Gustavo Fonseca

Performance Marketing · AI · Dev

Building
sharper.

Brazil · London · Malaga

I'm Gustavo. Over 20 years running performance marketing for some of the world's biggest brands. I care about the work that actually moves things: stronger results, sharper teams, cleaner strategy. I write about what I learn along the way, now from a beach in Málaga.

Performance

What actually moves the number. Not the vanity metrics, not the pretty report. The decision that changes next month.

AI

Less noise, more signal. Where it genuinely changes outcomes and where it is just process dressed up as progress.

Building Things

What you learn when you have to make it work yourself. The part nobody writes about until after it ships.

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Anthropic Is Publicly Inviting Criticism. That Is a Brand Strategy

Anthropic Is Publicly Inviting Criticism. That Is a Brand Strategy

Anthropic launched a public campaign asking people for their hardest questions about AI, including the uncomfortable ones. Here's why that works as brand positioning and what it takes to copy it honestly.

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Anthropic Just Opened Up Its AI Adoption Data. Use It for Audience Research

Anthropic Just Opened Up Its AI Adoption Data. Use It for Audience Research

The Anthropic Economic Index is now a Claude connector you can query in plain English. Here's how I would use occupation and region level AI adoption data for positioning, targeting and content.

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Frontier AI Just Got Cheaper. Here's What That Does to Marketing

Frontier AI Just Got Cheaper. Here's What That Does to Marketing

Anthropic released Claude Sonnet 5 at near frontier performance for a fraction of the cost. Here's what falling AI prices actually change in a marketing operation and what your business should do about it.

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SEO vs AEO vs GEO: Why They Are Not the Same Thing

SEO vs AEO vs GEO: Why They Are Not the Same Thing

SEO, AEO and GEO are three different jobs. Here is what each one actually does, where they overlap, and how to spread your effort across all three in 2026.

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Claude Design Launches. Here's What It Means for Marketing Teams.

Claude Design Launches. Here's What It Means for Marketing Teams.

Anthropic released Claude Design, a visual creation tool that generates brand-matched designs from your team's codebase. Here's what I think it changes and what your business should do with it.

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Why Google Ads Still Wins (And What AI Gets Wrong About It)

Why Google Ads Still Wins (And What AI Gets Wrong About It)

AI tools are good at Google Ads execution and poor at strategy. Here's the three questions every advertiser needs to answer before touching the account, and why they matter more now.

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