---
title: "Start a Builder Session"
canonical: "https://help.cartinuum.com/space/WC/4538204198/Start%20a%20Builder%20Session"
format: markdown
---
Managed Experience Builder uses on-demand builder sessions to provide a dedicated Experience Builder environment for your organisation.

Before you can create or edit applications, you must start a builder session.

### What is a Builder Session?

A builder session is a dedicated Experience Builder environment that contains:

- Your applications
- Installed custom widgets
- Tenant-specific configuration
- Integration with your registered ArcGIS portal

Unlike deployed applications, builder environments are only started when required. This reduces infrastructure costs while ensuring that you always have access to a fully configured Experience Builder environment when needed.

### Before You Begin

Ensure that:

- Your Managed Experience Builder subscription has been linked to an ArcGIS Online or ArcGIS Enterprise portal.
- You have permission to create and edit Experience Builder applications within your ArcGIS environment.

If your portal has not yet been registered, see:

[Register Your ArcGIS Portal](https://bgt-innovation.atlassian.net/wiki/spaces/WC/pages/4538138657)

### Open Managed Experience Builder

Navigate to the **My Extensions** page and locate your **Managed Experience Builder** subscription.

Once your portal has been registered, the **Open** button will become available.

![Screenshot of a Managed Experience Builder subscription showing the Open button](media://e7133a7d-05ec-4ed3-8f79-89b8031f5069)

Select **Open** to access the Managed Experience Builder control page.

### Select a builder version

In the session launch interface, you can view the Experience Builder version assigned to the session. If you do not select a version, the system selects the latest available version automatically. Click `Change` to select a different builder version for the session.

### Start a Session

When no builder session is running, the control page will display a message similar to:

> Session is stopped

Select **Start session**.

![Screenshot of the Managed Experience Builder control page showing the Start session button](media://6de46fb1-ce69-49c4-bea8-5c58542827e6)

Managed Experience Builder will begin preparing your builder environment.

During startup, the platform:

- Creates a dedicated builder environment for your organisation.
- Loads your applications and configuration.
- Makes installed custom widgets available.
- Connects the environment to your registered ArcGIS portal.

### Wait for Startup

Starting a builder session typically takes a few minutes.

You may leave the page open while the environment starts.

### Launch Experience Builder

Once startup is complete, a **Launch** button will become available.

![image-20260619-031410.png](media://49a8b97e-2463-48dc-b373-edc61365972e)

Selecting **Launch** opens the Experience Builder sign-in page.


Continue to:

[Sign In to Experience Builder](https://bgt-innovation.atlassian.net/wiki/spaces/WC/pages/4538269743)