Compile the Digital Garage Keyword Module and Appnexus Bid Adapter into your Prebid build:
 gulp build --modules="dgkeywordRtdProvider,appnexusBidAdapter,..."  
Use setConfig to instruct Prebid.js to initilize the dgkeyword module, as specified below.
This module is configured as part of the realTimeData.dataProviders
var DGKEYWORD_TIMEOUT = 1000;
pbjs.setConfig({
    realTimeData: {
        auctionDelay: DGKEYWORD_TIMEOUT,
        dataProviders: [{
            name: 'dgkeyword',
            waitForIt: true,
            params: {
                timeout: DGKEYWORD_TIMEOUT
            }
        }]
    }
});
Syntax details:
| Name | Type | Description | Notes | 
|---|---|---|---|
| name | String | Real time data module name | Always ‘dgkeyword’ | 
| waitForIt | Boolean | Should be trueif there’s anauctionDelaydefined (optional) | false | 
| params | Object | ||
| params.timeout | Integer | timeout (ms) | 1000 |