--- title: "Prerequisites" url: https://docs.catalyst.zoho.com/en/tutorials/microservice/java/prerequisites/ description: "Build a simple microservice using Catalyst Basic I/O Functions and integrate it with Zoho CRM to send automated counter-based email alerts when more than a specific number of leads are created." last_updated: 2025-10-29T07:02:36Z service: All Services type: tutorial related_links: - name: "CLI Command Reference" url: /en/cli/v1/cli-command-reference/ - name: "Install Catalyst CLI" url: /en/getting-started/installing-catalyst-cli/ - name: "Login CLI" url: /en/cli/v1/login/login-from-cli/ --- # Prerequisites Before you begin building the application, you must have the following prerequisites installed on your system: 1. **Catalyst CLI** \ \ Catalyst CLI contains a host of tools that enable you to initialize, develop, test, and deploy the components of your application from your local machine. We will be working with Catalyst CLI in this tutorial. \ \ You must perform the following actions: 1. **Install Catalyst CLI:** Catalyst CLI is installed through NPM. You must therefore have NPM and Node.js installed on your system before you install the CLI. Refer to the [**Install Catalyst CLI help page**](https://docs.catalyst.zoho.com/en/getting-started/installing-catalyst-cli/) for details on the pre-requisites and the steps to install it. 2. **Log in to Catalyst CLI:** After you install Catalyst CLI, you must authenticate the CLI with your Catalyst account before using it. Refer to the [**CLI Login help page**](https://docs.catalyst.zoho.com/en/cli/v1/login/login-from-cli/) for the steps to login from Catalyst CLI and the various options available for it. 2. **Any IDE tool for Java function code development** \ \ You can use any IDE to work with the Basic I/O function. Some popular choices include Visual Studio Code, IntelliJ IDEA, Eclipse, and Sublime Text. Download and install an IDE of your choice on your system. > If you are a Visual Studio Code IDE user, you can install the **Catalyst Tools** extension, and use your IDE itself in place of the CLI. You can find more details about the Catalyst VS Code extension from this [help section](https://docs.catalyst.zoho.com/en/catalyst-extensions/vs-code-extension/introduction/). 3. **Zoho CRM Professional or Enterprise edition** \ \ To integrate the function with Zoho CRM, we will use [Webhooks](https://help.zoho.com/portal/en/kb/crm/automate-business-processes/actions/articles/webhooks-workflow) and associate it with a [workflow rule](https://help.zoho.com/portal/en/kb/crm/automate-business-processes/workflow-management). Webhooks are not available in the Free edition of Zoho CRM. You can check out the comparisons of various Zoho CRM editions and buy an edition from [this page](https://www.zoho.com/crm/comparison.html).