Senior Frontend Engineer — Learning Path
A broad, autonomous engineer who owns features end-to-end with quality across the whole stack.
Level: Advanced · Required: 221 articles (~47.5 h) · Optional: 55 articles (~14.1 h)
Difficulty of required articles: Foundational 30 · Intermediate 152 · Advanced 39.
Follow the sections in order. Articles link into docs/; each shows its difficulty and estimated reading time. Full prerequisites for any article are in its domain's graph.json (see GRAPH.md).
Milestones
- Own a feature end-to-end: UI, state, data, tests, a11y
- Make deliberate rendering and state-architecture choices
- Meet performance, security, and accessibility bars by default
- Ship safely with CI, monitoring, and error tracking
- Raise the bar through reviews and refactoring
Expected skills
By completing the required articles you should be able to:
- Full-stack-of-frontend delivery with quality built in
- Sound state, data, and rendering architecture
- Performance, security, and accessibility as defaults
- Production operability and code stewardship
Required articles
JavaScript
- Lexical Scope · Foundational · 8 min
- Closures · Foundational · 8 min
- Hoisting & TDZ · Foundational · 8 min
- Block vs Function Scope · Foundational · 8 min
- Property Descriptors · Foundational · 8 min
- The Prototype Chain · Foundational · 8 min
- Inheritance Patterns · Foundational · 8 min
- Proxies & Reflect · Foundational · 8 min
- The Callback Model · Foundational · 8 min
- Promises · Foundational · 8 min
- async / await · Foundational · 8 min
- Cancellation & AbortController · Foundational · 11 min
- ES Modules · Foundational · 8 min
- Dynamic Import · Foundational · 8 min
- Module Resolution Semantics · Foundational · 11 min
TypeScript
- Structural Typing · Foundational · 8 min
- Assignability · Foundational · 8 min
- unknown, never & any · Foundational · 8 min
- Literal & Unit Types · Foundational · 8 min
- Unions & Intersections · Foundational · 8 min
- Generics · Foundational · 8 min
- Generic Constraints · Foundational · 8 min
- Indexed Access & keyof · Foundational · 8 min
- Type Inference · Foundational · 8 min
- Control-Flow Narrowing · Foundational · 8 min
- Type Guards & Predicates · Foundational · 8 min
- Discriminated Unions · Foundational · 8 min
- Branded & Nominal Types · Foundational · 8 min
- Exhaustiveness · Foundational · 8 min
- Illegal States Unrepresentable · Foundational · 11 min
React
- The Render Phase · Intermediate · 12 min
- Reconciliation & Diffing · Intermediate · 12 min
- Keys & List Reconciliation · Intermediate · 12 min
- The Commit Phase · Intermediate · 12 min
- useState · Intermediate · 12 min
- useReducer · Intermediate · 12 min
- The Rules of Hooks · Intermediate · 12 min
- State Batching & Updates · Intermediate · 12 min
- useEffect & Synchronization · Intermediate · 15 min
- useLayoutEffect · Intermediate · 12 min
- Effect Cleanup & Dependencies · Intermediate · 15 min
- Refs & useRef · Intermediate · 12 min
- Error Boundaries · Intermediate · 12 min
- Concurrent Rendering · Advanced · 16 min
- Transitions & useTransition · Advanced · 19 min
- useDeferredValue · Advanced · 16 min
- Suspense · Advanced · 16 min
- Server Components · Advanced · 16 min
- Server Actions · Advanced · 16 min
- The RSC Payload & Boundaries · Advanced · 19 min
- memo, useMemo, useCallback · Intermediate · 12 min
- Referential Stability · Intermediate · 12 min
- The React Compiler Model · Intermediate · 12 min
Rendering Architectures
- The CSR Model · Intermediate · 12 min
- The App Shell Pattern · Intermediate · 12 min
- Client-Side Data Loading · Intermediate · 12 min
