Changelog

The following patches are now available on the Stable release channel:

• Retool 3.334.11
• Retool 3.300.27

Update your Retool instance to apply the latest bug fixes and security patches.

Retool 3.383 is now available on the Edge release channel for self-hosted organizations.

Admins can now configure memory limits for workflow code execution at the org level, and workflow editors can override those limits on a per-workflow basis.

• Org-level defaults: In Settings, go to the Advanced section and click Advanced settings to set a default memory limit (MB) that applies to all workflow runs in your organization.
• Workflow-level overrides: Open any workflow and go to Settings to override the org default for that workflow.

When a workflow runs a code block, the executor enforces the most specific limit available (workflow > org > server default). If a block exceeds its limit, it fails immediately with a clear error.

Customers who are not configuring limits see no behavior change — the server default of 2,500 MB memory applies. For customers whose workflows were hitting out-of-memory errors, limits can now be tuned without requiring infrastructure changes.

Retool now provides a native integration for ClickHouse, an open-source column-oriented database designed for real-time analytics. You can create a ClickHouse resource and use it to query analytical data with SQL—including ClickHouse-specific functions and aggregations—build dashboards on live data, and insert records from apps and automations.

Retool now provides a native integration for Azure Blob Storage, Microsoft's scalable object storage service. With the Azure Blob Storage resource, you can upload and download files, generate signed URLs for temporary secure access, and copy, delete, and organize objects across containers—all from Retool apps and automations.

Claude Opus 4.7 is now available on Retool Cloud through Anthropic and Amazon Bedrock. It can be used with AI resource queries, with Retool Agents, and in Assist. Support for self-hosted Retool is coming in an upcoming release.

GPT-4 Turbo, GPT-4.1 Nano, and GPT-5.4 are also now available for use with Retool Agents.

You can now select the Python version used by a workflow from the Languages & Libraries tab. Click ... next to Python, select Update version, and choose between Python 3.10 and 3.14.

Python 3.14 does not include built-in libraries. When you upgrade, Retool automatically identifies any built-in libraries your workflow uses and installs them as custom libraries.

Retool now supports an MCP server, which enables you to interact with your Retool organization from your chosen agentic environment.

Retool's MCP server currently supports tools that help you manage your organization and its users. For example, you can use the MCP for the following use cases:

• Write queries against resources to power data analysis.
• Bulk-invite users or manage pending invites.
• Audit the users who have access to your organization.
• Inspect organization and resource environment configurations.
• List all connected resources and see their configuration.

Refer to the tool reference for the full list.

Retool is actively adding additional tools that expand the capabilities of the MCP server to include additional Retool functionality, including app building.

Python 3.10 will reach end of life on October 31, 2026. After this date, Retool will no longer support Python 3.10 in Workflows.

What's changing​

New and existing workflows on Python 3.10 will continue to run but they will not be supported. They will not be automatically migrated to a newer version.

How to upgrade existing workflows​

Python 3.14 is rolling out to cloud instances and will be available in an upcoming self-hosted release.

1. Open the workflow and go to the Languages & Libraries tab.
2. Click ... next to Python and select Update version.
3. Choose Python 3.14 and click Apply.

When you upgrade, Retool automatically identifies built-in libraries your workflow uses and installs them as custom libraries. Python 3.14 is mostly backwards-compatible, but Retool recommends publishing a workflow release before upgrading so you can revert if needed.

See Configure Python version for full details on how to upgrade and revert to a previously published release.

Timeline​

The following patches are now available on the Stable release channel:

• Retool 3.334.8
• Retool 3.300.24
• Retool 3.300.23
• Retool 3.284.29

Update your Retool instance to apply the latest bug fixes and security patches.