Render-blocking resources are JavaScript and CSS files that prevent the web page from loading until they are downloaded. These might be critical resources that don’t get loaded immediately, or non-critical resources that are being loaded at the very beginning. Fixing render-blocking JavaScript and CSS helps improve page load times so sneakerheads don’t bounce to your competitor’s site while waiting for the images of the latest drop to load.

Modern applications are complex inter-connected collections of services and moving parts that all have the potential to fail or not work as expected. Flutter and the language it’s built upon, Dart, are designed for event-driven, concurrent, and, most crucially, performant apps. It’s important for any developer using them to have a decent selection of debug tools.

There’s only so much you can control when it comes to your app’s performance. But you control what is arguably most important - the code. Sentry Performance gets you the code-level insights you need to resolve performance bottlenecks.

If you’re a front end developer, there’s a high probability you’ve built (or will build) an image-heavy page. And you’ll need to make it look great by serving high-quality image files. But you’ll also need to prioritize building a high-quality user experience by making sure your Core Web Vitals such as Cumulative Layout Shift and Largest Contentful Paint aren’t negatively affected, which also help with your search engine rankings.

Knowing what issues to hit the snooze button on, or drop everything and push a hotfix for is a common developer dilemma. Similarly to what was discussed in Sleep More; Triage Faster with Sentry, we’ve been collecting and iterating on customer feedback for ways to reduce issue noise and surface high-priority issues faster.

A stack trace lacking your source code with all the variables and function names, is like putting together a jigsaw puzzle without a picture for reference. You have all these randomly shaped pieces but no way to know how they fit together. Unless you are fluent in computer, making sense of a JavaScript stack trace with minified code is going to make debugging very difficult. Thankfully, by uploading source maps to Sentry, you can map back to the original source code to make sense of what went wrong.