Add the network's bidder to your own Prebid.js

For a publisher who already runs Prebid.js — build in the epom_as adapter, add the bids entry the network sent to each ad unit, run the alias line if there is one and keep a single auction, with the video cache note, where the adapter comes from and what to check when a position never shows network demand.

How-to publisher

What it is and why

Your pages already run Prebid.js, and your network joins the auction as one more bidder: it sends one bids entry per ad unit (and an alias line, if it bids under its own name), and you add them next to your other bidders. Your ad units, sizes and other bidders stay as they are. There is no Epom SDK — Epom takes part as an ordinary Prebid bidder called epom_as. The other setups are on Header bidding: what a publisher installs.

Example. An ad unit article-leaderboard with sizes 728×90 and 970×90 gets a second bids object — bidder: 'epom_as' with the network’s networkId, host and placementKey. On each page view the network’s campaigns compete with the unit’s other bidders; when they win, their creative renders in that unit, in one of its listed sizes.

Typical scenarios

How your pages serve ads today	What the network sends you	Where it goes
Your own Prebid.js	One `bids` entry per ad unit (and an alias line, if the network bids under its own name)	Your Prebid configuration
Your own Prebid.js with video units	The same, plus a cache setting on your side	Your Prebid configuration

Step by step

Make sure your Prebid.js build includes the epom_as bidder adapter — see Getting the adapter.

Add each bids entry to the existing ad unit it names — an extra object in that unit’s bids array, next to your other bidders. Keep your mediaTypes, sizes and other bidders unchanged. With the values the network sent, an ad unit looks like this:

pbjs.addAdUnits([{
  code: 'article-leaderboard',                      // your ad unit, unchanged
  mediaTypes: { banner: { sizes: [[728, 90], [970, 90]] } },
  bids: [
    { bidder: 'yourOtherBidder', params: { /* unchanged */ } },
    {
      bidder: 'epom_as',
      params: {
        networkId: 'n1234',                         // your network
        host: 'ads.example.com',                    // the network's serving domain
        placementKey: 'a4f21c9e7b'                  // the placement for this position
      }
    }
  ]
}]);

Copy the values from what the network sent rather than typing them (the parameters are under Reference on the hub). If the network bids under its own name, the entry’s bidder is that name (for example epom_n1234) instead of epom_as, and the alias line in the next step comes with it.

The network's Code face for a page that already runs Prebid.js: the per-slot bids entry

If the network sent an alias line (pbjs.aliasBidder('epom_as', '…')), run it once per page before the auction; rename pbjs if your Prebid uses another global.
Run your auction as usual. Do not add a second wrapper or the network’s own script beside your Prebid: two auctions on the same ad units overwrite each other’s results.

For video units, your Prebid needs a cache setting or it drops the network’s VAST bids before your bidsBackHandler runs; see Instream video under What the publisher does with it.

Getting the adapter

You need the epom_as adapter only when the auction runs in your own Prebid.js or your own Prebid Server. With the network’s script, or with the Prebid Server address the network sends, there is nothing to add.

The adapter is Epom’s and is not in the standard Prebid.js download or in a released Prebid Server build. It has been submitted to the Prebid projects and is under review; until it is released there, you get it from your network, which gets it from Epom:

Prebid.js — the module to add to your own build, or a ready build that carries it.
Prebid Server — your server has to be built with the adapter. Ask your network; Epom helps with the setup.

The epom_dsp adapter in the standard download is a different Epom product, for buying media, and cannot take part in these auctions.

Caveats and exceptions

In your own Prebid, a creative bids only in a size your ad unit lists. If an ad unit never shows Epom demand, check that its mediaTypes.banner.sizes include the sizes the network sells there.

The caveats that apply to every setup — who this is for, what you need before you start, the floors and consent you keep, how changes reach the page — are on Header bidding: what a publisher installs.

Not working?

A position never shows network demand (own Prebid.js). Where: that ad unit’s mediaTypes.banner.sizes against the sizes the network sells; the bids entry’s networkId, host (bare hostname, no https://, no path) and placementKey against what the network sent; whether the alias line runs before the auction.
Two wrappers on the page. Where: the page source — the network’s script beside your own Prebid runs two auctions on the same units and each overwrites the other’s results; keep one.
Video bids vanish before bidsBackHandler. Where: your Prebid’s cache setting — see Instream video under What the publisher does with it.

The causes common to every setup (currency floors, the consent stub, the missing tab) are on Header bidding: what a publisher installs.

Reference

The bids entry’s parameters — networkId, host, placementKey, channel, customParams, bidFloor / bidFloorCur — are the table under Reference on the hub. The network’s side of this setup: Header bidding on a site that runs its own Prebid.js.