Roles they hire for
- CPU architecture and software engineer
- Trusted Firmware engineer
- Compiler and performance engineer
What they emphasise
- Architecture specifications and reference software
- Trusted Firmware-A and -M
- CMSIS and compiler toolchains
Brush up on
Armv8-M and Armv9TrustZoneException modelMemory orderingPerformance counters
How the rounds usually run
A typical silicon vendor loop for embedded roles. Companies vary by team and seniority.
Online assessment or screen
- C output prediction, pointers and bit manipulation
- Digital logic and OS basics
- For experienced hires, often a recruiter and hiring-manager screen instead
Example: What does this print: an unsigned char set to 200 plus 100, printed as an integer?
Technical 1: C and embedded fundamentals
- Pointers, volatile, const, alignment and endianness
- Interrupts, stacks and memory layout
- Live C coding on bit fields, ring buffers or string handling
Example: Implement a lock-free single-producer, single-consumer ring buffer.
Technical 2: Drivers and architecture
- Designing a peripheral driver and its API
- DMA, caches and interrupt priorities
- RTOS internals and debugging stories
Example: Design a SPI driver that supports blocking, interrupt and DMA modes behind one API.
Technical 3 or hiring manager: system design and projects
- Deep dive into a past project and your design choices
- System-level trade-offs: power, memory, performance
- Sometimes a short presentation on a project
Example: Walk through the hardest bug you've fixed, and what you changed in the process afterwards.
HR and behavioural
- Motivation, teamwork and conflict
- Relocation, notice period and compensation
Example: Tell me about a time you disagreed with a design decision.
Practice questions
Original questions written for Arm's focus areas, not leaked ones.
- Explain how TrustZone for Armv8-M separates secure and non-secure code, including how calls cross the boundary.
- What does a DMB guarantee that a DSB doesn't?
- How would you measure and reduce interrupt latency on a Cortex-M?
- Walk through what happens on a Cortex-M exception entry, including lazy floating-point stacking.
- How do you verify that a compiler optimisation is correct for all inputs?
Your prep playlist
Design rounds to practise
Themes are inferred from Arm's public product lines.
Take an AI mock round styled on Arm, with follow-ups that probe what you missed.
Start a mock round