscription Status Interface
Add behavior-focused tests to a subscription status interface with loading, error, upgrade, and renewal states.
mediumTestingAccessibilityBehaviorReact Testing Library
Session 890-110 min
Investigate a Render Budget
Diagnose unnecessary rerenders in a searchable incident list and optimize only where measurement supports it.
hardPerformanceMemoizationProfilingReact
Session 9100-120 min
Model a Refund Workflow
Use a reducer to model an explicit refund workflow with valid transitions and recoverable errors.
mediumReducerState MachineWorkflowError Recovery
Session 10100-120 min
Recover an Optimistic Preference Update
Implement an optimistic notification-preference update that isolates pending work and restores failed changes.
hardOptimistic UiRecoveryAsync StateAccessibility
Session 11100-120 min
Debug Browser Boundaries Safely
Repair storage and cross-window event handling without trusting stale or unverified browser data.
mediumBrowserStorageEventsSecurity
Session 1290-120 min
Scalable Notification Center
Design and implement the state, data, and component boundaries for a resilient notification center.
hardArchitectureServer StateOptimistic UiAccessibility
Capstone / assessment
Session 13150-210 min
Triage Lane
Build a resilient support-operations queue from an intentionally incomplete product brief.
hardCapstoneAsync StateOptimistic UiAccessibility
Session 1490-120 min
Triage Lane: Review and Explain
Review your submitted Triage Lane capstone, strengthen it, and prepare to explain its trade-offs.
hardCapstoneReviewTestingAccessibility
Final capstone
Triage Lane
Build a realistic support-operations queue with async loading, retry and cancellation, search and filtering, case selection, optimistic updates, rollback, accessibility, and architecture decisions.
Session 14
Review, refactor, and explain your own capstone.
Start from your submitted project, improve tests, fix a weakness, refactor a design issue, and explain the architecture and tradeoffs behind it.
Program outcome
An evidence-based readiness summary.
After the capstone review, Pro learners receive evidence for what is strong and what needs more practice—not a fake readiness percentage.
CorrectnessReact patternsAccessibilityEdge casesTestingArchitectureTradeoff explanation
Each area is reported as Strong evidence, Developing, or Needs more practice.
Free preview
Try Session 3: Build an Accessible Command Picker.
Experience the multi-file workspace, keyboard interaction, focus management, and browser verification before upgrading. The other 13 sessions, capstone workspaces, and readiness outcome remain part of Pro.
Quick actions
Command picker
Selected: Search workspace