Professional agentic AI, on the Claude platform.
Training for individual contributors and engineering teams.
Most people use AI assistance as a fancier autocomplete. Working with agents in production takes method: context, judgment and verification. That's what I teach.
✦ Claude Code
From zero to professional, one tip a day.
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My Claude Code workflow.
The skills, agents and instructions I use as a professional Software Engineer. It's called Craft, and it's a plugin you can install.
See the skillsTraining and consulting on the Claude platform.
AI First on the Claude platform
A working day with your team, online, on the Claude platform. More output without losing quality.
Agentic AI for companies
I assess how your team works and agentify the processes one or several agents can take on.
At FrontendLeap I teach you to build the professional Web with agentic AI and learning science.
FrontendLeapStop Claude Code asking for permission (without losing control)
Permission prompts in Claude Code don't go away with one setting. There are five levers (rules, modes, auto mode, the sandbox and bypass inside a container), and this guide puts them in the order that cuts the most prompts for the least risk.
Claude Code first steps: the fundamentals that don't expire
The Claude Code fundamentals that don't expire: install, sessions, context, quota, models, permissions. What you actually need to grasp on day 1.
AI: the joy of missing out on what doesn't matter
You can't keep up with AI, and you shouldn't try. The answer isn't resistance or passive acceptance: go all in, but deep on one thing instead of scattered.
Claude Code Agent View: managing parallel agents without leaving the terminal
I spent months managing many Claude Code agents by hand. Agent View now does it: my terminal-native workflow with Warp and Neovim, and the gaps I patch.
What is Claude Code: A Practitioner's Overview
What Claude Code actually is, explained by someone who uses it 12+ hours daily in production. No hype, real examples.
Claude Design is shutting down: how to keep using it from Claude Code
Claude Design leaves claude.ai/design on December 14. In Claude Code, /design already creates the design as an artifact; /design-sync and the MCP still point at the site that closes.
Claude Code keeps rereading the same file: cut the repeated tokens
Claude Code rereads a file that hasn't changed, and since v2.1.317 every reread enters the context whole: 21,842 tokens for a 44 KB file, every time. One command over your transcript tells you whether it happens to you.
Claude Code has skills you didn't install: how to remove them
Skills like `docx`, `pdf` or `xlsx` show up in your terminal without you installing them: Claude Code downloads them from your claude.ai account, plugins included. And their descriptions ride on every request.
Code Mode in Claude Code: turn it on and every request costs fewer tokens
Code Mode is Claude Code's experimental mode where Claude writes JavaScript to call its tools. It ships off: how to turn it on, how many tokens it saves, and what stops working while it's on.
Fable 5.2 effort in Claude Code: use high only for these tasks
Fable 5.2 effort: Claude Code starts it at medium, and the level you saved for Fable 5.1 doesn't carry over. Across 24 runs with hidden edge cases every level got everything right; high cost twice as much, xhigh seven times.
Hi, I'm Juan Andrés Núñez.
Senior Software Engineer specializing in agentic AI, professional educator and speaker. Over fifteen years building for the Web and teaching how to do it. Today I work with the Claude platform every day. Here I publish everything I learn.
The 51 essentials, as a guide.
One page per tip. Five chapters. What I actually use daily in production. No theory, no fluff.