- The SSR Model · Intermediate · 12 min
- Hydration · Intermediate · 12 min
- Selective & Progressive Hydration · Intermediate · 15 min
- Hydration Mismatches · Intermediate · 12 min
- Static Site Generation · Intermediate · 12 min
- Incremental Static Regeneration · Intermediate · 15 min
- On-Demand Revalidation · Intermediate · 12 min
- Streaming SSR · Advanced · 16 min
- Progressive Rendering & Flushing · Advanced · 19 min
- Out-of-Order Streaming · Advanced · 16 min
- The Server/Client Boundary · Intermediate · 12 min
- Islands Architecture · Intermediate · 12 min
- Resumability vs Hydration · Intermediate · 12 min
- Edge vs Origin Rendering · Intermediate · 12 min
State Management
- Categories of State · Intermediate · 12 min
- Server vs Client State · Intermediate · 12 min
- UI vs Domain State · Intermediate · 12 min
- Ephemeral vs Persistent State · Intermediate · 15 min
- Local State · Intermediate · 12 min
- Lifting State Up · Intermediate · 12 min
- Global State · Intermediate · 12 min
- Colocation vs Centralization · Intermediate · 15 min
- Computed Values · Intermediate · 12 min
- Selectors & Memoized Selectors · Intermediate · 15 min
- Store Shape & Normalization · Intermediate · 15 min
- The Reducer Pattern · Intermediate · 12 min
- Unidirectional Data Flow · Intermediate · 12 min
- Event Sourcing & Commands · Intermediate · 12 min
- Modeling UI with State Machines · Intermediate · 15 min
Data & Server State
- Fetch-on-Render vs Render-as-You-Fetch · Intermediate · 15 min
- Parallel vs Waterfall Requests · Intermediate · 15 min
- Request Deduplication · Intermediate · 12 min
- Data Prefetching · Intermediate · 12 min
- Cache Keys & Query Identity · Intermediate · 15 min
- Staleness & Revalidation · Intermediate · 12 min
- Cache Invalidation · Intermediate · 12 min
- Background Refetching · Intermediate · 12 min
- Mutation Lifecycle · Intermediate · 12 min
- Optimistic Updates · Intermediate · 12 min
- Rollback & Conflict Resolution · Intermediate · 15 min
- Pagination · Intermediate · 12 min
- Infinite & Cursor Loading · Intermediate · 12 min
- List Virtualization · Intermediate · 12 min
- Normalizing Server Responses · Intermediate · 15 min
- Client-Side Relations · Intermediate · 12 min
- Derived Server Data · Intermediate · 12 min
- Retries & Backoff · Intermediate · 12 min
- Loading & Error States · Intermediate · 12 min
- Offline & Local-First Sync · Intermediate · 12 min
Routing
- Route Matching & Params · Intermediate · 12 min
- Nested Routes & Layouts · Intermediate · 12 min
- Parallel & Intercepting Routes · Intermediate · 15 min
- The URL as State · Intermediate · 12 min
- Route Loaders & Dependencies · Intermediate · 15 min
- Deferred & Streaming Route Data · Intermediate · 15 min
- Route Actions & Mutations · Intermediate · 12 min
- Navigation & Linking · Intermediate · 12 min
- Transitions & Pending UI · Intermediate · 12 min
- Scroll Restoration · Intermediate · 12 min
- Route Prefetching · Intermediate · 12 min
Component & Interaction Design
- Prop Design & Contracts · Intermediate · 12 min
- Composition vs Configuration · Intermediate · 15 min
- Polymorphic Components (as) · Intermediate · 15 min
- Slots & Children APIs · Intermediate · 12 min
- Headless Components · Intermediate · 12 min
- Controlled vs Uncontrolled Pattern · Intermediate · 15 min
- Compound Components · Intermediate · 12 min
- Render Props · Intermediate · 12 min
- Pointer & Mouse Interaction · Intermediate · 15 min
- Drag & Drop · Intermediate · 12 min
- Hover, Press & Long-Press States · Intermediate · 15 min
- Gesture Handling · Intermediate · 12 min
- Loading & Skeleton States · Intermediate · 12 min
