Mastra react-best-practices

React performance optimization guidelines from Mastra Engineering. This skill should be used when writing, reviewing, or refactoring React code to ensure optimal performance patterns. Triggers on tasks involving React components, data fetching, bundle optimization, or performance improvements.

install

source · Clone the upstream repo

git clone https://github.com/mastra-ai/mastra

Claude Code · Install into ~/.claude/skills/

T=$(mktemp -d) && git clone --depth=1 https://github.com/mastra-ai/mastra "$T" && mkdir -p ~/.claude/skills && cp -r "$T/.claude/skills/react-best-practices" ~/.claude/skills/mastra-ai-mastra-react-best-practices && rm -rf "$T"

manifest: .claude/skills/react-best-practices/SKILL.md

source content

React Best Practices

Overview

Comprehensive performance optimization guide for React applications, containing 12 rules across 6 categories. Rules are prioritized by impact to guide automated refactoring and code generation.

When to Apply

Reference these guidelines when:

Writing new React components
Implementing data fetching
Reviewing code for performance issues
Refactoring existing React code
Optimizing bundle size or load times

Priority-Ordered Guidelines

Rules are prioritized by impact:

Priority	Category	Impact
1	Eliminating Waterfalls	CRITICAL
2	Bundle Size Optimization	CRITICAL
3	Client-Side Data Fetching	MEDIUM-HIGH
4	Re-render Optimization	MEDIUM
5	Rendering Performance	MEDIUM
6	JavaScript Performance	LOW-MEDIUM

Quick Reference

Critical Patterns (Apply First)

Eliminate Waterfalls:

Use
```
Promise.all()
```
for independent async operations (
```
async-parallel
```
)

Reduce Bundle Size:

Avoid barrel file imports, import directly from source (
```
bundle-barrel-imports
```
)
Defer non-critical third-party libraries (
```
bundle-defer-third-party
```
)

Medium-Impact Patterns

Client-Side Data Fetching:

Use Tanstack Query for automatic request deduplication (
```
client-request-dedupe
```
)

Re-render Optimization:

Use lazy state initialization for expensive values (
```
rerender-lazy-state-init
```
)
Apply
```
startTransition
```
for non-urgent updates (
```
rerender-transitions
```
)

Minimize

useEffect

function calls (

rerender-useeffect-function-calls

)

Rendering Patterns

Animate SVG wrappers, not SVG elements directly (
```
rendering-animate-svg-wrapper
```
)

Use

content-visibility: auto

for long lists (

rendering-content-visibility

)

JavaScript Patterns

Use Set/Map for repeated lookups (
```
js-set-map-lookups
```
)
Use
```
toSorted()
```
instead of
```
sort()
```
for immutability (
```
js-tosorted-immutable
```
)
Early length check for array comparisons (
```
js-length-check-first
```
)

References

Full documentation with code examples is available in:

references/react-best-practices-reference.md

- Complete guide with all patterns

```
references/rules/
```
- Individual rule files organized by category

To look up a specific pattern, grep the rules directory:

grep -l "Promise.all" references/rules/
grep -l "barrel" references/rules/
grep -l "Tanstack" references/rules/

Rule Categories in

references/rules/

```
async-*
```
- Waterfall elimination (1 rule)
```
bundle-*
```
- Bundle size optimization (2 rules)
```
client-*
```
- Client-side data fetching (1 rule)
```
rerender-*
```
- Re-render optimization (3 rules)
```
rendering-*
```
- DOM rendering performance (2 rules)
```
js-*
```
- JavaScript micro-optimizations (3 rules)