Bootstrap a GitLab CI pipeline that runs in a Kubernetes executor with per-job ephemeral namespaces and pod resource limits

Steps

1. Install GitLab Runner with the Kubernetes executor via Helm: helm repo add gitlab https://charts.gitlab.io && helm install gitlab-runner gitlab/gitlab-runner --set gitlabUrl=https://gitlab.com --set runnerToken=<TOKEN> --namespace gitlab-runner
2. Configure config.toml (via Helm values runners.config) to set [runners.kubernetes] with namespace, image, cpu_request, cpu_limit, memory_request, memory_limit for the build container
3. Set namespace_per_job = true (or per_job_namespace_labels) in the runner config so each CI job receives an isolated Kubernetes namespace, enabling resource cleanup via namespace deletion
4. In .gitlab-ci.yml set resource_group: <env> on deploy jobs to serialize concurrent deployments to the same environment without manual locking
5. Define image: and services: at the job level to override the default executor image; the Kubernetes executor launches services as additional containers in the same pod
6. Use variables: KUBERNETES_CPU_REQUEST, KUBERNETES_MEMORY_LIMIT etc. at the job or pipeline level to override executor resource settings per job without changing runner config