1. What is an Embedded Engineer?

As an Embedded Engineer at Lyft, you sit at the critical intersection of hardware and software, powering the physical devices that connect the digital Lyft platform to the real world. While Lyft is widely known for its rideshare app, this role is pivotal in the Lyft Bikes & Scooters (micromobility) division and specialized hardware initiatives like the Lyft Amp (the dashboard indicator) and next-generation vehicle connectivity. You are not just writing code; you are breathing life into processors, sensors, and actuators that millions of people rely on for daily transportation.

In this role, you will design, implement, and debug firmware for battery-operated, connected devices. The work involves tight constraints—processing power, memory, and energy consumption must all be optimized to ensure reliability and longevity. You will work closely with Electrical Engineers to bring up new boards, with Backend Engineers to ensure seamless IoT connectivity, and with Product Managers to define how a user interacts with a scooter or bike.

This position offers a unique opportunity to work on high-volume consumer electronics that operate in harsh outdoor environments. Your code ensures that a scooter unlocks instantly when a user scans it, that GPS tracking is accurate even in urban canyons, and that safety-critical systems function flawlessly. For engineers who love seeing their code result in physical motion, this is one of the most impactful roles at Lyft.

2. Getting Ready for Your Interviews

Preparing for an interview at Lyft requires a shift in mindset from pure software to system-level thinking. You need to demonstrate not just how to write algorithms, but how those algorithms interact with bare-metal hardware and real-time constraints.

Key Evaluation Criteria:

Technical Proficiency in C/C++ – You must demonstrate mastery of C and C++ in resource-constrained environments. Interviewers will evaluate your understanding of memory management, pointers, bit manipulation, and how high-level code translates to assembly instructions.

Embedded System Architecture – Beyond coding, you are evaluated on your ability to design robust systems. You will be asked to make architectural decisions regarding RTOS vs. bare metal, inter-processor communication, power management strategies, and over-the-air (OTA) update mechanisms.

Hardware-Software Integration – You need to show that you can read a schematic and debug a system where the issue could be software, hardware, or physics. Interviewers look for candidates who understand peripheral interfaces (I2C, SPI, UART) and can discuss board bring-up processes.

Lyft Values & Collaboration – Lyft places a high premium on "making it happen" and "being yourself." You will be evaluated on your ability to communicate complex technical concepts to non-technical stakeholders and how you collaborate in a cross-functional team environment.

3. Interview Process Overview

The interview process for the Embedded Engineer role at Lyft is rigorous and structured to test both your depth in firmware and your breadth in system design. Generally, the process moves quickly, starting with a recruiter screen to align on your background and interests. This is followed by a technical phone screen, which typically involves a coding exercise focused on C/C++ fundamentals or a light system design discussion.

If you pass the initial screen, you will move to the virtual onsite loop. Based on recent candidate experiences, this loop is heavily weighted toward Design and Architecture. You should expect multiple rounds dedicated to designing an embedded system from the ground up. Unlike general software engineering roles that focus heavily on abstract algorithmic puzzles, the Embedded loop focuses on domain-specific challenges—concurrency, memory constraints, and hardware interfacing.

Lyft’s interviewing philosophy is practical and collaborative. Interviewers want to see how you think through a problem when the specifications are ambiguous. They are interested in your trade-off analysis: why did you choose a mutex over a semaphore? Why specifically that communication protocol? The goal is to simulate a real working session with a colleague.

The timeline above illustrates the typical flow from application to offer. Note the emphasis on the Onsite stage, which is where the deep technical dives occur. Use the time between the Technical Screen and the Onsite to practice whiteboard-style system design, as this is often the steepest hurdle for candidates.

4. Deep Dive into Evaluation Areas

To succeed, you must demonstrate deep expertise in the core pillars of embedded engineering. Use the following breakdown to structure your technical study.

