---
category: [Administration & Integrations, Administration & Integrations/Custom Integrations & Apps, Platform and Product Extensions, Platform and Product Extensions/Workday Extend, Platform and Product Extensions/Integration]
keyword: Extend
nav: wcp_docs
parent_url: /wcp_docs/
title: Create Extend Apps Using App Builder
layout: subsection
---

### Prerequisites

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-   Access to the Workday Developer Site.
-   Account on a WCP Development tenant.


### Context

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Create a custom app using App Builder on the Workday Developer Site. Code all of your app components on the Developer Site, adding any orchestrations you created in Orchestration Builder. Validate your app's code before you save your app to App Hub and deploy it to a Development tenant. For details on each app component, see the App Components Reference section.

<b>The Reference ID of an App</b>

The reference ID of an app follows this naming convention: `<appId>_<accountSuffix>`, where:

-   `<appId>` - The ID entered when creating the app with the Workday Extend Plugin for IntelliJ. This ID must:

    -   Be unique within the account.
    -   Be meaningful and easily identifiable across Workday Extend tools and logs.
    -   Begin with a letter.
    -   Use `a–z`, `A-Z`, `0–9`, `.`, or `-`.

-   `<accountSuffix>` - A unique ID for your account.


After you create your app and upload it to App Hub, App Hub automatically appends the `<accountSuffix>` to the `<appId>` to create the unique reference ID of your app. Example: `myWcpApp_zsttxv`.

<b>Note:</b> You can't reuse the Reference ID of an app, even if you delete the app from the Workday Developer Site.

### Steps

1.  <a id="step_N10054_N10051_N1001F_N10001"></a>On the Workday Developer Site home page, click <b>Create an Extend App</b>.
2.  Select an option:

<table><thead><tr><th>Option</th><th>Description</th></tr></thead><tbody><tr><td><b>Copy from App Catalog</b></td><td>Make a copy of an existing Extend app and amend it to suit your requirements. <p>Select the app you want to copy. Amend the copy's <b>Name</b> and <b>Reference ID</b> as required and, optionally, provide a <b>Description</b>.</p></td></tr><tr><td><b>Upload a Zip File</b></td><td>Upload an existing Extend app that's been saved locally as a Zip file. <p>Provide a <b>Name</b>, a <b>Reference ID</b> , and, optionally, a <b>Description</b>. Select the Zip file.</p></td></tr><tr><td><b>Start from Scratch</b></td><td>Begin with a blank app. <p>Provide a <b>Name</b>, a <b>Reference ID</b> , and, optionally, a <b>Description</b>.</p></td></tr></tbody></table><br/>

3.  Connect to a Development tenant.

    See: [Connect to a Development Tenant](/wcp_docs/GUID-f9ad6bdf-f687-4263-9cd0-12bd2b0ebf54-enHYPHENus.html).

4.  <a id="step_N10074_N10046_N10028_N10001"></a>Your app opens in App Builder, where you can add components. You can:

    -   Click the <b>Add Component</b> icon above the left navigation pane, select a component <b>Type</b> from the drop-down menu, then enter a <b>Name</b> for the component.
    -   Mouse over a component type, click the plus sign (<b>+</b>) next to the component type, then enter a <b>Name</b> for the component.

    <b>Note:</b> When you add a model component, App Builder notifies you that doing so will queue all promotions to Implementation, Sandbox, or Production tenants until the Friday Maintenance Window. These are the model components:

    -   Attachment
    -   Business Object
    -   Business Process
    -   Report
    -   Security Domain
    -   Task

5.  <a id="step_N100C4_N10046_N10028_N10001"></a>Edit your app components. Click each component in the left navigation pane, then edit the JSON of the component in the content pane.

    <b>Note:</b> You can also edit model components in Visual mode. Use the toggle switch in the upper right of the interface to switch between Code and Visual modes.

6.  <a id="step_N10123_N1008F_N10068_N10001"></a>(Optional) Click <b>Orchestrations</b> in the <b>Logic</b> section of the components panel to view any orchestrations you've created for your app. Click an orchestration's name to open it in Orchestration Builder. Click <b>Add Orchestration</b> to create a new one in Orchestration Builder. See [Steps: Create Extend App Orchestrations](/wcp_docs/hib1626197091901.html).
7.  <a id="step_N100F2_N10046_N10028_N10001"></a>Click <b>Validate</b> to validate your app's code.

    App Builder can validate your app's code at any time before you save your code to App Hub, enabling you to avoid build errors during deployment.

    This validation includes schema, semantic, and syntax validations. App Builder doesn't perform some schema validations in real time.

    You can drag the top of the validation pane up or down to expand or contract the pane.

8.  <a id="step_N10107_N10046_N10028_N10001"></a>Click <b>Save to App Hub</b> or <b>Save and Deploy</b>.

    -   <b>Save to App Hub</b> validates and saves your app's code to App Hub and generates a build log.
    -   <b>Save and Deploy</b> also prompts you to select a Development tenant for deployment.

    <b>Note:</b> App Builder automatically saves any changes that you make to your app's code to your App Builder session. To discard changes made during your session, click the related actions menu to the left of the <b>Validate</b> button, then click <b>Discard Changes</b>. When you do this, App Builder warns you that doing so will irreversibly revert the changes in your session to the version currently saved to App Hub, and enables you to cancel the discard operation.



### Next Steps

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To install your app on an Implementation tenant, promote the app from the <b>Promotions</b> tab on the Console, then install the app on the Implementation tenant.