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Tag: app-router

10
Sep 04 2026

revalidatePath is brute force, revalidateTag is precision

I confused revalidatePath with revalidateTag on a small project and ended up invalidating pages that had nothing to do with the change. Here's the real difference between the two cache granularities in Next.js 16, with a decision checklist.

Sep 04 2026 · 7′ · Tutorials · Next.js · React

7′
Aug 17 2026

Server Actions Solves Your Mutation, Not Your Cache

Server Actions in Next.js 16 App Router makes mutations dead simple without writing an endpoint. But when you need client-side cache, optimistic revalidation, or reactive data shared across components, that's where Server Actions falls short — and TanStack Query steps in to solve that, not to replace it.

Aug 17 2026 · 8′ · Tutorials · TypeScript · app-router

8′
Aug 14 2026

tsconfig paths in Next.js 16 App Router: when they help and when they silently break the build

Path aliases look innocent until the production build fails with no clear message. I documented the 3 most common breakage cases in a monorepo with Next.js 16 App Router and strict TypeScript, and the config pattern that survived.

Aug 14 2026 · 9′ · Tutorials · TypeScript · pnpm

9′
Jun 22 2026

Rate limiting in Next.js: what to protect before picking a library

Rate limiting isn't an npm dependency — it's an abuse policy. Before copying middleware, you need to define what asset you're protecting, what abuse pattern you expect, and what a false positive costs you. A guide with a decision matrix, real gotchas, and observability for Next.js.

Jun 22 2026 · 9′ · Tutorials · TypeScript · nextjs

9′
Jun 17 2026

OpenTelemetry in Next.js: traces that survive the edge/server boundary without losing context

OpenTelemetry in Next.js works, but the default propagator silently breaks the trace at the edge/node boundary. Here's what you need to configure explicitly so context doesn't vanish between Middleware, Server Components, and Server Actions.

Jun 17 2026 · 8′ · Tutorials · TypeScript · nextjs

8′
Jun 09 2026

React 19 Server Components and caching: the mental model I was missing after reading the docs

This isn't another RSC tutorial. It's the conceptual map I built after reading the official docs and understanding why the folklore around 'always use use client' is wrong — and what actually happens when you put Server Components in a real layout with dynamic data.

Jun 09 2026 · 9′ · Tutorials · TypeScript · nextjs

9′
Jun 04 2026

Next.js 16 Middleware: authorization patterns that scale and the ones that cause race conditions

I tested 4 authorization patterns in Next.js 16 Middleware with edge runtime. One causes silent race conditions, another gives you unexpected latency, and only one scales without compromises. Here's the honest tradeoff analysis of each.

Jun 04 2026 · 9′ · Tutorials · TypeScript · nextjs

9′
May 25 2026

export const revalidate = 0 in Next.js App Router: what it actually does

export const revalidate = 0 makes a Next.js App Router segment dynamic, forcing it to fetch fresh data on every request instead of serving from the Full Route Cache. Here's what it actually does, how it differs from no-store and force-dynamic, and how to decide which one your data actually needs.

May 25 2026 · 8′ · Tutorials · React · TypeScript

8′
May 18 2026

Prisma Server Actions in Next.js 16: the patterns that work and the N+1 that sneaks up on you

Prisma in Next.js 16 Server Actions has an N+1 vector that doesn't exist in classic API routes. The culprit isn't the ORM — it's how Actions compose. Here are the patterns that prevent it.

May 18 2026 · 7′ · Experiments · TypeScript · Performance

7′

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  • TypeScript in production
  • Security and operations
  • Agents and LLMs with judgment

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  • Tutorials93
  • Opinion44
  • Reflections18
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Tags

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  • #LLM
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Popular

  1. 01pnpm vs npm vs yarn vs bun: The Real Comparison Nobody Gives You in 2025
  2. 02Next.js App Router: The Guide I Wish I Had When I Migrated from Pages Router
  3. 03TypeScript: The Patterns I Actually Use Every Single Day
  4. 04Docker for Node.js Developers: From Zero to Production Without Losing Your Mind
  5. 05Your Digital Signing Cryptography Has an Expiration Date: What NIST Published and How to Migrate Your HSM

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Juanchi.dev is Juan Torchia’s public notebook — architecture, real systems and product decisions. Written and reviewed by hand in Buenos Aires. Built with Next.js, Prisma and PostgreSQL; deployed on Railway. No third-party trackers beyond aggregate analytics.

GitHubRSS© 2026 Juan Torchia · All rights reserved.

Real code. Unfiltered takes.

Architecture, real systems, product decisions and technical lessons. Everything reviewed with my own judgment before it ships.

230 articles published

Series

  • Open Data and Creativity2
  • Awesome Curated: The Tools11
  • Awesome Curated1
See all

Clusters

  • Software architecture
  • TypeScript in production
  • Security and operations
  • Agents and LLMs with judgment

Categories

  • Experiments99
  • Tutorials93
  • Opinion44
  • Reflections18
  • Technology8
  • History6

Tags

  • #TypeScript
  • #arquitectura
  • #nextjs
  • #railway
  • #java
  • #LLM
  • #postgresql
  • #ia
  • #prisma
  • #software-architecture
  • #firma-digital
  • #AI

Popular

  1. 01pnpm vs npm vs yarn vs bun: The Real Comparison Nobody Gives You in 2025
  2. 02Next.js App Router: The Guide I Wish I Had When I Migrated from Pages Router
  3. 03TypeScript: The Patterns I Actually Use Every Single Day
  4. 04Docker for Node.js Developers: From Zero to Production Without Losing Your Mind
  5. 05Your Digital Signing Cryptography Has an Expiration Date: What NIST Published and How to Migrate Your HSM

Newsletter

One email a week. What I'm learning, building, and breaking.

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