Supply-Side Platform (SSP), Ad Exchange and Prebid Adapter Development

FatTail partnered with Clearcode to design and build their AdBookPSP solution — the first SSP designed specifically for deal-based programmatic transactions.

Below is an overview of our partnership with FatTail and details about the AdTech platform, components, and integrations we created during the project.


Tech company


Programmatic advertising


AdTech & programmatic


United States

About the project

FatTail and Clearcode joined forces to combine FatTail’s expertise in deal-based (direct) transactions, FatTail’s existing supply-side technology (AdBook+), Clearcode’s expertise in programmatic technology, and Clearcode’s experienced AdTech developers to build a first-of-its-kind SSP, or as we like to say, a premium supply platform (PSP). This platform is known as AdBookPSP and it specializes in deal ID-based programmatic transactions.

We believe this solution is timely for the market as increasing privacy restrictions across many fronts continue to erode identity resolution, thereby limiting buyer audience-driven programmatic strategies and creating increased demand for direct transactions with premium publishers.

Key points


In combination with FatTail’s AdBook+ platform, the AdBookPSP solution represents the first SSP designed specifically for deal-based programmatic transactions.


The various components of the solution included an ad exchange, FatTail’s official Prebid adapter, the programmatic lab environment for demand simulation and business testing, a reporting service, customized creative JavaScript, and integrations with DSPs, Google Ad Manager, and FatTail’s AdBook+ platform.

Main challenges

The main challenges were adjusting the Prebid adapter to send all the bids from the demand sources to Google Ad Manager instead of the default of 3 and learning about the integration process with Google Ad Manager.


The main technologies we used were Node.js, Nest.js, GO, React.js, Material UI, Azure (DataBricks and Blob), Kubernetes, Terraform, and Grafana.

“We chose Clearcode for their experience with header bidding technology and that expertise proved valuable in the implementation of our system.”

Gerry Bates


The Goal

FatTail and Clearcode joined forces to build a first-of-its-kind SSP, or as we like to say, a premium supply platform (PSP).

Main challenges

Adjusting the Prebid adapter

Adjusting the Prebid adapter to send all the bids from the demand sources to GAM instead of the default of 3 was the biggest challenge.

We had to change the character string to include all of the bids from the demand sources. Also, adapting FatTail’s Prebid Adapter to replace the key value pairs in a way that would allow us to integrate with GAM was also a challenge.

We also had to create each line item separately for the private auction workflow, which was a lot of manual work. We had to do this manually, but AdBook+ will automate this process for publishers on live deals. This challenge is inherent to the way Prebid is integrated with the GAM ad server to pass through programmatic demand.

Learning about configuring Google Ad Manager 

It was a new experience for us, but it was just a matter of learning about how to integrate with GAM and configure and match key value pairs like line items.

What we did

    • Ad exchange

      Designed and built AdBookPSP (an ad exchange).

    • Data from PMPs

      Ingested deal data from AdBook+

    • Prebid adapter

      Built FatTail’s official Prebid adapter.

    • Lab environment

      Built the programmatic lab environment for business testing.

    • Integrations

      Set up integrations with EngageBDR and RTBiQ.

    • Reporting

      Built a reporting service.

    • Decisioning logic

      Developed customized JavaScript and logic for creative execution on winning deal-based bids.

    Key components


    AdBookPSP is an exchange where the impressions from the Prebid adapter are matched with deals from AdBook+ and passed along as bid requests to the integrated DSPs. The exchange then processes responses and sends them via Prebid to GAM.

    In a traditional setup, an SSP issues bid requests, an auction is held, and the winning bid is chosen. With FatTail’s AdBookPSP, there could be multiple deal types at play, including programmatic guaranteed, preferred deal, and private action deals all competing alongside open market programmatic and direct deals in a publisher’s ad server.

    This created complexities for passing data back to Prebid & GAM as well as for retrieving the winning creative (downstream) from one of any number of bids received (upstream). The challenge here was to process bid responses and send back a batch of signals which appropriately reflect the demand engagement across multiple deals to GAM for final decisioning.

    We solved this challenge by taking deal instructions from AdBook+, running real-time processing, integrating with the DSPs, performing decisioning, and then facilitating post-RTB processing.


    By default, Prebid only collects the highest bid from the connected SSPs.

    Since AdBookPSP supports running multiple simultaneous deals of different deal types and varying priority levels, the auction clearing process cannot be performed on price alone. Following some post-processing after bid responses are collected, AdBookPSP must pass signals to GAM reflecting the demand received from DSPs for final decisioning.

    The challenge then became about how AdBookPSP works through Prebid as a header bidding layer to deliver those signals to GAM. We solved this by conducting research and applying problem-solving methods to craft an appropriate key-value signaling strategy and use the “sendAllBids” method in Prebid to send all relevant bids from the various deals to GAM.

    Programmatic lab environment

    We built the programmatic lab environment for business and performance testing.

    FatTail can set up all the same components that they have in the production environment but with mock DSPs and websites.

    FatTail can also create their own deal files, scenarios, and upload creatives — everything that you would have in the live environment.

    Private auction workflow (aka private marketplace)

    This was very similar to the programmatic guarantee setup that we created. It was just essentially another auction, but instead of sending all bids, we just sent the highest bid across all deals assigned to this workflow.

    Reporting services

    The reporting service runs via APIs. We didn’t build a UI for this, we just exposed an endpoint. In the future it will be integrated with AdBook+.

    A word from FatTail

    FatTail engaged Clearcode to help us implement a new component in our AdBook+ system — AdBook Premium Supply Platform (AdBookPSP). We chose Clearcode for their experience with header bidding technology and that expertise proved valuable in the implementation of our system. Clearcode has a well-structured process for discovery that allows for collaboration on all requirements of the project. 

    During the implementation phase, the team was easy to work with and we are happy with the solutions they delivered in terms of performance, scalability, and long-term maintenance of the system. When the team completed the project, they supplied FatTail with all the necessary documentation on all aspects of the system and were available for questions to support the launch of the system. 

    It was a pleasure collaborating with the Clearcode team and we’re looking forward to working with them on future initiatives.

    Gerry Bates, CTO at FatTail

    The technologies we used








    Material UI

    The result

    We built the AdBookPSP and handed the project over to Fattail so they could start testing it with their clients.

    We are still providing Fattail with support and maintenance of the platform, as well as working on other projects with them.