How to: June 29, 2025
1. freeCodeCamp just published a new handbook on how to build your own custom Model Context Protocol (MCP) server. The entire MCP paradigm was just invented 7 months ago, so let me explain how it works. Before MCP, you needed to write custom connector code for each data source your LLM used – such as calendars, map APIs, and sensor data streams. Sure – tools like LangChain helped with this. But MCP makes things so much simpler. You just lay out how your data is structured. That way when an LLM connects, it can figure out how to get whatever data it needs all on its own. This MCP approach is an excellent complement to the Retrieval Augmented Generation technique developers were using last year. (full-length handbook): https://www.freecodecamp.org/news/how-to-build-a-custom-mcp-server-with-typescript-a-handbook-for-developers/

2. Many of the recent breakthroughs in AI tools have been thanks to the Transformer Architecture pioneered at Google. This course will teach you how Transformers work, and how they're evolving. You'll learn about Attention Mechanisms, Positional Encoding, Activation Functions, and Normalization. Transformers! More than meets the eye! (3 hour YouTube course): https://www.freecodecamp.org/news/learn-the-evolution-of-the-transformer-architecture-used-in-llms/

3. On this week's freeCodeCamp podcast I interview Kelly Vaughn. She's a software engineer who went from building apps for freelance clients to running her own full-blown developer agency. She shares tips for scaling up your business in your community and not burning yourself out in the process. (1 hour watch or listen in your favorite podcast app): https://www.freecodecamp.org/news/from-therapist-to-six-figure-freelance-dev-podcast-176/

4. Learn how to build your own embedded systems – from smart fridges to home security systems. freeCodeCamp just published a comprehensive handbook that will teach you Firmware Design from the ground up. You'll learn about the Sense-Process-Act cycle that governs the behavior of most devices. Then you'll learn about low-level system design and modern best practices. (full-length handbook): https://www.freecodecamp.org/news/learn-embedded-systems-firmware-basics-handbook-for-devs/

5. Finally, freeCodeCamp also published our first-ever course on the German language. Learn how to speak the native language of more than 100 million Europeans with this A1-level course for absolute beginners. You'll learn grammar, pronunciation, vocabulary, and a ton of common phrases you can use while traveling. (12 hour YouTube course): https://www.freecodecamp.org/news/learn-to-speak-german/

Quote of the Week: *"There’s a difference between freelancing and running an agency. Freelancing is a hustle. Running an agency is about systems, people, and risk."* — Software Engineer Kelly Vaughn on this week's freeCodeCamp podcast