Announcing the LocalStack for AWS 4.11 Release

Introduction

We’re excited to share the release of LocalStack for AWS 4.11. This release improves AWS parity across a variety of services including new runtime support in Lambdas, expanded API support in Amazon Managed Streaming for Apache Kafka (MSK), S3 Tables and CodePipeline and additional capabilities in our AWS Key Management Service emulation. In addition, LocalStack for AWS 4.11 adds improved support for testing machine learning workflows using RDS and support for persisting EKS cluster contents. Read on for more details!

Get your free LocalStack account to access the latest features and enhancements in LocalStack for AWS 4.11!

Note: If you use LocalStack in host mode via the CLI, please be sure to refer to our deprecations.

How to upgrade?

To upgrade to LocalStack for AWS 4.11 using the LocalStack CLI, run:

localstack update all

If using Docker CLI or Docker Compose, update the Docker image:

docker pull localstack/localstack:4.11.0 # Community Edition

docker pull localstack/localstack-pro:4.11.0 # Pro Edition

Pin version 4.11.0 in your Docker configuration to ensure reproducibility.

What’s new in LocalStack for AWS 4.11?

New Lambda Runtime Support
Improved KMS Support
Expanded API Support for MSK, S3 Tables and CodePipeline
RDS Support for pgvector
Enhanced EKS Peristence
Miscellaneous
Deprecations
Conclusion

New Lambda Runtime Support

At LocalStack, we strive to ensure that you have access to the latest capabilities in AWS as soon as possible. This includes making sure that you have access to the latest runtime updates in Lambda that enable you to use the most up-to-date versions of your favored runtime language. In most cases (as in this one), these runtime updates are available within days of AWS releasing them.

LocalStack for AWS 4.11 includes several Lambda runtime updates including:

Python 3.14
Java 25
Node.js 24

You can learn more about deploying Lambdas to LocalStack in our documentation and more about Lambda supported runtimes in the AWS documentation.

Improved KMS Support

AWS Key Management Service (KMS allows you to easily create, control, and manage the cryptographic keys used to encrypt and protect your data across your applications and AWS resources. LocalStack for AWS 4.11 adds to our already extensive KMS coverage by adding support for a recipient in KMS decrypt and on-demand key rotation for external keys.

KMS Decrypt Recipient

LocalStack for AWS 4.11 now supports the KMS Decrypt Recipient field is used by AWS Nitro Enclaves to decrypt sensitive keys without the host being able to read them. You can read more about this flow in the KMS Decrypt documentation.

KMS On-demand Key Rotation

KMS: On Demand Key Rotation for Imported Key Material Earlier this year, AWS made it possible to import custom key material into external keys thereby allowing use of KeyRotationOnDemand with external KMS keys. This capability is now also supported in LocalStack for AWS as of 4.11.

Expanded API Support for MSK, S3 Tables and CodePipeline

At LocalStack, we are always striving to expand our AWS API coverage to ensure our customers can accurately test their complete end-to-end workflow. LocalStack for AWS 4.11 continues this effort with expanded API support for a number of services.

MSK

Tagging resources in Amazon Managed Streaming for Apache Kafka (MSK) is a powerful and simple way to manage, organize, and control access to your resources. LocalStack for AWS 4.11 inclues support for tagging MSK Resources.

API operations that were added include:

For details on using MSK within LocalStack as well as full API coverage details, visit our MSK documentation.

S3 Tables

Amazon S3 Tables provide support APIs that allow users to configure, monitor, and control the management and performance of individual tables. As of LocalStack for AWS 4.11, we support the following S3 Tables support APIs:

Note that the APIs accept, validate, store, and return maintenance configurations, but the actual maintenance operations (file removal, compaction, snapshot management) are not actively executed.

For more details on using S3 Tables in LocalStack, check our S3 Tables documentation.

CodePipeline

Our team at LocalStack regularly monitors API usage to help identify gaps in API coverage for actively requested APIs. One such missing operation recently identified by our team was the GetPipelineState operation in CodePipeline used to retrieve the state of a pipeline, including the stages and actions. LocalStack for AWS 4.11 resolves this API coverage gap.

For information about how to use CodePipeline within LocalStack, including full API coverage details, visit our CodePipeline documentation.

RDS Support for pgvector

LocalStack continues to improve upon its capabilities in building and testing artificial intelligence (AI) and machine learning (ML) applications. AWS previously announced support for the pgvector extension for Amazon Relational Database Service (RDS) for PostgreSQL. This extension is used to store embeddings from ML models in order to more efficiently perform similarity searches. With LocalStack for AWS 4.11, the pgvector extension is now installed by default when installing a version of Postgres allowing improved emulation of ML workloads.

Enhanced EKS Persistence

Persistence on LocalStack allows you to save and even share the state of your LocalStack instance. This can enable quick and easy setup of complex environments across sessions, between team members or in CI/CD. However, until LocalStack for AWS 4.11, EKS (Elastic Kubernetes Service) persistence was limited as it did not persist the contents of the cluster.

LocalStack for AWS 4.11 has added the ability to persist the state and contents of your emulated EKS clusters between restarts, enabling faster iteration and more realistic local testing of Kubernetes workloads.

By default, cluster contents are not persisted. You can enable saving/loading your Kubernetes resources by starting LocalStack with EKS_PERSIST_CLUSTER_CONTENTS=1. The persistence capability uses Velero under the hood, and we’ve also exposed EKS_VELERO_IMAGE and EKS_VELERO_PLUGIN_AWS_IMAGE to allow further customization of the Velero image and the AWS plugin image.

Miscellaneous

Fixed an issue where the public IP address of EC2 instances started in K8S environment would not resolve to the instances pod.
Fixed the Kafka cluster version in the MSK ListClusters and DescribeCluster APIs.
Fixed an issue where the pod would not be removed when deleting the cluster or stopping LocalStack when running Redis/Valkey container in K8s environment.
Fixed an issue reported that caused a GraphQL schema error in AppSync when defining AWSDateTime or AWSTimestamp scalars.

Deprecations

Starting LocalStack in host mode via the CLI using localstack start --host has been deprecated and is expected to be removed in January 2026. Users of this features are advised to use the default Docker mode instead.

Conclusion

LocalStack for AWS 4.11 continues our ongoing commitment to expanding AWS parity and staying up-to-date with changes across all our supported services. It brings key enhancements to a variety of services including Lambda, Amazon Managed Streaming for Apache Kafka (MSK), S3 Tables, CodePipeline, AWS Key Management Service (KMS) and RDS. Upgrade to LocalStack for AWS 4.11 today to take advantage of all the new capabilities.