LowFile-scopeJavaScript / TypeScript Plug & play

Memoize components and callbacks when props are stable

For pure functions called repeatedly with the same inputs, memoize results; avoid recreating identical callbacks in hot paths.

Why this matters

Reduces redundant computation and churn.

Side-by-side examples engineers can pattern-match during review.

Avoid

list.forEach(x => expensive(x));

Prefer

const memo=(fn)=>{const m=new Map();return (x)=>m.has(x)?m.get(x):(m.set(x,fn(x)),m.get(x))}; const f=memo(expensive); list.forEach(f);

Bad

arr.map(expensive)

Good

const f=memo(expensive); arr.map(f)

From the same buckets as this rule.

Critical
Avoid Blocking Calls to Async Methods
Blocking async methods with `.Result` or `.Wait()` can cause deadlocks and prevent efficient asynchronous execution. Use `await` instead for proper async behavior.
concurrency-safetyperformance-efficiency
Critical
Fingerprint assets and cache immutably
All static JS/CSS/font/image files MUST use content-hashed filenames (e.g., app.9c1a7b.js) and be served with "Cache-Control: public, max-age=31536000, immutable". HTML and other non-fingerprinted documents MUST be served with "Cache-Control: no-cache" (or equivalent) to enable conditional revalidation.
web-static-assetscaching-strategy+2
Critical
No live network or DB in unit tests—use fakes/mocks
Unit tests must stub or fake external HTTP/DB calls; allow real I/O only in integration/e2e tests tagged accordingly.
testing-qualityperformance-efficiency+1