A dashboard I built was taking 4+ seconds to load. Products, orders, inventory, customer data — each query waited politely for the one before it to finish. Classic sequential bottleneck.

The fix was parallelism. But naive parallelism on Shopify's GraphQL API gets you throttled fast, because it doesn't count requests — it counts cost. So I had to learn how to go parallel and stay under the rate ceiling.

This post is everything I wish I'd known before I started. Code included.

Why sequential queries are the silent killer

Picture a dashboard loading three things: