Articles on programming, AI agents, online business and entrepreneurial mindset. All from the trenches, building real products.
Weeks using Claude Code with mediocre results. Then I changed one thing about how I prompted it and the difference was massive. It's not the model. It's you talking to it like it's a search engine.
The people I know who 'guard their secrets' are in the exact same place they were three years ago. The ones who share everything keep moving forward. It's not a coincidence: scarcity mindset doesn't protect you, it paralyzes you. Here's why shifting that mental model is the most important strategic decision you can make in 2026.
Selling a VPN has a brutal contradiction at its core: almost every marketing tool you'd use to grow violates exactly what you're promising your user. Here's how I solved it in Nautilus VPN, commit by commit.
Most builders choose their LLM by inertia or by what they read on Twitter. But building profitable AI agents in 2026 requires something more specific: choosing the right model based on task type, not hype. Here's the framework I use.
Most indie hackers don't lose time building — they lose it integrating tools nobody designed to work together. In 2026 there's an 8-tool stack that covers everything from database to social automation, frictionlessly and without rewrites. Here's the complete architecture, with the concrete patterns that make the difference.
Most entrepreneurs fill out the WADM matrix with the weights they think they have. The problem: there's a brutal gap between what you say you value and what you actually weight when evaluating an idea. This article shows you how to spot that gap before it costs you months.
Most people use Claude like a generic assistant. But there's a whole layer—Skills—that transforms Claude into an expert for your specific workflow, loading procedural knowledge on-demand with a 3-level architecture built for efficiency. Here's how it works and how to build your own.
There's a book on financial mindset that most people ignore because the title sounds like an empty promise. But inside is a framework that completely reorders how you think about money, time, and business. Here's what I found.
Building an emergency plumber directory is easy. Building one you can actually trust at 2am with a burst pipe is a different story. Here's the logic behind find-emergency-plumber.com's quality system, and what you can learn to vet service providers yourself.
Mailchimp took 20+ years to reach its massive Intuit acquisition, with founders retaining 100% ownership. It wasn't luck—it was NRR, Rule of 40, and expansion revenue. Here are the real numbers that separate SaaS companies worth a fortune from those barely surviving.
Most developers build 'agents' that are, at their core, API calls with some conditional logic wrapped around them. Claude Agent SDK in 2026 proposes something fundamentally different: systems that gather context, act, verify their own work, and repeat the cycle autonomously. Here are the 4 concrete patterns that make that difference.
Most builders analyze failed projects after they die. The Pre-Mortem inverts that logic: you imagine the project has already failed, before you even start. The result is counterintuitive but powerful: more failure causes are identified than with any other planning technique.
CCL Guadalajara is not a SaaS, generates no leads, and has no conversion metrics to report. And that's exactly why it was one of the most useful projects I've built in 2026: it forced me to design software for users who are not developers. Here's what I learned.
The average physical business operates on margins of just 2.8-3.5%, while a digital course can hit 85-95%. But the real difference isn't in monthly profit—it's in what your company is worth the day you decide to exit. Here's the math that completely changes how you should think about what you build.
I had 2,163 CNAE/IAE codes to cover and zero time to do it manually. The solution was a multi-agent system with Claude that orchestrates filtering, planning, writing, publishing, and social distribution autonomously. Here's how it's built, decision by decision.
34% of online businesses fail because they build something nobody wants. But there's a second, equally silent mistake: building something anyone can already do. MJ DeMarco's CENTS framework has a direct answer for this—and most entrepreneurs don't apply it until it's too late.
Supabase Edge Functions isn't just 'another way to write serverless'. With the Deno 2.1 runtime, dashboard-native testing, and a generous free tier, it fundamentally changes how you ship backend logic without leaving the ecosystem. Here's the real case, with code.
Howard Marks built one of the world's largest investment firms with a single edge: thinking differently—and better—than everyone else. This week, after covering Munger and Naval, I close the trilogy with the framework that's most changed how I evaluate every product decision.
Conversor IAE CNAE started completely free. With 2,247 dynamically generated pages and real SEO traffic, the uncomfortable question arrived: how do you generate revenue without destroying what made the product useful? Here's the real monetization architecture I built: three layers, zero paid advertising, and the technical decisions behind each one.
34% of startups fail because they build something nobody wants. But there's a public, free, and brutally honest data point that predicts whether your market has real buying intent before you write a single line of code: CPC. Here's how to read it correctly.
Most developers see Cloudflare as a cheaper AWS alternative. They're looking in the wrong direction. The real difference isn't in cost — it's in the V8 isolate architecture that makes your product literally faster than competitors who pay more. Here's why in 2026 this is no longer optional.
Most people optimize for effort. Naval Ravikant has been saying for years that's exactly the mistake. Judgment—not hustle—is what separates those who build wealth from those who merely accumulate hours. Here's the complete framework and how to apply it in 2026.
When I started building Gestorías Cerca de Mí, the first thing I did was analyze what already existed in the market. What I found was surprising: it's not that directories don't exist, it's that they all make exactly the same mistakes. Here's the full analysis and the technical decisions I made to build something different.
Building from scratch isn't the only path to a profitable online business. A mature acquisition market exists where current multiples are near historic lows, creating a real window for buyers. The problem is most people don't know how to read the right signals or choose the right platform for their profile.
Daltix went from managing EC2 servers to scaling to 5 million resources per day while cutting infrastructure costs by 90%. It wasn't magic — it was switching to the right tool at the right time. Here's when that switch makes sense and how Apify works under the hood.
