This guide is most relevant to buildpack authors.
See the spec release for buildpack API 0.8 for the full list of changes and further details.
Buildpacks may specify the working directory for a process by setting the
working-dir field on the process in
Prior to this, all processes ran from the app directory (
Running a process from a different directory typically involved running a shell to execute a
cd command and then start the process, like:
[[processes]] command = "bash" args = ["-c", "cd <working-dir> && <start-process>"]
Buildpacks can now specify the process directly with a specific working directory, like:
[[processes]] command = "<start-process>" working-dir = "<working-dir>"
For details, see RFC 81.
The positional arguments to the
build executables are deprecated.
Lifecycle now accepts these values as environment variables.
To upgrade, buildpack authors should use the following environment variables:
CNB_PLATFORM_DIRreplaces the first positional argument.
CNB_BUILD_PLAN_PATHreplaces the second positional argument.
CNB_LAYERS_DIRreplaces the first positional argument.
CNB_PLATFORM_DIRreplaces the second positional argument.
CNB_BP_PLAN_PATHreplaces the third positional argument.
For details, see RFC 100.