Runner Pool

ImpVMRunnerPool manages ImpVM instances for CI/CD jobs. It currently supports GitHub Actions self-hosted runners.

Sections

• Under the Hood — source-backed runner path, implemented lifecycle, and live-evidence boundary
• Scaling
• E2E Runbook
• 20-Minute Technical Presentation

How it Works

The pool controller creates and removes ImpVM objects to match runner demand. Each VM receives one JIT registration setup, then runs as an ephemeral GitHub Actions self-hosted runner. The controller removes terminal VMs and reconciles replacement capacity.

GitHub Actions Visibility

GitHub only sees capacity after runners register. The pool keeps minIdle pre-registered runners available for fast job pickup. Monitor both the Kubernetes side (pool status, ImpVM count) and the GitHub side (runner inventory).

Minimal Example

apiVersion: imp.dev/v1alpha1
kind: ImpVMClass
metadata:
  name: runner-class
  namespace: default
spec:
  vcpu: 2
  memoryMiB: 2048
  diskGiB: 10
---
apiVersion: imp.dev/v1alpha1
kind: ImpVMTemplate
metadata:
  name: gh-runner
  namespace: default
spec:
  classRef:
    name: runner-class
  image: ghcr.io/syscode-labs/imp-runner:latest
---
apiVersion: imp.dev/v1alpha1
kind: ImpVMRunnerPool
metadata:
  name: ci-pool
  namespace: default
spec:
  templateName: gh-runner
  platform:
    type: github-actions
    credentialsSecret: github-runner-app
    tokenSource: github_app
    scope:
      org: my-org
    runnerGroup: imp-runners
  scaling:
    mode: polling
    minIdle: 1
    maxConcurrent: 5
    scaleUpStep: 1
    cooldownSeconds: 30
    polling:
      enabled: true
      intervalSeconds: 30

Create the github-runner-app Secret before applying this pool. The E2E runbook shows its required fields.