No buildpack group passed detection

[cmdjulian]

When I try to use the build pack with:

pack build test-image:latest \
  --path build/libs/test.jar \
  --env BP_JVM_VERSION="11.*" \
  --env JAVA_TOOL_OPTIONS=-XX:+DisableAttachMechanism \
  --builder paketobuildpacks/builder:base \
  --buildpack paketo-buildpacks/eclipse-openj9 \
  --buildpack paketo-buildpacks/java \
  --buildpack fagiani/apt

it errors out with:

base: Pulling from paketobuildpacks/builder
Digest: sha256:4797e9561534e3b628da62201555a3090db077266314e6fa175c2d9187f8429d
Status: Image is up to date for paketobuildpacks/builder:base
base-cnb: Pulling from paketobuildpacks/run
Digest: sha256:781ccd109ecd2b800422697313035a2c37378ff26b6fa97d5205566197bcbb79
Status: Image is up to date for paketobuildpacks/run:base-cnb
gcr.io/paketo-buildpacks/eclipse-openj9@sha256:3583830bf398152f982cc3498f7086dc7dede9d62450a2fd08e506dd75a00883: Pulling from paketo-buildpacks/eclipse-openj9
Digest: sha256:3583830bf398152f982cc3498f7086dc7dede9d62450a2fd08e506dd75a00883
Status: Image is up to date for gcr.io/paketo-buildpacks/eclipse-openj9@sha256:3583830bf398152f982cc3498f7086dc7dede9d62450a2fd08e506dd75a00883
ghcr.io/fagiani/buildpacks/fagiani_apt@sha256:18de385c95c3f5111a46e7abbadb5354f84022b0b3efd85d8bf72c696e48d577: Pulling from fagiani/buildpacks/fagiani_apt
Digest: sha256:18de385c95c3f5111a46e7abbadb5354f84022b0b3efd85d8bf72c696e48d577
Status: Image is up to date for ghcr.io/fagiani/buildpacks/fagiani_apt@sha256:18de385c95c3f5111a46e7abbadb5354f84022b0b3efd85d8bf72c696e48d577
===> DETECTING
======== Output: fagiani/apt@0.2.1 ========
no
err:  fagiani/apt@0.2.1 (1)
ERROR: No buildpack groups passed detection.
ERROR: failed to detect: buildpack(s) failed with err
ERROR: failed to build: executing lifecycle: failed with status code: 21

Can you provide me with some clues how to fix it?

[fagiani]

Hello @cmdjulian !

Have you created the Aptfile as mentioned on the README?

If so, could you please share its contents here?

Thanks for using the buildpack!