LABjs is a lightweight JavaScript loader focused on speeding up page performance by controlling how and when scripts download and execute. It provides an expressive API to load multiple files in parallel while guaranteeing execution order, so dependent scripts don’t break. By decoupling fetch from execute, it avoids the blocking behavior of traditional tags and helps reduce perceived load time. LABjs embraces a “load groups, then wait” model that makes dependency management clear without a separate build step. It’s designed to work across a wide range of browsers, including older ones, which is why it relies on robust feature detection and time-tested loading techniques. The library is intentionally small and framework-agnostic, so it can be dropped into almost any stack to orchestrate client-side assets more predictably.
Features
- Parallel downloading with ordered execution for dependent scripts
- Simple chainable API to group scripts and insert wait points
- Non-blocking loading to improve first render and interactivity
- Works without bundlers or frameworks and coexists with them if present
- Graceful behavior across legacy and modern browsers
- Optional cache-busting and dynamic URL construction patterns