Shopify Theme Inspector

Shopify · Oct 20, 2020

How to Do an In-depth Liquid Render Analysis with Theme Inspector

Shopify theme code can create server-side rendering bottlenecks that leave customers waiting on a blank screen, so the article explains how to analyze Liquid performance with Shopify Theme Inspector. It describes flame graphs as representations of code paths and execution time, then compares clean Liquid with heavy loops, nested loops, and mixed global Liquid scopes. Accessing product attributes raised a 10-item example from 13 ms to 162 ms, while 50 products took 800 ms; two- and three-level nested examples rendered in 55 ms and 72 ms. The guidance recommends examining total iteration time, sawtooth or hair-comb patterns, unnecessary attributes, pagination size, and AJAX alternatives. It proposes aiming for 200 ms and keeping total page rendering under 500 ms, while noting that this alone does not guarantee a good LCP score.