Rebar3 provider for building OCI container images from releases.

Usage

rebar3 release
rebar3 ocibuild -t myapp:1.0.0

Or push directly to a registry:

rebar3 ocibuild -t myapp:1.0.0 --push ghcr.io/myorg

Options

• -t, --tag - Image tag (e.g., myapp:1.0.0). Can be specified multiple times.
• -o, --output - Output tarball path (default: <tag>.tar.gz)
• -p, --push - Push to registry (e.g., ghcr.io/myorg)
• -a, --annotation - Add manifest annotation KEY=VALUE (repeatable)
• --base - Override base image
• --release - Release name (if multiple configured)
• --compression - Layer compression: gzip, zstd, or auto (default: auto)

Configuration

Add to your rebar.config:

{ocibuild, [
    {base_image, "debian:stable-slim"},
    {workdir, "/app"},
    {env, #{~"LANG" => ~"C.UTF-8"}},
    {expose, [8080]},
    {labels, #{}},
    {annotations, #{<<"org.opencontainers.image.description">> => <<"My awesome application">>}},
    {tag, ["myapp:1.0.0", "myapp:latest"]},  % or a single string: "myapp:1.0.0"
    {compression, auto}  % gzip, zstd, or auto (zstd on OTP 28+, gzip on OTP 27)
]}.

Authentication

Set environment variables for registry authentication:

For pushing to registry:

export OCIBUILD_PUSH_USERNAME="user"
export OCIBUILD_PUSH_PASSWORD="pass"

For pulling private base images (optional, anonymous pull used if unset):

export OCIBUILD_PULL_USERNAME="user"
export OCIBUILD_PULL_PASSWORD="pass"