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explore / Web & frontend / mozg / React Router

React Router · Guides

Answer how-to questions about React Router and the reasoning behind its design: the how-to recipes, the explanation pages on data loading and state, and the upgrade guides from v6 and Remix.

499 notes · updated 2026-08-09 · trained 96%

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$ claude mcp add --transport http mozg \
https://mozg.sh/mcp --header "Authorization: Bearer …"
> use mozg/react-router-guides — …
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Ask it things like

answers 29/30 on its latest exam
What does useFetcher do differently from normal navigation?Concurrency & Navigation✓
When I load data in a loader, what structure must I return if I have multiple pieces of data?Data Loading✓
What does HydrateFallback do and when is it used?Hydration & Server Rendering✓
Where should logout be performed in a React Router app—in the loader or action?Sessions & Cookies✓
What's the minimum version I should upgrade to before upgrading from React Router v6 to v8?Architecture & Upgrade✓
What does the future.v8_splitRouteModules flag do, and do I need to change my code to enable it?Code Splitting & Hot Reload✓
What's a critical rule for function components if I want React Fast Refresh to work properly?Code Splitting & Hot Reload✓
When I have multiple concurrent form submissions, when does React Router commit data to the page?Concurrency & Navigation✓

What it can answer

30 coverage checks
96%
Answers 29 of the exam's 30 questions
▲Data Loading5 / 6
✓Code Splitting & Hot Reload4 / 4
✓Concurrency & Navigation4 / 4
✓State Management4 / 4
✓Error Handling3 / 3
✓Hydration & Server Rendering3 / 3
✓Sessions & Cookies3 / 3
✓Routing Essentials2 / 2
✓Architecture & Upgrade1 / 1
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Attacks survived

re-run weekly · 2026-08-10
✓gate-battery12/12 known hostile payloads caught by the ingest gate
✓injection-corpusevery active note scanned — no steering language
✓secret-corpusevery active note scanned — no keys or credentials

heuristic scans against known attack classes — measured and dated, not a promise of unpoisonability

Inside

  • future.v8_passThroughRequests passes raw HTTP request instance · data-loading
  • Migrate Vite SSR configuration to per-environment config · architecture
  • Enable future.v8_middleware in Data mode · architecture
  • Enable future.v8_middleware in Framework mode · architecture
  • future.v8_splitRouteModules requires no code changes · code-splitting
  • Enable future.v8_viteEnvironmentApi · architecture
  • Update to latest v7.x before upgrading to v8 · architecture
  • React Router v8 minimum versions · architecture
  • future.v8_middleware flag enables request/response middleware · architecture
  • Middleware context parameter changes in v8 · architecture
  • future.v8_splitRouteModules enables independent chunk loading · code-splitting
  • Enable future.v8_splitRouteModules · code-splitting
  • future.v8_viteEnvironmentApi enables experimental Vite Environment API · architecture
  • Enable future.v8_passThroughRequests · data-loading

Licence

CC BY-NC-SA 4.0

Use it, copy it, build on it, with credit. Selling it is not allowed.