Principal Software Engineer, AWS Lambda

Amazon is hiring a Principal Software Engineer, AWS Lambda in Dublin, Ireland. Level rates it ; you can apply on Amazon.

Level's read on this job

On Level's scale, this software engineer role is Little AI ●○○○: aI is not part of the work.
Tools and skills the posting cites include Rust, C and Linux.
Level classifies it as a lead role.
Level lists 20,000+ other open roles at Amazon.

AI in this role

Principal Software Engineer defining the technical vision and architecture for the AWS Lambda execution environment.

RustCLinuxAWS LambdaFirecracker

systems-programmingvirtualizationcloud-infrastructuredistributed-systems

Are you passionate about building the foundational systems that power serverless computing for millions of customers worldwide? AWS Lambda is looking for a Principal Engineer to join our Lambda Experience team in Dublin, Ireland, where you will define the technical vision and drive the architecture for the Lambda execution environment, the system that execute customer code across the globe.

AWS Lambda is one of the fastest-growing services in AWS and sits at the heart of serverless computing. The Lambda execution environment is responsible for securely launching and managing the compute environment where customer code runs. This includes the orchestration of microVM-based isolation using Firecracker, the management of execution environments, and the runtime interfaces that bridge customer code with the Lambda platform. The systems you will work on process millions of invocations per second, operate across multiple AWS Regions, and must deliver consistently low latency while maintaining the highest standards of security and isolation.

As a Principal Engineer on this team, you will own the long-term technical strategy for the Lambda execution environment, working at the intersection of systems programming, virtualization, and cloud infrastructure. You will design and build the next generation of execution environment management, tackle challenges in cold start optimization, resource scheduling, and multi-tenant isolation, and drive the evolution of our Rust and Linux kernel-level components so that, among other things, they are ready to carry our customers’ next generation workloads, including agentic ones. You will operate as both a hands-on builder and a strategic technical leader — writing production code in Rust and C while simultaneously shaping the architectural direction of the Lambda Dublin organization across multiple levels.

You will also play a critical role in growing the engineering team. With strong senior engineers who are deep technically but still developing their strategic thinking and organizational influence, you will mentor and coach the next generation of senior technical leaders. You will establish engineering standards, lead design reviews, and create the technical culture that enables the team to operate at the highest level.

Key job responsibilities
- Define and drive the long-term technical strategy for the Lambda execution environment, ensuring alignment with the broader Lambda and AWS Compute vision.

- Architect and build systems for execution environment management, cold start optimization, and resource scheduling at massive scale.

- Write production code in Rust and C, contributing directly to the most complex and critical components of the execution environment.

- Lead the design and evolution of microVM orchestration, working closely with the Firecracker virtualization stack and Linux kernel interfaces.

- Drive cross-team technical alignment with other Lambda teams, and adjacent AWS Serverless, Container and Compute teams.

- Mentor and develop senior engineers, helping them grow in strategic thinking, influence, and organization-level impact.

- Establish and raise the engineering bar through design reviews, technical standards, and operational excellence practices.

- Represent the Lambda Experience team in senior technical forums across AWS, influencing the direction of serverless compute infrastructure.

A day in the life
You may start your morning reviewing operational metrics for the Lambda Execution Environment, looking at invocation latency percentiles, cold start performance, and resource utilization trends across AWS Regions. You may join a design review where a senior engineer is proposing a new approach to execution environment caching — you will ask probing questions, help them think through edge cases, and guide them toward a solution that balances performance with security isolation.

Mid-morning, you may dive into code, perhaps working on a Rust component that optimizes how execution environments are pre-warmed, or investigating a subtle performance regression in the microVM boot path. After lunch, you may collaborate with the Data Plane team in Seattle that routes Lambda invocations to execution environments, aligning on an upcoming change that affects invocation routing and ensuring the execution environment architecture can accommodate new traffic patterns gracefully.

