I solved it.
For future readers, you would be better off with using GitLab’s excellent Package Registry for deploying packages. This is my final CI YML file for your reference.
stages:
- build
- upload
- release
variables:
PACKAGE_REGISTRY_URL: "${CI_API_V4_URL}/projects/${CI_PROJECT_ID}/packages/generic/quack/${CI_COMMIT_TAG}"
build:
stage: build
image: rust:latest
script:
- cargo build --release
- mkdir bin
- mv target/release/quack bin/quack-${CI_COMMIT_TAG}
cache:
paths:
- target/release/
artifacts:
paths:
- bin
rules:
- if: $CI_COMMIT_TAG
upload:
stage: upload
image: curlimages/curl:latest
rules:
- if: $CI_COMMIT_TAG
script:
- 'curl --header "JOB-TOKEN: ${CI_JOB_TOKEN}" --upload-file bin/quack-${CI_COMMIT_TAG} ${PACKAGE_REGISTRY_URL}/quack-${CI_COMMIT_TAG}'
release:
stage: release
image: registry.gitlab.com/gitlab-org/release-cli:latest
rules:
- if: $CI_COMMIT_TAG
script:
- 'release-cli create --name "quack-$CI_COMMIT_TAG" --tag-name $CI_COMMIT_TAG --assets-link "{\"name\":\"quack-${CI_COMMIT_TAG}\", \"url\":\"${PACKAGE_REGISTRY_URL}/quack-${CI_COMMIT_TAG}\"}"'