Prebid.js is the wrapper most of the open web runs on. This track takes you from the wrapper concept through ad units, adapters, the auction lifecycle, timeouts, price granularity, GAM line items, and the module system. The Prebid config analyzer in Bidcliq Academy is the live companion.

1. L2B1What Prebid.js is and the wrapper concept

   Prereqs: A3

   Objectives

   • Define a wrapper / container tag.
   • Explain why publishers use a managed wrapper instead of stacking N vendor tags.
   • Identify Prebid.js as the dominant open-source wrapper and its component model: core plus bid adapters plus analytics adapters plus modules.

   Key concepts

   Wrapper / container tagPrebid.js component model (core, bid adapters, analytics adapters, modules)Managed vs unmanaged multi-tag setups

   Assessment

   Annotate the four Prebid.js component types and explain one risk of an unmanaged multi-tag setup.

   Read the lesson →

   PRACTICE

   Proposed guided "build a Prebid.js bundle" config exercise.

2. L2B2Ad units and the OpenRTB shape of a request

   Prereqs: B1

   Objectives

   • Author an adUnit: code, mediaTypes (banner / video / native), sizes / sizeConfig, bids[].
   • Map ad-unit fields to the OpenRTB imp object.
   • Understand ortb2 / ortb2Imp first-party data.

   Key concepts

   adUnit (code, mediaTypes, sizes, bids[])OpenRTB imp mappingortb2 / ortb2Imp first-party data

   Assessment

   Write a valid two-bidder banner ad unit from a spec, then find the bug in a malformed one.

   Read the lesson →

   PRACTICE

   Proposed ad-unit builder.

   DEBUG

   Proposed "no bids because the size was never requested" reproduction.

3. L2-L3B3Bidder adapters and bidder params

   Prereqs: B2

   Objectives

   • Explain what a bid adapter does.
   • Configure per-bidder params.
   • Understand aliases.

   Key concepts

   Bid adapterPer-bidder params (placement / zone / site IDs)Aliases

   Assessment

   Fill the correct params from a bidder's docs and explain why a copied param block fails for another bidder.

   Read the lesson →

   ANALYZE

   Each bidder in a Prebid config should map to an authorized line in the publisher ads.txt. Cross-check a config against a Bidcliq Academy audit and flag any bidder with no authorization, a real and common leak. Start from the Prebid analyzer.

   Open the Prebid analyzer →

   DEBUG

   UNAUTHORIZED root-caused to "bidder live in the wrapper but absent from ads.txt."

   Run it live →
4. L3B4The auction lifecycle and bidsBackHandler

   Prereqs: B2, B3

   Objectives

   • Sequence the auction: requestBids() fires adapters in parallel, responses are collected, bidsBackHandler fires on all-back or timeout, then targeting is set and the ad server is called.
   • Use the Prebid event system.

   Key concepts

   requestBids()bidsBackHandler (all-back or timeout)setTargetingForGPTAsync()The Prebid event system

   Assessment

   Order a scrambled lifecycle, explain timedOut: true, and write a bidsBackHandler that calls setTargetingForGPTAsync() then refresh.

   Read the lesson →

   DEBUG

   Proposed auction-timeline simulator.

5. L3B5Timeouts

   Prereqs: B4

   Objectives

   • Distinguish the auction timeout, bidderTimeout, and failsafeTimeout.
   • Explain the revenue trade: too short starves bids, too long delays the ad-server call.
   • Understand that setTimeout is not a hard guarantee.

   Key concepts

   bidderTimeoutfailsafeTimeoutThe latency-vs-bid-density trade

   Assessment

   Given a latency histogram, choose a timeout that captures the 80th percentile without exceeding a page-experience budget.

   Read the lesson →

   DEBUG

   Proposed timeout-tuning sandbox.

   PRACTICE

   Proposed failsafe proof.

   ANALYZE

   See how the Prebid analyzer flags a too-low or too-high bidderTimeout on a real config.

   Open the Prebid analyzer →
6. L3B6Price granularity, bucketing, and targeting key-values

   Prereqs: B4

   Objectives

   • Explain why bids are quantized into price buckets.
   • Configure standard vs custom priceGranularity.
   • Map winning bids to hb_pb, hb_adid, hb_size, hb_format, and per-bidder variants under send-all-bids.
   • Understand query-string length risk.

   Key concepts

   Price bucketsStandard vs custom priceGranularityhb_pb / hb_adid / hb_size / hb_formatSend-all-bids key explosion

   Assessment

   Define a custom bucket scheme and compute the keys produced for a given winning bid.

   Read the lesson →

   PRACTICE

   Proposed granularity designer.

   DEBUG

   Proposed "bid lost revenue to a coarse bucket" reproduction.

7. L3-L4B7GAM line-item setup

   Prereqs: B6

   Objectives

   • Build the GAM scaffold: key-values, Price Priority (type 12) line items per bucket, the universal creative.
   • Choose top-price vs send-all-bids trafficking and reason about UPR (Unified Pricing Rules) interaction.

   Key concepts

   Price Priority line items (type 12)Universal creativeTop-price vs send-all-bids traffickingUnified Pricing Rules (UPR)

   Assessment

   Compute the line-item count for a granularity, write key-value targeting for a $4.50 line item, and explain a missing-key failure mode.

   Read the lesson →

   PRACTICE

   Proposed line-item generator.

   DEBUG

   Proposed "creative renders blank because hb_adid is undefined in GAM" reproduction.

8. L3B8Modules, analytics adapters, and config (setConfig)

   Prereqs: B4

   Objectives

   • Navigate the module system: User ID, floors, consent, currency, and analytics.
   • Use setConfig() and bidderSettings (CPM adjustments, custom targeting).
   • Wire one analytics adapter.

   Key concepts

   The module systemsetConfig()bidderSettings and bidCpmAdjustmentAnalytics adapters

   Assessment

   Configure a 10% bidCpmAdjustment and explain its competitive effect, then list the modules for a GDPR-compliant, floored, UID2-enabled build.

   Read the lesson →

   PRACTICE

   Proposed config composer.

   ANALYZE

   Paste a setConfig block into the Prebid analyzer to see which modules (consent, schain, floors, identity) are present.

   Open the Prebid analyzer →