task buildWar(type: CubaWarBuilding) {
    singleWar = false
    // ...
    coreWebXmlPath = 'modules/core/web/WEB-INF/production-web.xml'
    webWebXmlPath = 'modules/web/web/WEB-INF/production-web.xml'
}

task buildWar(type: CubaWarBuilding) {
    // ...
    logbackConfigurationFile = 'etc/war-logback.xml'
}

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
         version="3.0">

    <!--Application components-->
    <context-param>
        <param-name>appComponents</param-name>
        <param-value>com.haulmont.cuba</param-value>
    </context-param>

    <!-- Web Client parameters -->

    <context-param>
        <description>List of app properties files for Web Client</description>
        <param-name>appPropertiesConfigWeb</param-name>
        <param-value>
            classpath:com/company/sample/web-app.properties
            /WEB-INF/local.app.properties
            file:${app.home}/local.app.properties
        </param-value>
    </context-param>

    <context-param>
        <description>Web resources version for correct caching in browser</description>
        <param-name>webResourcesTs</param-name>
        <param-value>${webResourcesTs}</param-value>
    </context-param>

    <!-- Middleware parameters -->

    <context-param>
        <description>List of app properties files for Middleware</description>
        <param-name>appPropertiesConfigCore</param-name>
        <param-value>
            classpath:com/company/sample/app.properties
            /WEB-INF/local.app.properties
            file:${app.home}/local.app.properties
        </param-value>
    </context-param>

    <!-- Servlet context listeners that load the application blocks -->

    <listener>
        <listener-class>
            com.vaadin.server.communication.JSR356WebsocketInitializer
        </listener-class>
    </listener>
    <listener>
        <listener-class>
            com.haulmont.cuba.core.sys.singleapp.SingleAppCoreServletListener
        </listener-class>
    </listener>
    <listener>
        <listener-class>
            com.haulmont.cuba.web.sys.singleapp.SingleAppWebServletListener
        </listener-class>
    </listener>
</web-app>