Most devs are obsessed with Technical Debt. But there’s a silent killer that’s far more expensive: Knowledge Debt. 🧵 If you don't understand how your app works, you're building a "Black Box." Here is how AI can either save you—or sink you. open.substack.com/pub/javil/p/...

A developer is not a manual laborer in a digital factory. We aren't here to just carry out instructions without question. We are the navigators of complexity and the keepers of history. When we simplify our job to just "writing code," we lose what it matters. javil.substack.com/p/whats-the-...

Is your codebase an asset or a liability? Many teams mistake "Rewriting" for "Refactoring." One is a wrecking ball that pauses your business; the other is the engine of sustainable growth. 🚀 How to refactor "mercilessly" without breaking the system?. javil.substack.com/p/illusion-o...

Un poco sobre arquitectura evolutiva en software www.thoughtworks.com/es-es/insigh...

"Every generation rediscovers Waterfall." 🌊 AI promises complex systems in seconds, but at a cost: we lose the causal chain of learning. From Einstein to the Halting Problem, here is why learning needs time: javil.substack.com/p/causality-... 📖 #AI #SoftwareEngineering #Causality #Learning

Timeouts aren't a failure state—they’re an "Unknown State." Most developers think a timeout means "nothing happened." But in distributed systems, it often just means the client hung up while the server kept working. This is the Ghost Operation problem. javil.substack.com/p/timeouts?r...

Post: javil.substack.com/p/fundamenta...

Stop treating Interfaces as boilerplate. Use them as Strategic Boundaries: 🛡️ Quarantine the "Infrastructure Virus" 🔪 Create Seams for Legacy Code ⏳ Defer implementation to reduce cognitive load 🚀 Decouple Release from Deployment Full story: open.substack.com/pub/javil/p/...

The law of leaky abstractions is the reason why your solutions with AI does not work in the long run. open.substack.com/pub/javil/p/...

One of the key aspects of the development of a product is knowing where we should go from an architectural point of view. But why, when and how to create an architectural vision? open.substack.com/pub/javil/p/...

Sobre los sensible defaults de Thoughtworks www.thoughtworks.com/es-es/insigh...

Pull Request != Code Review javapro.io/wp-content/u...

🧠 AI is not solving software’s intrinsic problems — it’s amplifying them. Many believed coding was the only challenge in software. Others blamed human imperfection. But the truth is: software has intrinsic problems that even the best AI can’t fix. javil.substack.com/p/the-intrin...

A broken pipeline isn't just an annoyance, it's a signal. The true measure of a strong culture isn't whether your pipeline ever fails, but how fast you fix it. Do it quickly: Detect it, Fix it, Anticipate frequent errors locally How does your team handle a broken pipeline? lnkd.in/dUvtPTRd

Tests are fitness functions that warn us about unintentional behaviors we have introduced when changing some parts of the code, breaking old behaviors. Instead of testing the structure, test behaviors. javil.substack.com/p/dont-test-...

Las herramientas de mocking facilitan la creación de stubs, spies y mocks. Cuando empiezas a aprender a hacer tests, te encantan, después de un tiempo las odias y después te das cuenta de que vuelven a ser geniales. javil.substack.com/p/mocking-li...

Mistakes in software are opportunities to learn, but it's incredibly stupid to commit a mistake twice. open.substack.com/pub/javil/p/...

En este episodio de Hablando del de Thoughtworks, hablamos con Raffaella Roviglioni, Principal Experience Designer en Thoughtworks Italia, sobre cómo el Product Discovery puede marcar la diferencia entre construir por intuición o por comprensión real. www.thoughtworks.com/es-ec/insigh...

¿Ha pensado en la anatomía de un fallo en cascada en software? javi-kata.medium.com/cascading-fa...

¿Es posible construir software sin caer en la sobreingeniería? Hablamos con María Martínez Miralles sobre uno de los grandes desafíos del desarrollo moderno: la complejidad. Desde diferenciar la complejidad esencial de la accidental hasta hacerlo todo "bien". www.thoughtworks.com/es-es/insigh...

The 28th of April in Spain, the whole country was under a power outage. The way the system was restarted, remembered me about the dog-pile effect. javi-kata.medium.com/dog-pile-eff...

