moby/buildkit

BuildKit is a toolkit for converting source code to build artifacts in an efficient, expressive and repeatable manner.

BuildKit addresses the problem of slow and inefficient container image builds by providing concurrent dependency resolution, efficient instruction caching, and automatic garbage collection. Its approach centers on a pluggable architecture that decouples the build logic from the frontend format, allowing it to work with Dockerfiles and other build specifications through interchangeable frontends. The toolkit supports nested build job invocations, distributable workers, and multiple output formats including OCI images, Docker tarballs, and local directories. It can execute builds without requiring root privileges and includes built-in support for advanced Dockerfile features like mount types for bind, cache, tmpfs, secret, and SSH.

Developers should choose BuildKit if they need faster, more efficient builds with fine-grained caching control or if they require builds to run in restricted environments without root access. It suits projects that benefit from concurrent builds, need to distribute build work across multiple workers, or require integration with container orchestration platforms like Kubernetes. The tool is particularly valuable for CI/CD pipelines where build cache efficiency directly impacts throughput. Since Docker Engine version 23.0, the standard docker build command uses BuildKit by default through Buildx, though the standalone version offers additional capabilities for advanced use cases.

The project maintains active development with regular contributions addressing core functionality and new features. The codebase shows ongoing work on cache management systems, including support for multiple cache backends such as registry, local directory, GitHub Actions cache, S3, and Azure Blob Storage. Development includes infrastructure improvements like OpenTelemetry support for observability and systemd socket activation for deployment flexibility. The project sustains a community channel and accepts external contributions, with documentation covering setup across Linux, Windows, and macOS platforms as well as containerized deployment scenarios.