Tests, TDD, and why testing matters now

Today Quincy Larson interviews Justin Searls. He's a software engineer who cofounded a software agency 15 years ago that's still going – even after he figured out how to make a lot of money quickly and retire at age 38 once he had enough savings.

These days he's gone from solving problems for client to solving solving problems for himself by building open source software. Often using emerging tools like agents. He says he getting way more done now than ever before.

We talk about: - How software development is ceasing to be a team sport and is now more about individual devs working directly for the people paying them - How verifiability is everything - whether it's agents contributing to your codebase or humans - How someone just now entering the field can use emerging tools to get an edge over more experienced developers

Note that I don't edit or censor these interviews at all. Justin uses some pretty blunt language so you may not want to listen to this around young children.

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Links from our discussion: - Justin's website: https://justin.searls.co - The Breaking Change podcast: https://justin.searls.co/casts - Justin's article "There's no AI in team": https://justin.searls.co/links/2025-08-03-there-is-no-ai-in-team/ - Justin's article about how software is supply-constrained: https://justin.searls.co/links/2025-11-04-software-is-supply-constrained-for-now/

Community news section:

1. freeCodeCamp just published a course that will take you deep into the modern Kubernetes ecosystem. You'll implement advanced industry standards such as Gateway API for traffic management, CloudNativePG for managing PostgreSQL databases, and cert-manager for automated HTTPS security. By the end of the course, you'll have the confidence to manage production-grade environments. (6 hour YouTube course): https://www.freecodecamp.org/news/master-kubernetes-through-production-ready-practice/

2. freeCodeCamp also published a comprehensive Notion course. It's not just a fancy notebook – you can use it as a full-blown operating system. You can code along at home and build your own task manager using Notion's "Software Legos" philosophy. Then you'll integrate your project with mail and calendar functionality, dashboards, and other advanced features. (12 hour YouTube course): https://www.freecodecamp.org/news/lean-notion-in-12-hours/

3. Learn how to guide agents to write secure code using a robust framework of rules and tests. Software engineer and recent podcast guest Sumit Saha shares his step-by-step process by building a Node.js shopping cart app using an agent. Instead of just using naive "one-shot" prompts, he leverages server-side validation and test-driven development. Well worth reading. (20 minute read): https://www.freecodecamp.org/news/how-to-guide-ai-with-rules-and-tests/

4. Learn the Python you need to know to build your own agents. This course starts by teaching you core Python syntax and best practices before moving on to NumPy, Pandas, and SQL. With these tools in your toolbelt, you can manage the data that fuels modern AI tools. (6 hour YouTube course): https://www.freecodecamp.org/news/learn-python-and-build-autonomous-agents/

5. Today's song of the week is from the UK band Unkle – 2003's hypnotic ballad "What Are You to Me?". The groove is mostly heald together by accoustic guitar and piano on top of layers of synth bass and breakbeats. We also get some Soulful, laid back feel from the featured vocalist, Joel Cadbury of the band South. This song just melts into the background. I think you're going to like it. https://www.youtube.com/watch?v=lgrN2uQKq9k