Prior to the phone screen, there was a CoderPad assessment with slightly tricky questions. It wasn't too difficult if you know C inside out.

This assessment was offline, where they gave you about 90 minutes to complete. It really only takes about 30 minutes if you know your stuff.

After that, there were two phone screens, followed by an on-site interview.

The entire process was extremely slow, taking up to 1.5 months.

There's also a presentation (about anything technical) that you need to do in front of the interviewers as a group.

Write a SPI driver.

Then, assuming a certain hardware bug, write a workaround.

Describe how JTAG works under the hood (e.g., setting breakpoints).

Implement a ring buffer.

Implement malloc_aligned(size_t size, size_t alignment) where alignment is a power of 2.