List, inspect and explore OCI container images, their layers and contents

Summary

cek Explore OCI container images without running them. cek is a command-line utility for filesystem exploration inside OCI container images. It focuses on browsing files, reading contents, and inspecting layer mechanics—without running containers. cek reads images directly from local container daemons (Docker, Podman, containerd, etc.) or pulls them from remote registries. cek runs without root privileges and works with any OCI-compliant image registry. While it does not require a container daemon, it can leverage one when available to access locally cached images and avoid registry rate limits. Most importantly, cek never runs containers. Installation go install github.com/bschaatsbergen/cek@latest Or build from source: git clone https://github.com/bschaatsbergen/cek.git cd cek go build -o cek . Usage Inspect image metadata View image details including digest, creation time, architecture, total size, and individual layer information. cek inspect nginx Image: nginx Registry: index.docker.io Digest: sha256:ec0ee8695f2f71addca9b40f27df0fdfbde460485a2b68b834e18ea856542f1e Created: 2025-12-09T22:50:18Z OS/Arch: linux/arm64 Size: 55.6 MB Layers: # Digest Size 1 sha256:f626fba1463b32b20f78d29b52dcf15be927dbb5372a9ba6a5f97aad47ae220b 28.7 MB 2 sha256:89d0a1112522e6e01ed53f0b339cb1a121ea7e19cfebdb325763bf5045ba7a47 26.8 MB 3 sha256:1b7c70849006971147c73371c868b789998c7220ba42e777d2d7e5894ac26e54 627 B 4 sha256:b8b0307e95c93307d99d02d3bdc61c3ed0b8d26685bb9bafc6c62d4170a2363e 954 B 5 sha256:fe1d23b41cb3b150a19a697809a56f455f1dac2bf8b60c8a1d0427965126aaf9 403 B 6 sha256:fda1d961e2b70f435ee701baaa260a569d7ea2eacd9f6dba8ac0320dc9b7d9fe 1.2 KB 7 sha256:10dbff0ec650f05c6cdcb80c2e7cc93db11c265b775a7a54e1dd48e4cbcebbbc 1.4 KB List files in an image By default, cek ls shows the merged overlay filesystem, which is what you see inside a running container. All layers are combined, with upper layers overriding lower ones. You can optionally specify a path to list only files under a speci...