E.g. What I used before I had my own printer: https://i.materialise.com/en. Source: about 1 year ago

Https://i.materialise.com/en is the service I've used. Upload the stl I make in blender, and it quotes the price. Source: about 1 year ago

Not for the US, no. But a quick search should give you good enough sites e.g. https://i.materialise.com/en. Source: almost 2 years ago

i.materialise.com , I believe the formats used are .OBJ and .WRL. Source: about 2 years ago

I can recommend these guys for printing any material i.materialise. Source: over 2 years ago

For the ESP32 in read mode, we've successfully developed a project using PlatformIO that accepts the key during build time and stores it in memory. Source: 10 months ago

Check out Zephyr OS and Platform IO. Zephyr is part of the Linux foundation and has similarities to Linux with how it performs hardware abstraction (device tree). Platform IO integrates with other frameworks including mbed and Arduino. Source: 10 months ago

PlatformIO together with avr-stub can be used to do source level debugging but there are some caveats. Source: about 1 year ago

Look into https://platformio.org/, it can abstract over a few RTOSes, and can show you which OSes work with which chips/boards. Source: about 1 year ago

If the HW looks like it works, you could also try alternate programming software. (e.g. TinyGo or PlatformIO). Source: about 1 year ago