Cloud Native Buildpacks Pack vs rules_docker

Cloud Native Buildpacks Pack is a free command-line tool for building applications with buildpacks and rebasing the resulting application images. It is maintained by the Cloud Native Buildpacks project and is also available as a Go library. Buildpacks turn application source code into container images that can run on any cloud. Listed capabilities include caching, automatic source detection, modular buildpacks, support for multiple languages and processes, minimal images, reproducible builds and reuse of community buildpacks. Pack supports multi-architecture builds and multiple build-cache backends, and the project lists build-time software bills of materials in CycloneDX, SPDX and Syft JSON formats. The CLI runs on Linux, macOS and Windows; installation options include package managers, container images, scripts and manual installation. Builds need a containerized environment and a daemon such as Docker or Podman, and some setups may need the local Docker socket mounted. The project documents CircleCI, GitLab Auto DevOps and Tekton integrations, as well as kpack for Kubernetes-native builds and image updates. Pack is Apache-2.0 licensed.

rules_docker has no write-up on Specifiction yet; its figures are above.