Charlie Munger had a strange rule: before forming any opinion, he had to be able to argue the opposing side better than its own advocates. Few people pass that test. Here's why that changes everything, and how to apply it to your decisions as a builder.
Everyone tells you that you can't compete with NordVPN or ExpressVPN. And they're right... if you try to be them. NautilusVPN was born from a different question: what niche are the giants ignoring? This is the build, the real technical decisions, and what it means to launch a SaaS in a market that seems impossible.
Vercel Hobby and Cloudflare Free together form one of the most powerful stacks you can build without spending a cent. But there's an SSL configuration mistake that catches almost everyone on their first attempt, and limits you need to know before launching anything serious. Here's everything, with the exact DNS records and the fix nobody documents properly.
Everyone tells you to set better goals. Nobody tells you that goals might be the problem. Donella Meadows spent decades studying complex systems and found something uncomfortable: most of us push change in exactly the wrong direction.
The WADM Matrix is a brilliant tool for evaluating business ideas, until it becomes a trap for postponing decisions. In 2026, the real skill isn't knowing how to use the framework: it's knowing when to ignore it.
November 2024. Anthropic quietly launched MCP. Now in 2026, there are 270+ servers in production and companies like Block and Apollo use it in their stacks. The problem: most tutorials only teach you one of the protocol's three primitives. Here you'll see all three, with real Python code.
I spent months deploying functions on Vercel without truly understanding the difference between Edge and Serverless. When I finally got it, it changed how I structure every project. Here's exactly what they are, when to use each, and how to make that decision before writing your first line of code.
It's not about generosity or strategy. Entrepreneurs who win long-term are literally running a different mental operating system—one that processes failure, competition, and time in radically different ways. In 2026, with more noise than ever, understanding these three mental patterns is the most underestimated competitive advantage.
The AI agent market grows at 45.3% annually with projections reaching $103.6B by 2032. Everyone talks about text chatbots. But there's a category growing even faster, with less competition, and barely anyone in Spain is touching it: voice agents.
Every Next.js developer thinks they understand Vercel's pricing until the first bill arrives. The problem isn't the price—it's that nobody explains the five metrics that actually control what you pay, and which one completely changes the game for AI workloads in 2026.
There's a brutal difference between a regular plumbing lead and an emergency one at 3 AM. It's not a volume difference—it's an urgency difference. And that urgency changes absolutely everything: the price, the technical architecture, and the business strategy behind find-emergency-plumber.
Most SaaS founders obsessed with acquiring new customers are ignoring the number that determines whether their business is worth a fortune or almost nothing: Net Revenue Retention. The difference between being above or below 90% isn't linear. It's abysmal.
Most devs use Resend for simple transactional emails and stop there. But when I started building a bulk notification system, I discovered it has a completely different batch architecture — with limits, superpowers, and traps nobody explains. Here's what I learned from the trenches.
There are three roads to wealth. Intelligent pessimism—that voice that sounds like prudence—is exactly what pushes the most capable people toward the slowest path. The Millionaire Fastlane explains it better than any other book I've read in 2026.
Your Stripe integration isn't done when the first payment goes through. There are two silent holes bleeding your MRR from day one: failed payments you never recover and users who churn because they can't manage their own subscription. Here's how to close both with Smart Retries and the Customer Portal.
Over 15 frameworks exist to compress decades of wisdom into repeatable processes. Most people use none of them. These three transformed military strategy, massive-scale corporate decisions, and zero-to-one technological innovation.
Thousands of freelancers and SMEs in Spain operate with incorrect IAE or CNAE codes without realizing it, losing access to grants and risking penalties from the tax authority. In this article I explain the real difference between both systems, the most common classification errors, and how to use a converter to ensure your business is correctly registered in 2026.
Online courses operate at 85-95% margins while physical retail barely hits 2.8-3.5%. That 30x gap isn't just an accounting detail—it's why two entrepreneurs with the same effort can end up in completely different economic worlds. Here's the structure behind that gap.
I just found out Buffer has no public API. None at all. While searching for an alternative, I found Late: an API that publishes to 12 platforms with a single POST call, offers full API access free from day one, and has delivered over 2.3 million posts with 99.97% uptime. This changes how I build content tools.
Howard Marks isn't just a legendary investor: he's the best teacher of cyclical patterns in existence. In 2026, while everyone debates whether AI is a bubble or a real takeoff, his framework on inevitable cycles answers exactly when to act and when to wait. And it applies equally to markets and products.
Most local directories are designed for Google's crawler, not for the human who needs to find a gestoría in 2 minutes. In this article I share the specific UX decisions I made in Gestorías Cerca de Mí to serve both, and why some of those decisions go completely against what you'd do if you were only thinking about SEO.
Everyone validates whether their idea will sell in month one. Nobody validates whether it will still be selling in year ten. There are two completely different types of validation, and confusing them is why only 34.9% of businesses survive a decade.
Sanity's free tier is genuinely generous, but most developers don't know exactly when they need to upgrade. Here's what I learned building real projects: a personal SaaS, a client project, and a team content platform.
Naval Ravikant has a mental trick that isn't about money—it's about clarity. It's about setting an hourly rate so high it embarrasses you... and then using it as a filter for every decision in your day. I applied it for months and it changed everything.
For weeks I haven't manually written a single article for conversoriaecnae.es. A multi-agent system with Claude does it for me: filters sources, plans topics, generates articles, scores quality, and auto-publishes if they pass the threshold. Here's how it works under the hood and the technical decisions that make it sustainable.