Many applications struggle with slow API responses, heavy JSON payloads, and backend bottlenecks—especially when data needs filtering, grouping, or aggregation on the fly. For teams using Azure Cosmos DB, these patterns often lead to costly RU spikes and over-engineered backend endpoints.

This session introduces a modern alternative. You’ll learn how Cosmos DB Mirroring streams operational data into Microsoft Fabric OneLake as compressed Delta Parquet files without consuming production RUs. Using the Fabric SQL Endpoint, you’ll see how to retrieve that data and return it to the browser through a Parquet-first API instead of JSON.

Then the fun begins. Attendees will see how DuckDB‑Wasm can load those Parquet files directly in the browser and run fast SQL queries — joins, pivots, aggregates — entirely client‑side. No backend compute. No RU spikes. No JSON overhead.

In one session, you’ll learn how to combine Cosmos DB, Fabric, Parquet, and DuckDB‑Wasm to build faster, simpler, and more scalable data‑driven applications.