Career roadmap
Embedded & IoT Engineer
Write software that runs on hardware you can hold, with no operating system to hide behind and no easy way to patch it.
Before you start Embedded / IoT
- C fundamentals, or willingness to learn them properly
- Basic electronics: voltage, current, digital signals
- A development board and a cheap logic analyser
C and the machine
Embedded work demands understanding memory and hardware at a level web development never requires.
Still the dominant language, and interviews test it in detail.
- Pointers, arrays and pointer arithmetic
- Structs, unions and bitfields
- volatile, const and their real meanings
- Undefined behaviour and why it bites
No garbage collector, often no heap, and very little RAM.
- Stack, heap and static allocation
- Why dynamic allocation is often banned
- Memory maps and linker scripts
- Stack overflow detection
The chip is the platform. Its datasheet is the documentation.
- ARM Cortex-M architecture
- Registers, peripherals and memory-mapped IO
- Clock trees and power domains
- Reading a datasheet and reference manual
The source of the most subtle bugs in embedded systems.
- Interrupt service routines and latency
- Priorities, nesting and masking
- Race conditions and critical sections
- Timers and precise timing
No console. Debugging is done with hardware.
- Cross-compilation and linking
- JTAG/SWD debugging
- Logic analysers and oscilloscopes
- Reading a disassembly
BuildBlink an LED without a framework, by writing directly to registers, and explain every line.
Peripherals and protocols
Talking to the physical world through the interfaces every board provides.
The basics that every board and every interview starts with.
- GPIO configuration and pull resistors
- ADC and DAC operation
- PWM for control and dimming
- Debouncing and signal conditioning
I2C, SPI and UART cover the overwhelming majority of sensor communication.
- UART framing and baud rates
- I2C addressing, clock stretching and pitfalls
- SPI modes and chip select
- Debugging buses with a logic analyser
Turning a datasheet into working, testable code.
- Driver structure and abstraction
- Blocking versus interrupt-driven versus DMA
- Error handling on flaky hardware
- Portability across MCUs
Moving data without the CPU, which is how throughput is achieved.
- DMA controllers and channels
- Double buffering
- Cache coherency issues
- Measuring CPU load
Battery life is a headline product requirement in most IoT devices.
- Sleep modes and wake sources
- Duty cycling strategies
- Measuring current consumption
- Peripheral power management
BuildInterface three different sensors over three different buses, with a driver you wrote yourself.
RTOS and system design
Once a system does more than one thing, you need real concurrency management.
FreeRTOS and Zephyr dominate. Scheduling behaviour is heavily interviewed.
- Tasks, scheduling and priorities
- Queues, semaphores and mutexes
- Priority inversion and inheritance
- Stack sizing per task
Hard real time means late is the same as wrong.
- Hard, firm and soft real time
- Worst case execution time
- Jitter and determinism
- Schedulability reasoning
Structure that survives five years of feature additions on the same chip.
- Layering and hardware abstraction
- State machines for device logic
- Event-driven designs
- Modularity for testability
Hard, often skipped, and a genuine differentiator when you can do it.
- Unit testing on host with hardware mocks
- Hardware-in-the-loop testing
- Automated test rigs
- Static analysis and MISRA
The other half of the industry: gateways, cameras and richer devices.
- Yocto and buildroot basics
- Device tree and kernel modules
- Boot process and init
- When Linux beats an MCU
BuildRewrite a bare-metal project on an RTOS with tasks, queues and a documented timing analysis.
Connectivity and fleet operations
The IoT half: devices that talk to a backend and can be updated in the field.
Choosing the radio is a product decision with long consequences.
- BLE: GATT, advertising and pairing
- WiFi provisioning and reconnection
- LoRaWAN and cellular for wide area
- Range, power and bandwidth trade-offs
Devices are unreliable clients on unreliable networks.
- MQTT and CoAP
- Store and forward on disconnection
- Device provisioning and identity
- Telemetry design and bandwidth cost
The capability that decides whether a field bug is expensive or catastrophic.
- Bootloaders and A/B partitions
- Update verification and signing
- Rollback on failed boot
- Staged rollout across a fleet
Regulation is arriving, and physical access changes the threat model entirely.
- Secure boot and chain of trust
- Key storage and secure elements
- Encrypted communication on constrained devices
- Physical attack surface and debug port lockdown
Operating thousands of devices you cannot physically reach.
- Remote diagnostics and logging
- Configuration management
- Health monitoring and alerting
- Field failure analysis
BuildConnect a device to a cloud backend with telemetry, remote configuration and working OTA updates.
Interview preparation
Embedded interviews go deep on C, memory, interrupts and debugging.
Pointer and bit manipulation questions are near-universal.
- Bit manipulation and register masks
- Pointer and array questions
- volatile and const correctness
- Spotting undefined behaviour
Interrupts, concurrency and timing, asked in scenario form.
- ISR design constraints
- Race condition identification
- Priority inversion scenarios
- Memory corruption diagnosis
Reading schematics and datasheets is part of the assessment.
- Interpreting a datasheet timing diagram
- Reading a schematic
- Choosing a bus for a requirement
- Debugging a non-responding peripheral
Design a device to a power, cost and timing budget.
- MCU and radio selection
- Power budget calculation
- Firmware architecture proposal
- Update and security strategy
Physical projects are unusually persuasive in this field.
- A working device with published firmware
- Schematics and a bill of materials
- A debugging write-up with scope traces
- Contributions to open hardware or RTOS projects
BuildA documented hardware project with schematics, firmware and a written debugging story.
Embedded / IoT tools on your CV
- C / C++
- ARM Cortex-M
- FreeRTOS / Zephyr
- STM32 / ESP32
- Logic analyser
- Oscilloscope
- PlatformIO
- MQTT
What Embedded / IoT employers ask to see
- A working hardware project with published firmware and schematics
- A driver you wrote from a datasheet
- An OTA update system with rollback demonstrated
- A debugging case study with logic analyser traces
Automotive, medical devices, industrial automation, consumer hardware and energy. Steady, less cyclical than web, and unusually resistant to offshoring because it needs physical access.
Content last reviewed 2026-08-31. Guidance only — no institute or paid placement is endorsed anywhere in this book.