Use when optimizing React or Next.js request waterfalls, bundle size, server rendering or client re-renders. Not for component API design; use vercel-composition-patterns.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Vercel React Best Practices
Comprehensive performance optimization guide for React and Next.js applications, maintained by Vercel. Contains 57 rules across 8 categories, prioritized by impact to guide automated refactoring and code generation.
## When to Apply
Reference these guidelines when:
- Writing new React components or Next.js pages
- Implementing data fetching (client or server-side)
- Reviewing code for performance issues
- Refactoring existing React/Next.js code
- Optimizing bundle size or load times
## Rule Categories by Priority
| Priority | Category | Impact | Prefix |
|----------|----------|--------|--------|
| 1 | Eliminating Waterfalls | CRITICAL | `async-` |
| 2 | Bundle Size Optimization | CRITICAL | `bundle-` |
| 3 | Server-Side Performance | HIGH | `server-` |
| 4 | Client-Side Data Fetching | MEDIUM-HIGH | `client-` |
| 5 | Re-render Optimization | MEDIUM | `rerender-` |
| 6 | Rendering Performance | MEDIUM | `rendering-` |
| 7 | JavaScript Performance | LOW-MEDIUM | `js-` |
| 8 | Advanced Patterns | LOW | `advanced-` |
## Quick Reference
### 1. Eliminating Waterfalls (CRITICAL)
- `async-defer-await` - Move await into branches where actually used
…
The line at the top of this page pins the label v1.0.0, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
A 17 of 17 checks passed. Fixed automatic checks with no AI involved, so the same checks give the same answer every run.
pass: Frontmatter block present
pass: Frontmatter declares a name
pass: Frontmatter declares a description
pass: Size between 200 bytes and 200 KB (6007 bytes)
pass: No zero-width or bidi control characters
pass: No instruction hidden inside an HTML comment
pass: No link to an exfiltration or paste host
pass: No credential-shaped string
pass: No instruction to send local credentials anywhere
pass: No text hidden with inline styles
pass: No prompt-injection phrasing
pass: No curl or wget piped into a shell
pass: No recursive delete of root, home or parent
pass: No instruction to read or print local credentials
pass: No base64 blob over 200 characters
pass: No link to a raw IP address
pass: No script tag
Source
GitHub
cratis/ai · 4 stars · license MIT · pushed 2026-11-04 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_6uufzxwj5xjmwet4
GET https://markdownregistry.com/api/v1/resolve?ref=cratis/ai/vercel-react-best-practices
GET https://markdownregistry.com/api/v1/blob/59a5b23f054b757e7761b35c026a6494d2485c46258c58c1059fdf0ec370863d
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
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…
cherryhq/cherry-studio · .agents/skills/vercel-react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
vercel-labs/agent-skills · skills/react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
zebbern/claude-code-guide · skills/react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
gronxb/hot-updater · .agents/skills/vercel-react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
fcakyon/claude-codex-settings · plugins/react-skills/skills/react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
coco-research/coco · skills/vercel-react-best-practices/SKILL.md · Pointer to the upstream skill for React and Next.js performance work (data fetching, bundle size, re-renders)…
asymmetric-al/core · .agents/skills/vercel-react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
julianromli/ai-skills · skills/react-best-practices/SKILL.md · React and Next.js performance optimization guidelines from Vercel Engineering. This skill should be used when writing…
