Software Development Engineer II, Efficiency & Performance, Alloy

Amazon runs one of the world’s most complex eCommerce platforms, where operational efficiency directly drives profitability and customer satisfaction. Efficiency is core to Amazon’s DNA, reflected in the Leadership Principle of Frugality and the Flywheel strategy that lowers cost structures to fuel growth. With the cost of operating Amazon’s global infrastructure measured in billions of dollars, achieving true economies of scale rather than allowing scale to increase costs is essential to our success.

The Alloy team serves as Amazon’s central efficiency organization, leading company-wide cost optimization through intelligent and automated use of AWS resources. Our work spans thousands of internal services, enabling large-scale efficiency improvements with minimal engineering effort from partner teams. We drive optimization across multiple layers of Amazon’s stack, focusing on GPU efficiency infrastructure for AI/ML workloads through centralized scheduling, software performance profiling, and end-to-end storage optimizations through data lifecycle management. These cross-cutting initiatives transform isolated team optimizations into scalable, safe, and reusable systems that continuously improve efficiency across Amazon.

As a Software Development Engineer in Alloy , you will collaborate with service and infrastructure teams across Amazon to identify and eliminate performance bottlenecks in large-scale distributed systems. You will design and build mechanisms to measure, analyze, and automate performance improvements, using data to set and drive company-wide efficiency goals. You will work closely with Principal and Distinguished Engineers, gaining exposure to Amazon’s most advanced systems while developing deep technical expertise and leadership skills. Your work will directly influence how Amazon’s software and services operate at scale, delivering measurable cost savings in the tens to hundreds of millions of dollars each year and advancing Amazon’s commitment to operational excellence and sustainability.

Key job responsibilities

• Design and implement software solutions across the full development lifecycle—from product definition and scoping through coding, testing, deployment, and ongoing maintenance—ensuring high-quality, maintainable, and well-documented code.
• Collaborate with customers, stakeholders, and cross-functional peers to understand business and customer needs, translating requirements into scalable system designs that account for performance, security, and extensibility tradeoffs.
• Identify and resolve operational issues at their root cause, driving improvements to team operations and reducing support costs through proactive problem-solving and process enhancements.
• Evaluate and integrate generative AI tools where appropriate to augment productivity and quality, applying responsible practices to refine outputs and accelerate development workflows.
• Mentor and coach fellow engineers through code reviews and knowledge sharing, actively training new team members on system architecture, construction, and operational best practices.

A day in the life
In this role, you will:

• Solve performance and efficiency problems that manifest at scale.
• Design metrics and measure performance and cost efficiency of services in Amazon's ecosystem.
• Collaborate with service teams to identify inefficiencies, and design and implement solutions.
• Design and develop highly available components and profiling tools.

About the team
Our team is focused on building reliable, scalable software that directly impacts Amazon's customers. We value collaboration, clear communication, and a commitment to continuous improvement. Every engineer has a voice in technical decisions, and we encourage thoughtful debate to arrive at the best solutions. We are investing in new capabilities and looking for engineers who are excited to help shape our technical direction, grow their skills, and contribute to an inclusive environment where everyone can do their best work.