A Containerfile is a plain text file that contains instructions for building container images. It is fully compatible with Docker's Dockerfile format and is the default file name used by Buildah and Podman. Containerfile instructions describe a base image (FROM), the steps to assemble the image (RUN, COPY, ADD, ARG, ENV), and runtime defaults (CMD, ENTRYPOINT, EXPOSE, USER, WORKDIR, VOLUME). Modern build engines extend the format with cache, secret, and SSH mounts and with platform-aware multi-stage builds.
Containerfile publishes 4 APIs on the APIs.io network. Tagged areas include BuildKit, Buildah, Containers, DevOps, and Docker.
Containerfile’s developer surface includes documentation and 13 more developer resources.
Open Source Surface applies to this provider. This product is open source and we
read its repository directly, so Open Source Surface carries
10 points of the composite. It is scored from what the repository actually
publishes — a security policy, a contribution guide, a release history, a code of conduct — read live from the
provider rather than inferred from our own catalog pointers.
This facet adds; nothing was taken away to make room for it. An open-source project is not excused from
the commercial facets, because exemption would strip it of the points it does earn.
If we have the wrong repository, or this product is not open source, say so on your
provider repo and we
will drop the facet rather than have you publish against it.
Create-or-Update Ergonomics could not be measured. We hold no machine-readable contract for
this provider to read, so there is nothing to measure a write surface against. Excluded rather than scored zero:
never-measured and measured-empty are different facts. Publishing an OpenAPI is what makes this facet — and
several others — scorable at all.
The six quality facets above are damped to 90 points between them,
because the conditional facet above carries the other
10. That is why each facet's contribution is shown against a damped
maximum: raising a quality facet moves the composite by 90% of its nominal
weight, not 100%. The full arithmetic is at apis.io/rating/.
The official Containerfile reference shipped with the containers/common project. Documents every Containerfile instruction, syntax, and the ways Containerfile differs from Docke...
The Dockerfile format reference maintained by Docker. Containerfile is a strict superset of Dockerfile, so the Dockerfile reference covers the same instruction set with Docker-s...
Dockerfile and Containerfile parsing in modern Docker is performed by BuildKit's Dockerfile frontend, distributed as a container image (docker/dockerfile). The frontend version ...
The Open Container Initiative Image Specification defines the format of the image artifacts that Containerfile and Dockerfile builds produce. The spec covers manifests, configur...
aid: containerfile
url: https://raw.githubusercontent.com/api-evangelist/containerfile/refs/heads/main/apis.yml
name: Containerfile
kind: standard
description: A Containerfile is a plain text file that contains instructions for building container images. It is fully compatible
with Docker's Dockerfile format and is the default file name used by Buildah and Podman. Containerfile instructions describe
a base image (FROM), the steps to assemble the image (RUN, COPY, ADD, ARG, ENV), and runtime defaults (CMD, ENTRYPOINT,
EXPOSE, USER, WORKDIR, VOLUME). Modern build engines extend the format with cache, secret, and SSH mounts and with platform-aware
multi-stage builds.
deliveryModel:
model: self-hosted
license: Apache-2.0
open_source: true
commercial: false
callable_host: false
label: Self-hosted open source · you run it yourself
confidence: high
source:
- license
generated: '2026-08-28'
method: derived
accessModel:
pricing: freemium
onboarding: unknown
trial: false
try_now: false
public: false
label: Freemium
confidence: medium
source:
- plans
generated: '2026-07-22'
method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/containerfile.png
tags:
- BuildKit
- Buildah
- Containers
- DevOps
- Docker
- Dockerfile
- Image Build
- OCI
- Podman
- Standard
created: '2025-01-01'
modified: '2026-04-28'
specificationVersion: '0.23'
apis:
- aid: containerfile:reference
name: Containerfile Reference
description: The official Containerfile reference shipped with the containers/common project. Documents every Containerfile
instruction, syntax, and the ways Containerfile differs from Dockerfile, including secret mounts and platform-aware ARGs.
humanURL: https://github.com/containers/common/blob/main/docs/Containerfile.5.md
baseURL: https://github.com
tags:
- Containerfile
- Reference
- containers/common
properties:
- type: Specification
url: https://github.com/containers/common/blob/main/docs/Containerfile.5.md
- type: Documentation
url: https://docs.podman.io/en/latest/markdown/podman-build.1.html
- type: GitHubRepository
url: https://github.com/containers/common
x-features:
- Documents FROM, RUN, COPY, ADD, ARG, ENV, CMD, ENTRYPOINT, EXPOSE, USER, WORKDIR, VOLUME, LABEL, ONBUILD
- RUN --mount support for bind, cache, secret, ssh, and tmpfs mounts
- Platform-aware ARGs (TARGETARCH, TARGETOS, TARGETPLATFORM, BUILDARCH, BUILDOS, BUILDPLATFORM)
- HEREDOC syntax for inline RUN scripts
- Multi-stage builds via FROM ... AS name
x-useCases:
- Authoring portable Containerfiles for Podman and Docker
- Migrating between Docker and Podman build tooling
- Defining cross-platform images with multi-arch support
- aid: containerfile:dockerfile-reference
name: Dockerfile Reference
description: The Dockerfile format reference maintained by Docker. Containerfile is a strict superset of Dockerfile, so
the Dockerfile reference covers the same instruction set with Docker-specific extensions such as directives like syntax=
and check=.