- Empty States · Intermediate · 12 min
- Error & Retry States · Intermediate · 12 min
- Disabled & Busy States · Intermediate · 12 min
Frontend Architecture
- Separation of Concerns · Intermediate · 12 min
- Layered Architecture · Intermediate · 12 min
- Module Boundaries · Intermediate · 12 min
- Dependency Direction & Inversion · Intermediate · 15 min
- Feature-Based Structure · Intermediate · 12 min
- Domain-Driven Frontend · Intermediate · 12 min
- Colocation Principles · Intermediate · 12 min
- Rendering Boundaries · Intermediate · 12 min
- Data-Fetching Boundaries · Intermediate · 12 min
- Client/Server Split · Intermediate · 12 min
Performance Engineering
- Core Web Vitals (LCP, INP, CLS) · Intermediate · 15 min
- Perceived vs Actual Performance · Intermediate · 15 min
- Custom Performance Metrics · Intermediate · 12 min
- Lab vs Field Measurement · Intermediate · 12 min
- The Critical Rendering Path · Intermediate · 15 min
- Code Splitting · Intermediate · 12 min
- Resource Prefetch & Preload · Intermediate · 15 min
- Critical CSS & Above-the-Fold · Intermediate · 15 min
- Font & Asset Loading Strategy · Intermediate · 15 min
- Rendering Cost & Re-renders · Intermediate · 15 min
- Long Tasks & Main-Thread Work · Intermediate · 15 min
- Debounce, Throttle & Scheduling · Intermediate · 15 min
- Offloading to Workers · Intermediate · 12 min
- Performance Budgets · Intermediate · 12 min
- Regression Prevention & CI Gates · Intermediate · 15 min
- Caching for Performance (cross-layer) · Intermediate · 15 min
Security
- Same-Origin Policy · Advanced · 16 min
- CORS · Advanced · 16 min
- Isolation (COOP/COEP) · Advanced · 16 min
- Cross-Site Scripting (XSS) · Advanced · 16 min
- DOM-Based XSS · Advanced · 16 min
- HTML/Template Injection · Advanced · 16 min
- Sanitization & Encoding · Advanced · 16 min
- Session Management · Advanced · 16 min
- Token Types (JWT, opaque) · Advanced · 16 min
- Token Storage Trade-offs · Advanced · 16 min
- OAuth & OIDC Flows · Advanced · 16 min
- Client Auth (guards, refresh) · Advanced · 19 min
Testing & Quality
- The Testing Pyramid/Trophy · Intermediate · 12 min
- What to Test & Coverage Goals · Intermediate · 15 min
- Test Doubles (mocks, stubs, fakes) · Intermediate · 15 min
- Rendering & Querying · Intermediate · 12 min
- User-Event Simulation · Intermediate · 12 min
- Accessibility-Tree Assertions · Intermediate · 15 min
- Testing with Real Providers · Intermediate · 15 min
- Network Mocking · Intermediate · 12 min
- Testing State & Data Flows · Intermediate · 12 min
- E2E User Flows · Intermediate · 12 min
- Cross-Browser Testing · Intermediate · 12 min
- Visual Regression Testing · Intermediate · 12 min
Accessibility
- WCAG Principles (POUR) · Intermediate · 12 min
- Conformance Levels · Intermediate · 12 min
- The ARIA Model · Intermediate · 12 min
- Accessible Name Computation · Intermediate · 15 min
- Keyboard Navigation · Intermediate · 12 min
- Focus Management · Intermediate · 12 min
- Focus Order & Tab Trapping · Intermediate · 12 min
- Skip Links & Landmarks · Intermediate · 12 min
- WAI-ARIA Widget Patterns · Intermediate · 12 min
- Accessible Forms · Intermediate · 12 min
- Live Regions & Announcements · Intermediate · 15 min
Developer Experience & Workflow
- Monorepo Architecture · Intermediate · 12 min
- Task Orchestration & Pipelines · Intermediate · 15 min
- Workspace Dependency Graphs · Intermediate · 15 min
- Remote Caching & Affected Builds · Intermediate · 15 min
- Linting · Intermediate · 12 min
- Formatting · Intermediate · 12 min
- Type Checking in CI · Intermediate · 12 min
