ZCML File
configure.zcml

<configure
    xmlns="http://namespaces.zope.org/browser"
    xmlns:help="http://namespaces.zope.org/help"
    xmlns:zcml="http://namespaces.zope.org/zcml"
    xmlns:zope="http://namespaces.zope.org/zope"
    i18n_domain="zope"
    >
<layer
    name="boston"
    interface="zope.app.boston.boston"
    bbb_aware="true"
    zcml:condition="have deprecatedlayers"
    />
<zope:interface
    interface="zope.app.boston.Boston"
    type="zope.publisher.interfaces.browser.IBrowserSkinType"
    name="Boston"
    />
<viewletManager
    layer="zope.app.boston.boston"
    permission="zope.Public"
    name="zope.app.boston.IHead"
    provides="zope.app.boston.IHead"
    />
<viewletManager
    layer="zope.app.boston.boston"
    permission="zope.Public"
    name="zope.app.boston.ICSS"
    provides="zope.app.boston.ICSS"
    />
<viewletManager
    layer="zope.app.boston.boston"
    permission="zope.Public"
    name="zope.app.boston.IJavaScript"
    provides="zope.app.boston.IJavaScript"
    />
<viewletManager
    class=".viewlets.toolbar.browser.ToolBarViewletManager"
    layer="zope.app.boston.boston"
    permission="zope.Public"
    name="zope.app.boston.IToolBar"
    template="viewlets/toolbar/macros.pt"
    provides="zope.app.boston.IToolBar"
    />
<viewletManager
    class="zope.app.boston.LeftViewletManager"
    layer="zope.app.boston.boston"
    permission="zope.Public"
    name="zope.app.boston.ILeft"
    provides="zope.app.boston.ILeft"
    />
<include
    package=".viewlets"
    />
<include
    package=".browser"
    />
<configure
    zcml:condition="have onlinehelp"
    >
<help:register
    id="boston"
    title="Boston Skin"
    doc_path="README.txt"
    class="zope.app.onlinehelp.onlinehelptopic.RESTOnlineHelpTopic"
    />
</configure>
</configure>