Principal Software Engineer, Backend

CMT is looking for a Principal Backend Software Engineer to produce scalable software solutions to reliably collect and manage data from sensors on smartphones and connected devices in vehicles. In this role, you will design architecture and backend infrastructure, and build features and applications that meet the needs of our customers. If you’re interested in using your skills to make the world's roads and drivers safer, we’d like to meet you. The person in this role will own the architecture and evolution of the backend systems that power DriveWell Fusion. You will design and scale high-throughput data pipelines, REST APIs, and real-time event processing systems that handle millions of device connections daily. You will partner with ML and Data Science teams to build the compute and data infrastructure that supports model training, feature engineering, and large-scale inference — including GPU-accelerated workloads. You will drive infrastructure-as-code practices, CI/CD reliability, and system observability to ensure our platform remains performant and resilient as we grow. As a technical leader, you will mentor engineers, set technical direction, and collaborate with product and engineering stakeholders to deliver solutions that keep tens of millions of drivers safe.

CMT has helped protect over 65 million drivers and prevent over 126,000 crashes worldwide. We build AI to solve some of the most difficult challenges in mobility — understanding and reducing risk, detecting crashes, and getting people life-saving help. The problems are hard. The impact is real. No matter your role, your work will matter at CMT.

Responsibilities:

Participate throughout the planning process, collaborating with product managers, data scientists, and fellow engineers to balance technical feasibility with customer needs

Use independent judgment and discretion to implement and enhance solutions for telematics insights enabled by our processing pipelines

Identify and measure key production performance metrics, ensuring scalability and efficiency

Design, implement, and maintain automated tests for telematics solutions, ensuring safe delivery of features and fixes

Ensure high bar for quality within our sphere of influence

Provide expert guidance on cloud software architecture

Keep the codebase healthy amidst increasing complexity

Mentor junior engineers as needed

Complete any additional tasks as they arise

Qualifications:

Bachelor’s degree or equivalent years of experience and/or certification in Computer Science, Engineering, or related field

7+ years of relevant professional experience

Proven experience with development at scale

Fluency in at least one programming language with ability to learn Python, Go, C++

Experience with continuous deployment, and test-driven development (TDD)

Experience with relational database (RDBMS) schema design

Comfortable with AWS or similar services

EC2, S3, Lambda, SNS, SQS, RDS (Postgres), Dynamo

Terraform, Terragrunt

Knowledgeable of containerization technologies (specifically Docker)

Ability to work independently when needed and to learn quickly

Nice to Haves:

Experience with large-scale cloud compute for ML inference, including GPU-accelerated infrastructure (e.g., EC2 GPU instances, SageMaker, EKS with GPU scheduling), GPU vs CPU workload allocation, model serving at scale, and trade-offs between batch and real-time inference

Experience building and operating data pipelines (ETL/ELT) at scale, and designing the data infrastructure that ML/Data Science teams rely on for feature engineering, model training, and production inference

Hands-on experience designing and operating high-throughput backend systems handling millions of API requests and device connections daily, including real-time data ingestion and event-driven architectures (message queues, streaming platforms)

Hands-on experience with containerization (Docker), container orchestration (AWS ECS or Kubernetes), and infrastructure-as-code using Terraform for managing cloud environments at scale

Proficiency with observability and monitoring (Datadog, CloudWatch) including designing monitors, alerts, and SLOs

Strong knowledge in web security, session management, and experience with network diagnostics and analytics tools

Experience using AI-assisted development tools (e.g., Claude Code, Cursor) as part of daily engineering workflows

Compensation and Benefits:

Fair and competitive salary based on skills and experience, and annual performance bonus

Equity may be awarded in the form of Restricted Stock Units (RSUs)

Medical, Dental, Vision and Life Insurance, matching 401k, short-term long-term disability and parental leave

Unlimited Paid Time Off including vacation, sick days public holidays

Flexible scheduling and work from home policy depending on role and responsibilities

Base Salary Range

The base salary range for this position is: $167,200 to $209,000. This range is specifically for Cambridge, MA

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