Juanchi.dev
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Juanchi.dev
Digital Native · real systems
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HomeCasesCVBlogLabContact

Software architecture

A pillar page that organizes posts about system design, legacy modernization, full stack decisions, and applied AI with production judgment.

  • Runtime decisions

    What actually changes when adopting new concurrency models and runtimes in existing systems.

  • Full stack architecture

    Next.js, backend, data, and clear boundaries between product, platform, and operations.

  • Applied AI with judgment

    Agents, models, and automation when they improve a real, auditable workflow.

Recommended reads

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Sep 16 2026

XGBoost Doesn't Beat scikit-learn, It Solves a Different Problem

With a small, reproducible dataset in Jupyter, I compare what XGBoost actually does differently from scikit-learn's RandomForest — and why the answer isn't "which one is better" but "which problem is this for."

Sep 16 2026 · 8′ · Tutorials · machine learning · python

8′
Sep 09 2026

Claude API Key Security: Why .env Is Not Optional

Pasting a Claude or DeepSeek API key straight into your code "just to test it quick" leaves a trail in your git history and your logs. A no-nonsense guide to environment variables, rotation, and what to check before sharing a repo.

Sep 09 2026 · 7′ · Tutorials · nextjs · anthropic

7′
Sep 05 2026

That messy 4000-line notebook taught me to stop hating Jupyter

Why Jupyter is still the de facto standard for exploring data, even though versioning it with git will make you want to smash your keyboard.

Sep 05 2026 · 5′ · Experiments · python · data science

5′
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′
Sep 03 2026

DeepSeek Reasonix: A Technical Read on a Native Coding Agent with Aggressive Caching

DeepSeek Reasonix shows up as a native coding agent with aggressive caching and low cost. Before you adopt it or dismiss it, there's a more useful question: what specific problem does it actually solve in a real stack, and what reproducible experiment confirms that?

Sep 03 2026 · 9′ · Opinion · LLM · ia

9′
Sep 02 2026

Cline on Autopilot: Why I Put Limits on My Agent

Cline lets you auto-approve every action the agent takes without asking permission. The button exists. The question is why, as an architect, I'd rather not touch it — and what hidden cost total autonomy has in a real codebase.

Sep 02 2026 · 7′ · Tutorials · AI agents · arquitectura de software

7′

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 with Coolify on a self-managed VPS. No third-party trackers beyond aggregate analytics.

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