AWS Networking builds the infrastructure that powers every customer workload in the cloud. ENA Express is a next-generation EC2 networking feature that leverages the Scalable Reliable Datagram (SRD) protocol - developed by AWS - to deliver industry-leading networking performance: dramatically lower tail latency, higher bandwidth utilization, and consistent packet delivery at scale.
We are looking for a Senior Software Development Engineer to join the ENA Express team. You will design, build, and own features across the full ENA Express software stack: Firmware on the Nitro-Card, user-space libraries, control plane components, and the performance analytics systems that help our customers get the most out of their network
This is high-ownership work - your code runs on a fleet of millions of EC2 instances, supporting customers who demand the absolute best from their network, including HPC clusters, large-scale ML training, financial services, and other latency-critical applications.
Key job responsibilities
Design and develop features across the AWS Networking software stack on Nitro Cards.
Deep-dive into ENA Express and the underlying SRD protocol and L3/L4 networking to optimize packet delivery, reduce tail latency, and improve bandwidth utilization.
Collaborate with hardware and firmware partners to define software/hardware interfaces and surface programmable capabilities to the software layer
Partner with EC2 platform and service teams to integrate ENA Express features into the broader AWS networking ecosystem
Mentor junior and mid-level engineers, lead design reviews, and champion engineering best practices across the team
Drive operational excellence: build observability, contribute to on-call health, and lead incident response and post-mortems
About the team
We are a team of senior engineers with deep expertise in systems software, networking protocols, and EC2 infrastructure. Our work spans the full stack - from the Firmware on the driver Card, and NIC driver layer up through the EC2 control plane - and we collaborate closely with hardware, firmware, and platform partners. We care deeply about technical craft, operational quality, and each other's growth.