Announcing the LocalStack for AWS 4.9 Release

Introduction

We’re excited to share the release of LocalStack for AWS 4.9. In addition to some new capabilities, this release focuses on reinforcing the underlying foundations of the project while enhancing both performance and security. These improvements improve alignment with AWS support while ensuring our software has the safety and reliability our users expect.

This release includes updates to several resources that underpin LocalStack for AWS services, including DynamoDB Local, Hadoop, Apache Spark, Glue, k3d, Postgres, Apache ActiveMQ, Python, and Debian Trixie. We’ve also added support for new versions of OpenSearch, new merge strategies for Cloud Pods, CRUD support for EKS access entries, and multi-protocol support for CloudWatch’s additional protocols. Read on for details.

Get your free LocalStack account to access the latest features and enhancements in LocalStack for AWS 4.9!

How to upgrade?

To upgrade to LocalStack for AWS 4.9 using the LocalStack CLI, run:

localstack update all

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

docker pull localstack/localstack:4.9.0 # Community Edition

docker pull localstack/localstack-pro:4.9.0 # Pro Edition

Pin version 4.9.0 in your Docker configuration to ensure reproducibility.

What’s New in LocalStack for AWS 4.9?

• Introduction
• How to upgrade?
• What’s New in LocalStack for AWS 4.9?
• Upgrade Services for Enhanced Performance, Security and Parity
• New Environment Variable for Cloud Pod Merge Strategies
• Add Support for New Versions of OpenSearch
• Support for EKS Access Entries and Access Policies
• Add CloudWatch Support for Multi-protocols
• Miscellaneous
• Deprecations
• Conclusion

Upgrade Services for Enhanced Performance, Security and Parity

As part of our commitment to continuously improving the performance of LocalStack’s emulators and in maintaining the security and reliability of the underlying software, we’ve upgraded the versions of a number of dependencies within LocalStack for AWS including:

• Upgrade DynamoDB local to version 3.1, which includes a number of performance and security improvements including improved performance for PartiQL queries.
• Bump the versions for big data components including Hadoop, Spark, Glue for enhanced security.
• Upgrade the base image to Debian Trixie and the Python version to 3.13 to improve performance and security, including around Python dependencies.
  • Note that due to the upgrade, older volumes with installed extensions (using localstack extension init) will not be detected. Impacted users will need to reinitialize and reinstall the extensions.
  • In addition, MariaDB has been upgraded as part of the migration to Debian Trixie, which will lead to the collation-name differing between AWS and LocalStack
• Drop support for installing PostgreSQL 11, switching to PostgreSQL 12 everywhere where PostgreSQL 11 has been used: RDS, Redshift, Timestream.
• Bump the version of k3d, which is used for local development on Kubernetes, to the latest available for enhanced security.
• Bump the ActiveMQ version to 5.18.7 to improve security and align with supported versions within Amazon MQ.

New Environment Variable for Cloud Pod Merge Strategies

Cloud Pods are a powerful tool that can save the state of your LocalStack instance and easily be stored, versioned, shared, and restored. Cloud Pods support defining a merging strategy when merging a Cloud Pod into an existing LocalStack container with resources. A merge strategy determines how resources are merged when overlapping resources are encountered.

Previously, LocalStack supported defining a merge strategy when loading a Cloud Pod via the CLI via the --strategy option or when using the LocalStack web app. When no strategy was specified, the default strategy (account-region-merge) would be used.

LocalStack for AWS 4.9 introduces a new MERGE_STRATEGY environment variable that can be used to select a default strategy. This is especially useful when auto-loading a Cloud Pod as soon as the LocalStack container is started, as previously only the default strategy could be used.

See the Cloud Pods documentation for more details.

Add Support for New Versions of OpenSearch

OpenSearch Service is an open-source search and analytics engine closely coupled with the Elasticsearch Service. LocalStack for AWS 4.9 adds support for new versions of OpenSearch and updates the default version to align with AWS support.

The new supported versions for OpenSearch are:

• 2.15
• 2.17
• 2.19
• 3.1

The new default version for OpenSearch domains (if no version is set) is now 3.1. Check the OpenSearch documentation for more details.

Support for EKS Access Entries and Access Policies

EKS access entries are the recommended way to grant users access to the Kubernetes API. Within AWS, access entries associate Kubernetes permissions with an IAM identity, allowing a user to control access to an EKS Cluster.

LocalStack for AWS 4.9 adds CRUD support of EKS access entries and access policies. The new supported APIs include:

• AssociateAccessPolicy
• CreateAccessEntry
• DeleteAccessEntry
• DescribeAccessEntry
• DisassociateAccessPolicy
• ListAccessEntries
• ListAccessPolicies
• ListAssociatedAccessPolicies
• UpdateAccessEntry

This support enhances support for IaC stacks deploying EKS and improves general API parity of the LocalStack for AWS EKS service.

Add CloudWatch Support for Multi-protocols

Amazon CloudWatch recently added support for two additional protocols – AWS JSON 1.0 and Smithy RPC v2 CBOR – in public preview. These new protocols provide better overall performance than the AWS Query protocol that was previously the only supported protocol.

LocalStack for AWS 4.9 ensures that our emulator is ready with multi-protocol support for the CloudWatch service in order to align with these upcoming changes to the CloudWatch service.

Miscellaneous

• Implement ListTags, TagResource and UntagResource API support for Backup Vaults and Backup Plans, which are the only resources we support that would support tagging.
• Remove unused Terraform package installer at localstack-core/localstack/packages/terraform.py. If you were using this package installer, please instead refer to our terraform-init extension.

Deprecations

• PostgreSQL 11 Support Removed: LocalStack for AWS 4.9 drops support for installing PostgreSQL 11. All services that previously used PostgreSQL 11 — including RDS, Redshift, and Timestream — now default to PostgreSQL 12. If you rely on PostgreSQL 11 in previous versions, ensure compatibility before upgrading.

• Debian Trixie / Python 3.13 Upgrade: Starting with LocalStack for AWS 4.9, the base image has been upgraded from Debian Bookworm / Python 3.11 to Debian Trixie / Python 3.13. This may impact custom extensions, init scripts, or packages that rely on specific OS packages or Python 3.11.

• Reinitialization Required for Existing Extensions: Due to the base image and Python upgrade, older volumes with installed extensions (using localstack extension init) may not be detected. Users will need to reinitialize and reinstall these extensions after upgrading.

Conclusion

LocalStack for AWS 4.9 solidifies a number of key elements within the software that improve performance, security, stability and API parity for our users while serving as a solid foundation for additional future enhancements.

Upgrade to LocalStack for AWS 4.9 today to accelerate your AWS cloud application development with greater confidence and efficiency.