wandb · ngrayluna · Jul 9, 2026 · Jul 9, 2026 · Jul 9, 2026 · mdlinville
@@ -35,7 +35,7 @@ In an [automatic workspace](/models/app/features/panels#workspace-modes), W&B cr
     1. Click **Create [NUMBER] panels**.
 1. To add a custom line plot instead, click **Line plot**.
     1. Configure the line plot's data, grouping, and display preferences using the corresponding tabs. For details, see [Edit line plot settings](#edit-line-plot-settings).
-    1. To add calculated expressions to the x-axis or y-axis, click **Expressions**. [JavaScript regular expressions](https://www.w3schools.com/js/js_regexp.asp) are supported.
+    1. To add calculated expressions to the x-axis or y-axis, click **Expressions**. Use [Google's RE2 syntax](https://github.com/google/re2/wiki/Syntax) when defining regular expressions.
 1. Select the type of panel to add, such as a chart. The panel's configuration details appear with selected defaults.
 1. Optionally, customize the panel and its display preferences. Configuration options depend on the type of panel you select. For more information about the options for each type of panel, see [Line plots](/models/app/features/panels/line-plot/) or [Bar plots](/models/app/features/panels/bar-plot/).
 1. Click **Apply**.
@@ -46,20 +46,20 @@ In an [automatic workspace](/models/app/features/panels#workspace-modes), W&B cr
 This feature is in preview, available by invitation only. To request enrollment, contact [support](mailto:support@wandb.com) or your AISE.
 </Note>
 
-In an [automatic workspace](/models/app/features/panels#workspace-modes), W&B creates a single-metric line plot automatically for each logged metric. This section shows how to create a single line plot that shows multiple metrics together, defined by a JavaScript regular expression. You can optionally consolidate many single-metric plots into a single multi-metric plot. This can improve the performance of a workspace with many logged metrics, and can help you analyze the results of your runs.
+In an [automatic workspace](/models/app/features/panels#workspace-modes), W&B creates a single-metric line plot automatically for each logged metric. This section shows how to create a single line plot that shows multiple metrics together, defined by a [RE2 syntax](https://github.com/google/re2/wiki/Syntax). You can optionally consolidate many single-metric plots into a single multi-metric plot. This can improve the performance of a workspace with many logged metrics, and can help you analyze the results of your runs.
 
 1. Navigate to your workspace.
 1. To add a line plot globally, click **Add panels** in the control bar near the panel search field.
 
     To add a line plot directly to a section instead, click the section's **action (<Icon icon="ellipsis" iconType="solid"/>)** menu, then click **+ Add panels**.
 1. Click **Quick panel builder**, then click the **Multi-metric panels** tab.
-1. In **Regex** enter an expression in [JavaScript regular expression](https://www.w3schools.com/js/js_regexp.asp) format. As you type, the UI updates to show which metrics match the expression. By default, the plot name shows the regular expression used by the plot. The plot includes lines for all metrics that match the expression, including metrics logged in the future.
+1. In **Regex** enter an expression in [RE2](https://github.com/google/re2/wiki/Syntax) format. As you type, the UI updates to show which metrics match the expression. By default, the plot name shows the regular expression used by the plot. The plot includes lines for all metrics that match the expression, including metrics logged in the future.
 1. To optionally remove duplicate single-metric panels when the multi-metric plot is created, toggle **Clean up auto-generated panels**. A preview shows which panels are cleaned up. <Note>When this option is turned on, W&B doesn't create a single-metric plot for a newly logged metric that matches the expression. Instead, it appears only in this multi-metric plot.</Note>
 1. Click **Create [NUMBER] panels**.
 
 ### Multi-metric regular expressions
 
-Multi-metric line plots use [JavaScript regular expressions](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Guide/Regular_expressions) to match metric names. The following sections describe common use cases and provide more details about how the regular expressions work, such as how capture groups affect the panels that W&B creates.
+Multi-metric line plots use [Google's RE2](https://github.com/google/re2/wiki/Syntax) syntax to match metric names. The following sections describe common use cases and provide more details about how the regular expressions work, such as how capture groups affect the panels that W&B creates.
 
 #### Common use cases
 

@@ -412,7 +412,9 @@ sqrt(${summary:loss}*100)+sqrt(${summary:loss}*100000)
 
 
 ### Multi-metric panel expressions
-Use a regular expression to create a single line plot that shows multiple metrics together (including matching metrics logged in the future). For detailed instructions, see [Add a line plot](/models/app/features/panels/line-plot#multi-metric-line-plot).
+Use a regular expression to create a single line plot that shows multiple metrics together (including matching metrics logged in the future). Use [Google's RE2 syntax](https://github.com/google/re2/wiki/Syntax) when defining a regular expression.
+
+For detailed instructions, see [Add a line plot](/models/app/features/panels/line-plot#multi-metric-line-plot).
 
 For example:
 - Instead of creating separate panels for each layer's metrics, you can view them together in a single panel. For example, if you log metrics with consistent naming, like `layer_0_loss`, `layer_1_loss`, and `layer_2_loss`, you can use a regex like `layer_\d+_loss` to display all layer losses on one plot.

