Roles they hire for
- ESP-IDF and driver engineer
- Wi-Fi and BLE stack engineer
What they emphasise
- ESP-IDF on FreeRTOS
- Wi-Fi and BLE stacks
- Flash encryption and secure boot
Brush up on
ESP-IDFFreeRTOS SMPWi-Fi provisioningFlash encryptionOTA partitions
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 Espressif's focus areas, not leaked ones.
- How does FreeRTOS SMP on a dual-core chip change how you protect shared data?
- Design Wi-Fi provisioning for a headless device.
- Explain flash encryption and secure boot together. What does each protect against?
- Design an OTA partition layout with rollback.
- Wi-Fi drops every few hours in the field. How do you investigate?
Your prep playlist
Design rounds to practise
Themes are inferred from Espressif's public product lines.
Take an AI mock round styled on Espressif, with follow-ups that probe what you missed.
Start a mock round