Tutorials

Hands-on, step-by-step guides for building change-driven applications with the @drasi/lib Node.js library.

  less than a minute  

Work through these tutorials to learn @drasi/lib by building complete, runnable applications. Each tutorial lives in tutorials/ and embeds the Drasi continuous-query engine directly in a Node.js app — real data sources, continuous queries, and reactions, with no separate server to run.

Getting Started

Your first steps with @drasi/lib — embed the Drasi engine in a Node console app, connect it to a live PostgreSQL message feed, and build five continuous queries (change detection, a filter, an aggregation, a time-based query, and a cross-source join) that print every change to your terminal.

Building Comfort

Monitor a smart building’s comfort in real time with PostgreSQL CDC, six continuous queries with synthetic joins, and an SSE reaction that shapes payloads with Handlebars to drive a live web UI.

Curbside Pickup

Build a real-time view over two different databases — a PostgreSQL orders store and a MySQL vehicles store — joined by license plate, with an embedded Drasi engine, an SSE reaction that shapes payloads with Handlebars, and one integrated web UI that both drives the changes and shows them live.