prebundle

Prebundle is a software packaging technique in which a set of code components, typically dependencies, is bundled into a single artifact before the main build or at build time. The goal is to reduce future build times, improve startup performance, or simplify deployment by separating stable, frequently used code from rapidly changing parts of an application. The prebundle artifact is consumed by the main bundle during the build process or loaded at runtime, depending on the environment.

In practice, prebundling is common in modern web development, where bundlers may produce a separate vendor or prebundle chunk that includes third-party libraries that change infrequently. This can lessen parsing, transformation, and network costs for subsequent builds and can be cached by tools and environments, speeding up development and deployment cycles.

Implementation approaches vary. They may involve a dedicated bundling step that precompiles and bundles chosen dependencies, storing the result in a versioned artifact. Some pipelines cache the prebundle and reuse it across builds, refreshing it only when dependencies change. Prebundles may also appear in native module ecosystems, where prebuilt components reduce installation or startup overhead.

Considerations include maintaining synchronization between the prebundle and the main application, ensuring cache invalidation when dependencies update, and weighing the added maintenance burden against the performance gains. Developers should assess whether the stability of dependencies, build tooling, and deployment targets justify introducing a prebundle in their workflow.