Jib is a build plugin for Maven and Gradle that packages Java applications into container images directly within the build lifecycle. By integrating into the standard build process, it eliminates the need for Dockerfiles or a local container daemon to create and store images.
The tool constructs images by organizing application artifacts into distinct filesystem layers, which improves cache efficiency and reduces data transfer during registry pushes. It communicates directly with container registries using standard protocols and supports credential helper orchestration to manage authentication for private environments.
The build process enforces reproducibility by stripping timestamps and maintaining consistent file ordering, ensuring that identical source inputs consistently produce the same image output. This approach enables container image construction in restricted environments, such as continuous integration pipelines, where a full container runtime is unavailable.