I exported all my medium articles to substack. I will also publish there apart from medium. substack.com/@javilopez1

You’ve probably heard this phrase, “We’ll refactor it later”, what do you feel with that?. Some people don’t trust this statement, so they don’t believe in that promise at all. And what do you think are the underlying reasons of this feeling? javi-kata.medium.com/how-to-use-t...

When I ask my mother about the recipe to do anything she makes, her answer usually is just taste it and decide from that. She is able to do things, receive feedback from her craft, react and change. Can we do the same when coding? javi-kata.medium.com/how-does-my-...

Design is a word that we use to mention the abstract properties inherent to a product, in hardware this usually means to think in design before creating the product. But is software a different beast?. javi-kata.medium.com/how-much-upf...

Tests are live documentation and as documentation tests need to show the relevant details and to hide the irrelevant details. We want to avoid “the trees won’t let us see the forest” effect. medium.com/gitconnected...

You cannot test everything with unit tests, and it’s a bad idea in general to test everything with higher level tests. So, how to find what to test with what?. levelup.gitconnected.com/when-i-use-i...

How to teach/learn trunk based development? levelup.gitconnected.com/how-to-teach...

Let’s use some simple refactors and the “expand and contract” method to understand how you can do a big breaking change (change an API, interface, etc.) in small backward compatible increments. levelup.gitconnected.com/expand-and-c...

How can we work in legacy code in small steps and pushing to main frequently?. Let’s discuss Golden Master technique. medium.com/gitconnected...

En este podcast de la serie "Hablando de Software" de Thoughtworks conversamos con @rgv.bsky.social, Tech Lead & Tech Coach, y @culoextremo.bsky.social, Senior Software Engineer en Voxel, sobre la industria del videojuego y el desarrollo de software. www.thoughtworks.com/es-es/insigh...

How to add a new feature and deploy frequently (every 5 minutes to prod)?. We can use toggles and branch by abstraction. medium.com/gitconnected...

I love TDD now, but when I started practicing I thought this was not for me, the majority of people who hate TDD think as I thought at the beginning of my journey, what did I discover to continue?. medium.com/gitconnected...

Melvin Edward Conway submitted in 1967 a paper called “How Do Committees Invent?” to the Harvard Business Review. HBR rejected it on the grounds that Melvin had not proved his thesis, it was published later in Datamation. medium.com/gitconnected...

We tend to talk about this is good, this is bad when we talk about engineering practices, principles, designs, etc. In software everything is a trade-off, we need to understand what’s working best for the context we are working on. levelup.gitconnected.com/the-elephant...

In someway or other in your company, there is a way to change things that are hard to change. The usual thing is having a committee of architects or similar roles who approve that change. That committee is a centralized way to change things. medium.com/gitconnected...

Change is the only constant in software, and we can change tests, but we should treat tests more as sacred cows than code. At the end, they are the guardians of the behaviors of our application. javi-kata.medium.com/tests-are-cl...

There are a lot of people whose first and unique relation with code reviews is through pull requests. So they think this is the only way to do it, no, it is not levelup.gitconnected.com/code-review-...

The LSP is one of the lesser known SOLID principles, but in my opinion, it is crucial to create good types and subtypes. medium.com/gitconnected...

Mocks are easy to use and help us to design easily, but we should not use them to mock things we cannot change. medium.com/gitconnected...

Inside software teams, we can have different stakeholders that want new feature. All of them ask for a change and wait until the team is able to do it or try to push individuals? medium.com/gitconnected...

Software engineering should be to use the best techniques and practices to solve a problem that our customers have in the easiest and cheaper possible way. What do you think is going to make us succeed or to fail?. medium.com/@javi-kata/t...

The beginning or the end of the year is usually full of 1:1s with managers talking about devs performance. But how is this info collected, how much feedback sessions do you usually have, just with managers, just top-down? medium.com/gitconnected...

There are a lot of words in Software Development that have lost their original meaning, we have adapted them to convince ourselves that we are doing the right thing. medium.com/gitconnected...

A team with a 100% of utilization is a useless software team. medium.com/gitconnected...

Different parts of the system done by different people in parallel that need to be integrated will have problems when the integration is happening because “the devil is in the details”. medium.com/@javi-kata/t...

Code smells in software are a tool to understand that something could be a problem in the future, because change is the only constant in software. But smells are not problems you have to fix 100% of times, even perhaps it’s better to wait a while before trying to fix it. medium.com/gitconnected...