The badge next to every code block on FlashReady now comes from a real compile — never from a version number someone typed.
What changed
- Every sketch is compiled automatically on the exact core and library versions shown on the page: ESP32 core 3.3.12, Arduino AVR 1.8.8, RP2040 6.3.1 and MicroPython (mpy-cross) 1.29.0. Today that’s 17 build targets, all passing.
- Nightly checks against the newest cores. If a new core release breaks a sketch, its page turns amber — “Needs update” — until we fix it.
- Honest test levels. “Compile-only” means exactly that. A page only says “Hardware-tested” after someone has run it on a real board.
- A real browser flasher. On /flash, Chrome and Edge can write firmware built from the same verified code straight to an ESP32 or ESP32-C3. Your browser checks every file’s SHA-256 before writing, and the board confirms each part afterwards. Saved settings on the board are left alone.
- A real Arduino Uno in your browser. The Playground now emulates the Uno and Nano for real — blink, buttons, an I2C LCD and the Serial Monitor all work.
Read the details on how we verify code.
What’s next
More board hubs, days 6–30 of the beginner path, Hindi translations, and hardware-tested badges as we work through the projects on our bench.