You may then meet with Lambda Product Managers to discuss the customer experience, providing technical perspective on upcoming features and ensuring that the execution environment roadmap reflects customer needs and feedback. Later in the afternoon, you may spend time with your manager discussing the three-year technical roadmap and how the team's investments in next-generation scheduling will support Lambda's growth trajectory.

You may end the day mentoring one of your senior engineers, helping them prepare a technical proposal that will require them to influence a partner team — coaching them on how to frame the problem, anticipate objections, and build consensus. Throughout the day, you will balance deep technical work with broad organizational influence, serving as the technical anchor for a team that is building one of the most critical execution paths in all of AWS.

Basic qualifications

- Bachelor's degree in Computer Science, Engineering, a related field, or equivalent experience
- Experience with virtualization (Hypervisors, VMware, Xen), or experience in software development
- Experience providing technical leadership on high-impact cross-fucntional technical project
- 12+ years of professional software development experience, with significant depth in systems programming.
- Deep knowledge of Linux kernel internals, including process scheduling, memory management, and namespaces/cgroups.

Preferred qualifications

- Experience with designing and building applications using container and serverless technologies
- Experience in written and verbal communication with the ability to present complex technical information in a clear and concise manner to executives and non-technical leaders
- Experience as a mentor, tech lead or leading an engineering team
- Experience with systems-level programming languages such as Rust and/or C/C++.
- Experience optimizing cold start latency, resource scheduling, or execution environment lifecycle management in multi-tenant systems.
- Experience designing and building large-scale, low-latency, highly available distributed systems.

Amazon is an equal opportunities employer. We believe passionately that employing a diverse workforce is central to our success. We make recruiting decisions based on your experience and skills. We value your passion to discover, invent, simplify and build. Protecting your privacy and the security of your data is a longstanding top priority for Amazon. Please consult our Privacy Notice (https://www.amazon.jobs/en/privacy_page) to know more about how we collect, use and transfer the personal data of our candidates.

Amazon is an equal opportunity employer and does not discriminate on the basis of protected veteran status, disability, or other legally protected status.

Our inclusive culture empowers Amazonians to deliver the best results for our customers. If you have a disability and need a workplace accommodation or adjustment during the application and hiring process, including support for the interview or onboarding process, please visit https://amazon.jobs/content/en/how-we-hire/accommodations for more information. If the country/region you’re applying in isn’t listed, please contact your Recruiting Partner.

How we rate this

Principal Software Engineer, AWS Lambda at Amazon rates 10 out of 100 for how much of the daily work is AI. That makes it Little AI (AI Level 1 of 4). The level is about AI in the job, not seniority.

Classification

Little AI. AI is not part of the work.

●●●● Builds AI80 to 100
●●●○ Works on AI60 to 79
●●○○ Uses AI40 to 59
●○○○ Little AI0 to 39

Levels come from how often the tools, models and workflows of the role are named in the posting itself. Read the description and count the AI tools, models and workflows it names.

Key facts

Principal Software Engineer, AWS Lambda is an open job at Amazon.
Level rates this role AI Level 1 of 4: Little AI.
The role is based in IE, D, Dublin.
The job was posted on May 29, 2026.
Seniority: lead.
Applications are handled by Amazon. Apply on Amazon

Prepare for this job

Built from this posting and from similar jobs on Level.

Skills and AI tools this role asks for

Systems ProgrammingVirtualizationCloud InfrastructureDistributed SystemsRustCLinuxAWS Lambda

Also common in software engineer jobs at this level

Python Java Kubernetes TypeScript React Docker

Pay

Typical software engineer job: $167k

This posting doesn't list pay. Use the typical software engineer figure when pay comes up. See software engineer jobs

Questions you could be asked

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Tell me about a project where virtualization was part of your work. What did you do?
Tell me about a project where cloud infrastructure was part of your work. What did you do?
Tell me about a project where distributed systems was part of your work. What did you do?
Walk me through how you've used Rust in your day-to-day work.

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