Use when changing React concurrent rendering, Server Components, actions, hooks or re-render behavior. Not for Next.js routing and caching or React Hook Form field validation.
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What the file says
# React 19 Best Practices
Comprehensive performance optimization guide for React 19 applications. Contains 40 rules across 8 categories, prioritized by impact from critical (concurrent rendering, server components) to incremental (component patterns).
## Table of Contents
1. [Concurrent Rendering](references/_sections.md#1-concurrent-rendering) — **CRITICAL**
- 1.1 [Avoid Suspense Fallback Thrashing](references/conc-suspense-fallback.md) — HIGH (prevents flickering, smoother UX)
- 1.2 [Leverage Automatic Batching for Fewer Renders](references/conc-automatic-batching.md) — HIGH (32% fewer renders in heavy updates)
- 1.3 [Use useDeferredValue for Derived Expensive Values](references/conc-use-deferred-value.md) — CRITICAL (prevents jank in derived computations)
- 1.4 [Use useTransition for Non-Blocking Updates](references/conc-use-transition.md) — CRITICAL (keeps UI responsive during heavy updates)
- 1.5 [Write Concurrent-Safe Components](references/conc-concurrent-safe.md) — MEDIUM-HIGH (prevents bugs in concurrent rendering)
2. [Server Components](references/_sections.md#2-server-components) — **CRITICAL**
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Source
GitHub
cratis/ai · 4 stars · license MIT · pushed 2026-11-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_2m4nmouqbd2gm56a
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GET https://markdownregistry.com/api/v1/blob/b4088b6267a12372a958cd9102bf4494688e34fc20d2dcc41efbb2e668cb220f
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cratis/ai · .cratis/ai/skills/analyzing-dotnet-performance/SKILL.md · Use when reviewing .NET hot paths or scanning source for allocation-heavy and inefficient patterns. Not for measuring a…
cratis/ai · .cratis/ai/skills/binlog-generation/SKILL.md · Use when an MSBuild failure or performance investigation needs a binary log and none exists. Not for analyzing existing…
cratis/ai · .cratis/ai/skills/check-bin-obj-clash/SKILL.md · Use when multi-project or multi-targeted MSBuild builds collide in bin, obj or project.assets.json, overwrite outputs…
cratis/ai · .cratis/ai/skills/coverage-analysis/SKILL.md · Use when interpreting supplied .NET coverage evidence or an explicit coverage-collection request. Not for hypothetical…
cratis/ai · .cratis/ai/skills/cratis-application-react-specifications/SKILL.md · Write specifications for the React and TypeScript surface of a Cratis application slice — view models, helpers, command…
cratis/ai · .cratis/ai/skills/cratis-application-slice-conformance/SKILL.md · Reconcile a Cratis slice's hand-written or gap-filled code and specifications with its contract (the `.play` slice and…
cratis/ai · .cratis/ai/skills/cratis-application-slice-specifications/SKILL.md · Specify the backend behavior of an event-sourced Cratis application slice — plain-call specs for pure decisions, plus…
cratis/ai · .cratis/ai/skills/cratis-arc-authentication-authorization-and-identity/SKILL.md · Wire authentication, authorization and identity in a Cratis Arc application — IProvideIdentityDetails and the…
cratis/ai · .cratis/ai/skills/cratis-arc-command-execution/SKILL.md · Execute an existing Cratis Arc command from backend code through ICommandPipeline — the scopeless and scoped overloads…
cratis/ai · .cratis/ai/skills/cratis-arc-command-kotlin/SKILL.md · Define a Cratis Arc command in Kotlin or Java — the @Command class, its handle() method, the optional provide() step…
cratis/ai · .cratis/ai/skills/cratis-arc-command-operation/SKILL.md · Declare immediate inline work as a Cratis Arc ICommandOperation returned by a model-bound command, with optional…
ericrisco/rsc-harness · skills/react/SKILL.md · Use when building or reviewing a client-side React SPA bundled by Vite (React 19.2): components, where state lives…
magnus919/agent-skills · react/SKILL.md · Operate React applications as a named tool: inspect and diagnose React/Vite projects, design component boundaries and…
jnpiyush/agentx · .github/skills/languages/react/SKILL.md · Build React applications with modern hooks, TypeScript, and performance best practices. Use when creating React…
