Building the Future of Cloud and PC: How Arm and Microsoft are Supercharging Developer Innovation 

Together, Arm and Microsoft are co-engineering a future where innovation isn’t limited by the power constraints of devices, or different deployment environments.  

At Microsoft Build, we’re showcasing significant momentum for our vision of ensuring that the entire Microsoft software ecosystem can access and benefit from the Arm compute platform. Developers can accelerate applications and workloads everywhere, whether it’s in the cloud on Azure or at the edge on Windows on Arm PCs.  

Highlights include: 

• Leading 1st and 3rd party application workloads being deployed on Arm-based Azure Cobalt-100, including Microsoft Defender Endpoint and Teams, Adobe, Databricks and Snowflake; 

• New Arm Cloud Developer Access Program for Azure to accelerate migration to Cobalt; 

• Recent KleidiAI integration with ONNX Runtime leading to 40% increase in tokens per second when running Phi-4 model on Cobalt-100 VMs for faster response times and improved developer experience; and 

• Windows on Arm momentum continues with more Arm-native support for leading applications and enhanced developer support. 

Arm and Microsoft are redefining efficiency and performance

Developers attending Build will get a closer look at Microsoft’s Azure Cobalt 100 processor, which is optimized for performance, efficiency, and scalability. Powered by Arm Neoverse Compute Subsystems (CSS), the Azure Cobalt 100 processor is engineered to deliver increasing efficiency and performance for general purpose workloads in Microsoft Azure. This isn’t just about raw compute power—it’s about sustainable innovation. Microsoft’s choice to build on Arm was pivotal in advancing its sustainability goals, with an emphasis on unlocking significant power savings across its datacenters. 

For developers, this translates into greater power efficiency, lower operational costs, and the ability to scale AI and cloud-native applications more effectively than ever before. 

Build is illustrating the great momentum behind Cobalt, with the expansion of 1st and 3rd party application workloads running on Arm-based Azure Cobalt-100 chips. Microsoft is deploying two of its core services – Defender for Endpoint and Teams – on Azure Cobalt 100-powered instances. Meanwhile, leading 3rd party applications, like Adobe, Databricks, and Snowflake, are being deployed on Azure Cobalt-100. 

Introducing Arm Cloud migration for Microsoft Cobalt 100 

To support and accelerate developer adoption of the Arm architecture in the cloud, we recently launched a comprehensive cloud migration initiative. Central to this initiative is our new  Cloud Migration Resource Hub, offering more than 100+ detailed Learning Paths designed to guide developers through migrating common workloads seamlessly across multiple platforms. 

Using these tools and community support, developers can streamline the migration of existing applications or natively build modern cloud services optimized for performance and efficiency. From .NET and Java apps to open source databases and web services, Cobalt 100 VMs deliver scalable, cost-effective compute for cloud-native and AI workloads. 

Accelerated AI on Cobalt-100 VMs with KleidiAI Integration in ONNX Runtime

A recent milestone is the successful integration of Arm KleidiAI into Microsoft’s ONNX Runtime. This supercharges AI experiences for applications running on Windows on Arm devices by enabling smarter, faster AI interactions directly on the device with no additional developer effort needed.  

To showcase the performance uplift, consider the Phi-4 Mini model running on Cobalt-100 VMs with ONNX Runtime. When KleidiAI is enabled, developers can see significant gains: 

• Token throughput (tokens/second) increased by up to 40%; 
• Time-to-first-token (TTFT) improved by over 34%; and 
• Even on smaller 8-core instances, KleidiAI boosted throughput from by approximately 37 percent and reduced time-to-first-token (TTFT) by around 16%. 

Windows on Arm provides a full-stack developer opportunity 

The evolution of Windows on Arm marks another major milestone. With Arm-native support for leading applications like Microsoft 365, Adobe Creative Cloud, Amazon Prime Video, Zoom, and Fantastical, developers now have a mature, power-efficient platform to target. From Zoom’s seamless video conferencing on Windows on Arm, the dynamic calendar experience in Fantastical, secure browsing through NordVPN, to smarter developer workflows with Pieces for Developers, real-world applications are showing what’s possible on Arm today. 

And thanks to Arm’s collaboration with GitHub and the launch of Windows Runners for GitHub Actions, developers now have a fully optimized CI/CD pipeline for Windows on Arm. With GitHub Actions and CoPilot enhanced by Arm extensions that are free to developers everywhere, teams can speed up testing, integration, and deployment, while taking on multiple workflows at once and adding more performance and efficiency to their AI workloads.  

The future is collaborative—and it’s built on Arm

At Build the message is clear: From on-device AI to hyperscale cloud applications, developers have a unified, power-efficient foundation to build on—powered by Arm and Microsoft. Looking ahead, the Arm and Microsoft partnership will continue to redefine what’s possible when hardware and software innovation meet, enabling transformative experiences from cloud to PC. 

Arm at Build 2025 

You can see Arm at Build through visiting the following sessions:  

• Unleashing price-performance: Cobalt 100 and the future of cloud-native on Arm 

• Run PyTorch natively on Windows on Arm using GitHub Runners

• Tips and tricks to enhance Windows Arm64 App performance 

If you can’t make the event, Arm provides free access to resources on the Arm Learning Path site and Microsoft page on the Arm Developer Hub, helping Windows developers scale their ideas securely, efficiently and sustainably.