Web & JavaScript
Next.js, React, Node and TypeScript - the errors, the caching model, and shipping fast front ends that actually work in production.
Sub-topics
Next.js
34App Router, server components and the framework-specific traps.
Rendering & Caching
13SSR, static vs dynamic, the cache that won't invalidate, and hydration mismatches.
React
19Components, state, effects and the re-render bugs everyone hits.
TypeScript & Tooling
7Types, module resolution, ESM/CJS and the config that fights you.
Build & Deploy
12Bundlers, lockfiles, monorepos and the gap between localhost and production.
41 articles · showing 1-9 (page 1 of 5)
CSP 'unsafe-inline' Is Not a Fix: Nonces That Work in Next.js
Adding 'unsafe-inline' to silence CSP violations turns the header into compliance theatre. Here is the per-request nonce setup for Next.js that keeps hydration working.
ERR_REQUIRE_ESM on Vercel but not locally: the Next.js 16.2 monorepo bug
Your Next.js build passes and the Vercel deploy 500s with ERR_REQUIRE_ESM. Here is the missing .next/package.json that causes it, and three workarounds that hold.
Storing JWTs in localStorage Turns Any XSS Into Account Takeover
Every JWT tutorial puts the token in localStorage. Here is what that costs when XSS lands, and the in-memory access token plus HttpOnly refresh cookie setup that replaces it.
Decoding minified React error #418, #423 and #425 in Next.js production
Production React ships numbers instead of messages. Here is the decoder, what each hydration code actually says, and why you can reproduce all of it locally.
Why next dev keeps eating memory, and what actually helps
The Next.js dev server climbing to an out-of-memory crash is not one bug with one fix. Here is how to find which of the four layers is growing, and the mitigations that work today.
JavaScript Heap Out of Memory on next build: Find the Real Cause
Raising --max-old-space-size hides the problem instead of fixing it. Three different build phases can exhaust the heap, and the last log line tells you which one you have.
Users Randomly Logged Out: Fixing next-auth Token Rotation
Auth.js refresh token rotation silently drops the rotated token in four distinct ways, and the popular workaround of disabling rotation is worse than the bug. Here is the real fix.
Next.js Hydration Failed: Find the Real Mismatch, Not the Suppress Flag
Hydration failed and the overlay will not say which element. Here is the diff technique that finds it, the five real causes, and why suppressHydrationWarning is not a fix.
Dynamic Code Evaluation Not Allowed in Edge Runtime: The Next.js Middleware Fix
Mongoose and jsonwebtoken break Next.js middleware with a dynamic code evaluation error that names no package. Here is the real cause and the fix for each version.