- CI Pipeline Design · Intermediate · 12 min
- Build & Test Automation · Intermediate · 12 min
- Deployment Automation · Intermediate · 12 min
- Pipeline Caching & Speed · Intermediate · 12 min
Observability & Reliability
- Client Error Capture · Advanced · 16 min
- Source Maps & Symbolication · Advanced · 19 min
- Error Grouping & Alerting · Advanced · 16 min
- RUM & Field Vitals · Advanced · 16 min
- Session Replay · Advanced · 16 min
- Sampling Strategies · Advanced · 16 min
Engineering Practices
- Naming · Advanced · 16 min
- Function & Module Size · Advanced · 16 min
- Comments & Intent · Advanced · 16 min
- Refactoring · Advanced · 16 min
- Managing Technical Debt · Advanced · 16 min
- Legacy Code Strategy · Advanced · 16 min
- Code Review as a Discipline · Advanced · 19 min
- Giving & Receiving Feedback · Advanced · 19 min
- Error-Handling Philosophy · Advanced · 16 min
- Defensive vs Offensive Programming · Advanced · 19 min
- Graceful Degradation · Advanced · 16 min
Optional articles
API Design & Contracts
- REST · Advanced · 16 min
- GraphQL · Advanced · 16 min
- RPC · Advanced · 16 min
- Realtime & Subscriptions · Advanced · 16 min
- Resource & Schema Design · Advanced · 16 min
- Versioning Strategies · Advanced · 16 min
- Pagination & Filtering Conventions · Advanced · 19 min
- Error Contract Design · Advanced · 16 min
- End-to-End Type Safety (tRPC) · Advanced · 19 min
- Code Generation from Schemas · Advanced · 19 min
- Contract Testing · Advanced · 16 min
- Backend-for-Frontend · Advanced · 16 min
- API Gateways & Aggregation · Advanced · 16 min
- Response Shaping · Advanced · 16 min
Build Systems & Tooling
- The Dependency Graph · Intermediate · 12 min
- Bundler Models · Intermediate · 12 min
- Entry Points & Output · Intermediate · 12 min
- Transpilation & Targets · Advanced · 16 min
- Source-to-Source Compilers · Advanced · 16 min
- AST Transforms & Plugins · Advanced · 16 min
- Tree Shaking · Intermediate · 12 min
- Dead Code Elimination · Intermediate · 12 min
- Chunking & Split Points · Intermediate · 12 min
- Scope Hoisting · Intermediate · 12 min
- Source Maps · Intermediate · 12 min
- Hot Module Replacement · Intermediate · 12 min
- Dev Server Architecture · Intermediate · 12 min
- Incremental Builds · Advanced · 16 min
- Persistent & Remote Cache · Advanced · 16 min
- Cache Invalidation Keys · Advanced · 16 min
Design Systems
- Token Architecture · Intermediate · 12 min
- Semantic Token Layers · Intermediate · 12 min
- Token Transformation & Distribution · Intermediate · 15 min
- Light/Dark & Color Modes · Intermediate · 12 min
- Multi-Brand Theming · Intermediate · 12 min
- Runtime vs Build-Time Theming · Intermediate · 15 min
Progressive & Cross-Platform Web
- The Service Worker Lifecycle · Advanced · 19 min
- Fetch Interception · Advanced · 16 min
- Update & Activation Strategy · Advanced · 19 min
- Runtime Caching Strategies · Advanced · 16 min
- Precaching & Offline Shell · Advanced · 16 min
- Background Sync · Advanced · 16 min
- Cache Versioning & Cleanup · Advanced · 16 min
- Web App Manifest · Advanced · 16 min
- Install Prompts & Criteria · Advanced · 16 min
- Standalone & Display Modes · Advanced · 16 min
- Push Notifications · Advanced · 16 min
- Badging & Periodic Sync · Advanced · 16 min
- Web Views & Hybrid Apps · Advanced · 16 min
- Wrapper Models (Capacitor) · Advanced · 16 min
- Web-to-Native Bridges · Advanced · 16 min
Delivery & Infrastructure
- Deployment Strategies (canary, blue-green) · Advanced · 19 min
- Rollbacks & Kill Switches · Advanced · 16 min
- Feature Flags · Advanced · 16 min
- Progressive Delivery & Experiments · Advanced · 19 min