Exa launched Snapshot. It lets users search the web as it existed on any past date. The feature uses over 400 billion webpage snapshots spanning two decades. It prevents web leakage in agent training by excluding later-published solutions. It also enables backtesting in finance using only information available on a given day. Users set a date via the `snapshotAsOf` parameter in the search and contents APIs. It is currently a research preview. Full details are in the documentation.

• 400 billion webpage snapshots
• 2 decades of coverage