@@ -39,6 +39,10 @@ This section describes the events related to an artifact that can trigger an aut
 - **An artifact alias is added**: Trigger a specific step of your workflow when a new artifact version in a project has an alias applied that matches the **Alias regex** you specify. For example, run a series of downstream processing steps when an artifact has the `test-set-quality-check` alias applied, or run a workflow each time a new artifact version has the `latest` alias. Only one artifact version can have a given alias at a time.
 - **An artifact tag is added**: Trigger a specific step of your workflow when an artifact version in a project has a tag applied that matches the **Tag regex** you specify. For example, specify `^europe.*` to trigger a geo-specific workflow when a tag beginning with the string `europe` is added to an artifact version. Use artifact tags for grouping and filtering. You can assign the same tag to multiple artifact versions.
 
+<Note title="Regular expression syntax">
+For `Alias regex` and `Tag regex` fields, use Google's [RE2 syntax](https://github.com/google/re2/wiki/Syntax).
+</Note>
+
 ### Run events
 
 The following sections describe how to configure an automation that starts based on a change in a [run's status](/models/runs/run-states) or a change in a [run's metric value](/models/track/log#what-data-is-logged-with-specific-wb-api-calls).

@@ -71,7 +71,7 @@ A W&B admin can create automations in a project.
         1. For automations triggered by a run, optionally specify one or more run filters:
 
             - **Filter to one user's runs**: Include only runs created by the specified user. Click the toggle to turn on the filter, then specify a username.
-            - **Filter on run name**: Include only runs whose names match the given regular expression. Click the toggle to turn on the filter, then specify a regular expression.
+            - **Filter on run name**: Include only runs whose names match the given regular expression. Click the toggle to turn on the filter, then specify a regular expression. Use [Google's RE2 syntax](https://github.com/google/re2/wiki/Syntax) when defining regular expressions.
     1. Click **Next step**.
 1. Select the team that owns the [Slack integration](#add-a-slack-integration).
 1. Set **Action type** to **Slack notification**. Select the Slack channel, then click **Next step**.

@@ -79,7 +79,7 @@ A W&B admin can create automations in a project.
         1. For automations triggered by a run, optionally specify one or more run filters.
 
             - **Filter to one user's runs**: Include only runs created by the specified user. Click the toggle to turn on the filter, then specify a username.
-            - **Filter on run name**: Include only runs whose names match the given regular expression. Click the toggle to turn on the filter, then specify a regular expression.
+            - **Filter on run name**: Include only runs whose names match the given regular expression. Click the toggle to turn on the filter, then specify a regular expression. Use [Google's RE2 syntax](https://github.com/google/re2/wiki/Syntax) when defining regular expressions.
 
           The automation applies to all collections in the project, including those added in the future.
     1. Click **Next step**.

@@ -95,6 +95,10 @@ W&B supports the following comparison and logical operators for filtering regist
 | `$exists` | Field exists/doesn't exist |
 | `$contains` | String contains value |
 
+<Note title="Regular expression syntax">
+For `regex` queries, use [Google's RE2 syntax](https://github.com/google/re2/wiki/Syntax) when defining regular expressions.
+</Note>
+
 ### Example queries
 
 The following code examples demonstrate some common search scenarios. 

@@ -50,7 +50,7 @@ The following features are available in the mobile app.
     - **Mobile-optimized panel grouping**: Panels are automatically grouped by name into collapsible sections. You can collapse the ungrouped metrics section to focus on named sections. Sections are a single level (not nested), and grouping follows the same rules as [workspace panels](/models/app/features/panels) in the W&B web app, so the layout stays consistent when you move between desktop and your phone.
     - **Star panels**: See your most important panels at a glance. When viewing a run or a project, click the star icon at the top of a panel to star it. To filter the list to only starred panels, click the **Starred** tab at the top of the list.
     - **Star metrics**: When viewing an important metric in detail view, click the star icon to star it.
-    - **Search panels**: When viewing a run or a project, use the **panel search** field at the bottom of the screen to filter which runs appear in each chart. You can search with [JavaScript regular expressions](https://www.w3schools.com/js/js_regexp.asp) to match patterns in run names.
+    - **Search panels**: When viewing a run or a project, use the **panel search** field at the bottom of the screen to filter which runs appear in each chart. You can search with [RE2 syntax](https://github.com/google/re2/wiki/Syntax) to match patterns in run names.
     - **Chart tooltips**: On line charts, tooltips show metric values with up to four decimal places so you can read small changes accurately.
     - **Stop runs**: When viewing an in-progress run, click the **action (<Icon icon="ellipsis" iconType="solid"/>)** menu, then click **Stop run**.
     - **View console logs**: View [console logs](/models/runs/view-logged-runs#logs) for active or completed runs, or download logs for completed runs. The app polls active runs for new log lines every 5 seconds. The most recent 10,000 lines display by default, and you can scroll backward to view older logs. Log search stays responsive even for large outputs.