Autotrader's identity stitching ran as a batch job that could run at most once an hour, but its personalization runs in real time. To close that gap, the team spent a month building their own real-time version in Spark while trialing Snowplow Identities side by side.
Their own build reached tens of seconds but was complex to write and maintain. Snowplow Identities runs inside the Snowplow pipeline Autotrader already uses, so it processed events in milliseconds, and Snowplow handles the identity graph logic instead of Autotrader's developers.
From the talk "Build or buy: real-time identity resolution at Autotrader", recorded at Big Data London 2026.
Watch the full talk: https://snowplow.io/events/build-or-buy-real-time-identity-resolution-at-autotrader