AWS Lambda functions can now mount Amazon S3 buckets as file systems with S3 Files

AWS Lambda now supports Amazon S3 Files, enabling your Lambda functions to mount Amazon S3 buckets as file systems and perform standard file operations without downloading data for processing. Built using Amazon EFS, S3 Files gives you the performance and simplicity of a file system with the scalability, durability, and cost-effectiveness of S3. Multiple Lambda functions can connect to the same S3 Files file system simultaneously, sharing data through a common workspace without building custom synchronization logic.

The S3 Files integration simplifies stateful workloads in Lambda by eliminating the overhead of downloading objects, uploading results, and managing ephemeral storage limits. This is particularly valuable for AI and machine learning workloads where agents need to persist memory and share state across pipeline steps. Lambda durable functions make these multi-step AI workflows possible by orchestrating parallel execution with automatic checkpointing. For example, an orchestrator function can clone a repository to a shared workspace while multiple agent functions analyze the code in parallel. The durable function handles checkpointing of execution state while S3 Files provides seamless data sharing across all steps.

To use S3 Files with Lambda, configure your function to mount an S3 bucket through the Lambda console, AWS CLI, AWS SDKs, AWS CloudFormation, or AWS Serverless Application Model (SAM). To learn more about how to use S3 Files with your Lambda function, visit the Lambda developer guide.

S3 Files is supported for Lambda functions not configured with a capacity provider, in all AWS Regions where both Lambda and S3 Files are available, at no additional charge beyond standard Lambda and S3 pricing.