Low-Level Coding & Algorithms

This area tests your raw coding ability in C and C++. You will not typically face dynamic programming graphs common in web roles; instead, expect questions that manipulate bits, bytes, and memory. Be ready to go over:

• Bit Manipulation – Setting, clearing, and toggling bits in registers.
• Memory Management – Stack vs. Heap, dynamic allocation dangers, and memory leaks.
• Pointers – Function pointers, volatile keyword usage, and pointer arithmetic.
• Advanced concepts – Writing your own malloc or memcpy implementation.

Example questions or scenarios:

• "Implement a function to reverse the bits in a byte."
• "Write a driver for a hypothetical sensor using memory-mapped I/O."
• "Detect a loop in a linked list (constrained memory context)."

Embedded System Design & Architecture

This is a critical component of the Lyft interview, often comprising two full rounds. You will be asked to architect a system relevant to Lyft's business, such as a bike lock or a scooter controller. Be ready to go over:

• System Partitioning – Deciding what tasks run on which processor or core.
• Power Management – Designing for battery life, sleep modes, and wake-up sources.
• Communication Protocols – Choosing between I2C, SPI, UART, CAN, or BLE based on throughput and power.
• Advanced concepts – OTA (Over-the-Air) update architecture and security (bootloaders).

Example questions or scenarios:

• "Design the electronics and firmware architecture for a smart bike lock."
• "How would you design a system to track a scooter's location and report it to the cloud periodically?"
• "Architect a safe firmware update process for a fleet of vehicles."

RTOS & Concurrency

Lyft devices often run Real-Time Operating Systems (RTOS). You need to understand how to manage multiple tasks without crashing the system. Be ready to go over:

• Synchronization Primitives – Mutexes, semaphores, queues, and event flags.
• Scheduling – Preemptive vs. cooperative scheduling, priority inversion, and starvation.
• Interrupt Handling – Writing efficient ISRs (Interrupt Service Routines) and deferring work.

Example questions or scenarios:

• "Explain priority inversion and how to prevent it."
• "How do you share data safely between an ISR and a main thread?"
• "Debug a scenario where the system hangs intermittently."

The word cloud above highlights the frequency of terms found in interview reports. Notice the prominence of "Design," "Architecture," "Bits," and "RTOS." This confirms that while coding is required, your ability to design a scalable and reliable system is the primary differentiator for this role.

5. Key Responsibilities

As an Embedded Engineer at Lyft, your day-to-day work is hands-on and varied. You are responsible for the entire firmware lifecycle, from initial board bring-up of prototype hardware to maintaining code that runs on thousands of devices in the field. You will spend significant time writing low-level drivers for sensors (accelerometers, GPS, cellular modems) and implementing application logic that manages the state of the vehicle.

Collaboration is a massive part of the job. You will work side-by-side with Electrical Engineers to debug noise on a bus or verify power consumption. You will also coordinate with Backend Engineers to define the API contract between the IoT device and the Lyft cloud, ensuring data is serialized efficiently to save data costs.

Project ownership is encouraged. You might lead an initiative to improve the GPS accuracy of the scooter fleet or reduce the standby power consumption of the bike lock. This involves not just coding, but measuring, testing in the lab, and analyzing field data to drive improvements.

6. Role Requirements & Qualifications

Candidates who succeed in this role typically possess a strong foundation in electrical engineering concepts alongside computer science fundamentals.

• Must-have Technical Skills:

  • Expert proficiency in C and C++.
  • Experience with RTOS (FreeRTOS, Zephyr, or similar) and multi-threaded programming.
  • Deep knowledge of communication protocols: I2C, SPI, UART, CAN, BLE.
  • Experience with Git and version control in a team setting.

• Experience Level:

  • Typically requires a BS or MS in Electrical Engineering, Computer Engineering, or Computer Science.
  • Usually 3+ years of industry experience working on shipping hardware products (consumer electronics, automotive, or robotics).

• Nice-to-have Skills:

  • Experience with wireless stacks (Bluetooth Low Energy, LTE-M, NB-IoT).
  • Knowledge of Python for scripting test tools and automation.
  • Background in motor control or battery management systems (BMS).