humanURL: https://docs.docker.com/reference/dockerfile/
baseURL: https://docs.docker.com
tags:
- Docker
- Dockerfile
- Reference
properties:
- type: Specification
url: https://docs.docker.com/reference/dockerfile/
- type: Documentation
url: https://docs.docker.com/build/
- type: Reference
url: https://docs.docker.com/build/buildkit/
x-features:
- Authoritative Dockerfile reference for all instructions
- Directives such as syntax= and check= for builder behavior
- BuildKit-specific RUN --mount syntax
- Linting rules via the Dockerfile checker
x-useCases:
- Authoring Dockerfiles or Containerfiles for Docker BuildKit
- Looking up the exact syntax of an instruction or flag
- Adopting newer BuildKit features like SSH mounts
- aid: containerfile:buildkit-frontend
name: BuildKit Dockerfile Frontend
description: Dockerfile and Containerfile parsing in modern Docker is performed by BuildKit's Dockerfile frontend, distributed
as a container image (docker/dockerfile). The frontend version is selected via the `# syntax=` directive and adds new
features without requiring a BuildKit upgrade.
humanURL: https://github.com/moby/buildkit/blob/master/frontend/dockerfile/docs/reference.md
baseURL: https://github.com
tags:
- BuildKit
- Frontend
- Moby
properties:
- type: Documentation
url: https://github.com/moby/buildkit/blob/master/frontend/dockerfile/docs/reference.md
- type: GitHubRepository
url: https://github.com/moby/buildkit
- type: Reference
url: https://hub.docker.com/r/docker/dockerfile
x-features:
- Versioned Dockerfile frontend images
- Pluggable parser via `# syntax=` directive
- Adds RUN --mount, secret, ssh, and cache features
- Used by docker buildx and BuildKit-based builders
x-useCases:
- Pinning the Dockerfile frontend version for reproducibility
- Adopting new RUN features without upgrading the daemon
- Authoring Dockerfile linting rules and tools
- aid: containerfile:oci-image-spec
name: OCI Image Specification
description: The Open Container Initiative Image Specification defines the format of the image artifacts that Containerfile
and Dockerfile builds produce. The spec covers manifests, configuration, layers, and indexes consumed by container runtimes
such as runc, crun, and containerd.
humanURL: https://github.com/opencontainers/image-spec
baseURL: https://github.com
tags:
- Image
- OCI
- Standards
properties:
- type: Specification
url: https://github.com/opencontainers/image-spec
- type: GitHubRepository
url: https://github.com/opencontainers/image-spec
- type: Reference
url: https://opencontainers.org/
x-features:
- Image manifest, configuration, and layer schema
- Image index for multi-platform images
- Foundational spec for OCI registries and runtimes
x-useCases:
- Building tools that produce OCI images directly
- Verifying that Containerfile output conforms to OCI
- Implementing multi-arch image manifests
common:
- type: IssueTracker
url: https://github.com/containers/common/issues
- type: Releases
url: https://github.com/containers/common/releases
- type: SecurityPolicy
url: https://github.com/containers/common/blob/main/SECURITY.md
- type: CodeOfConduct
url: https://github.com/containers/common/blob/main/CODE-OF-CONDUCT.md
- type: ContributionGuide
url: https://github.com/containers/common/blob/main/.github/CONTRIBUTING.md
- type: License
name: Apache-2.0
url: https://github.com/containers/common/blob/main/LICENSE
- type: VulnerabilityDisclosure
url: security/containerfile-vulnerability-disclosure.yml
- type: DomainSecurity
url: security/containerfile-domain-security.yml
- type: Specification
url: https://github.com/containers/common/blob/main/docs/Containerfile.5.md
- type: Documentation
url: https://docs.docker.com/reference/dockerfile/
- type: Reference
url: https://github.com/moby/buildkit/blob/master/frontend/dockerfile/docs/reference.md
- type: Reference
url: https://opencontainers.org/
- type: GitHubOrganization
url: https://github.com/containers
- type: GitHubRepository
url: https://github.com/containers/buildah
maintainers:
- FN: Kin Lane
email: kin@apievangelist.com
Discovery needs no key. Ratings and market analysis are Pro.
Get an API key
Free tier, no form to fill in. Signing in shares your email address with us — we
store it to create your key and to recognise you if you sign in with another
provider. See our Privacy Policy and
Terms.
Kin Score
How this is scored →