DIY Electronics, Smart Projects, and Real-World Builds
J-Rat Techworks
I build practical, real-life projects using ESP32 boards, sensors, 3D printing, FreeCAD, Home Assistant, and whatever else I can get my hands on.
This site brings everything together in one place – code, wiring diagrams, parts lists, downloads, and full write-ups to make each project easier to follow.
Have a build you want to show off?
Send it through and I’ll feature my favourites on the site.
The Best Mini PC for Home Assistant in 2026
Finding the best mini PC for Home Assistant is not…
CN3791 MPPT Solar Li-ion/LiPo Charging Boards: what they are and how to use them safely
Quick Summary A CN3791 MPPT board is a small module…
ESP32-S3 in the real world: when it’s the right ESP32 (and when it isn’t)
Ever built a “simple” ESP32 project that almost works, until…
What You’ll Find Here
Step-by-Step Project Guides
Each project includes diagrams, code, troubleshooting notes, and all the parts you need. Every YouTube video has a matching page here.
Recommended Tools & Parts
The hardware and components I use the most, tested across real builds, not just listed for the sake of it.
Downloads & Files
STL files, PCB Gerbers, ESPHome YAMLs, Arduino sketches, and anything else used in my builds.
Behind-the-Scenes Notes
What worked, what didn’t, and the lessons learned while testing and breaking things along the way.