7. Common Interview Questions

The following questions are representative of what you might face. They are not a script, but rather a guide to the types of problems Lyft uses to evaluate engineering maturity.

Technical Coding & C Language

• "Explain the keyword volatile. When and why would you use it?"
• "Implement aligned_malloc and aligned_free. How do you handle memory alignment?"
• "Write a function to count the number of set bits in a 32-bit integer."
• "What is the difference between a macro and an inline function? When would you use one over the other?"
• "How would you implement a circular buffer in C?"

System Design & Architecture

• "Design a firmware architecture for a shared electric scooter. Include the major hardware components and software tasks."
• "We have a sensor that sends data via SPI. Design the driver and the data processing pipeline."
• "How would you handle an Over-the-Air (OTA) update if the battery dies in the middle of the process?"
• "Design a logging system for a device with very limited flash memory."

OS & Concurrency

• "You have two threads trying to access the same resource. How do you prevent a race condition?"
• "What is a deadlock? Draw a scenario where it happens and explain how to fix it."
• "Explain the difference between a mutex and a binary semaphore."
• "How does an interrupt service routine differ from a standard function call?"

8. Frequently Asked Questions

Q: How much hardware knowledge is required for this role? You are not expected to design the PCB, but you must be able to read a schematic, use an oscilloscope/logic analyzer, and understand the hardware limitations. You should know how to debug a problem to determine if it's a software bug or a hardware fault.

Q: Is the interview process mostly coding or mostly design? Recent experiences indicate a shift toward System Design and Architecture. While you will definitely write C code, the ability to architect a system is heavily weighted, especially for mid-level and senior roles.

Q: What specific microcontrollers does Lyft use? While specific stacks change, familiarity with ARM Cortex-M series (STM32, Nordic nRF, etc.) is the industry standard and highly relevant. Experience with any major microcontroller family is transferable.

Q: What is the work culture like for the hardware team? The hardware team (often based in San Francisco) is known for being collaborative and fast-paced. Because you are dealing with physical products, there is often a need to be in the office or lab for board bring-up, making this role more likely to be hybrid than fully remote.

9. Other General Tips

Know your protocols deep. Don't just say "I used I2C." Be ready to explain how the start/stop conditions work, how addressing is handled, and what happens during clock stretching. Lyft engineers value depth.

Clarify constraints immediately. In design questions, always ask about power sources (Battery? Mains?), connectivity (Always on? Intermittent?), and cost. These constraints fundamentally change your design, and asking them shows seniority.

Practice "Whiteboard" Coding in C. You are likely used to an IDE with autocomplete. Practice writing syntactically correct C code on a blank sheet of paper or a simple text editor. Pay attention to semi-colons and pointer syntax.

Review Operating System fundamentals. Even if you work mostly bare-metal, Lyft expects you to understand concepts like context switching, stack overflow, and memory protection units (MPU).

10. Summary & Next Steps

Becoming an Embedded Engineer at Lyft is an opportunity to work on products that physically move the world. The role demands a unique blend of low-level software expertise and high-level system architectural vision. You will be challenged to write efficient, bulletproof code that survives in the wild, powering the fleet of vehicles that defines modern urban transportation.

To prepare, focus heavily on C/C++ fundamentals, RTOS concepts, and System Design. Move beyond simple coding puzzles and practice architecting full embedded solutions—thinking about power, memory, and hardware interfaces. Review your past projects so you can discuss the "why" behind your technical decisions in depth.

The compensation data above provides a baseline for the role. Keep in mind that for specialized engineering roles like Embedded, total compensation often includes significant equity components. Candidates with strong system design skills and relevant industry experience (e.g., automotive, IoT) can often command the upper end of these ranges.

You have the roadmap. Now, dive into the details, brush up on your datasheets, and get ready to show Lyft how you can help build the future of transportation. Good luck!