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Fetch the complete documentation index at: https://docs.blaxel.ai/llms.txt

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You can build a job image once and reuse it across multiple job definitions (e.g. different memory / disk / region profiles) without rebuilding. The workflow is:
  1. Build and push the image through a single “dev” job.
  2. Reference the resulting image digest from as many Job manifests as you need.
  3. Roll out changes to production runners by re-applying the manifests.
This is particularly useful when images are large: a full rollout across every host can take up to 20 minutes, so sharing one image across many jobs is much cheaper than rebuilding per job.

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1. Build the image via a dev job

Create a blaxel.toml describing the dev job used to build and host the image: 
type = "job"
name = "github-runner-dev"

[runtime]
diskPercent = 50
memory = 4096
timeout = 3600
maxRetries = 0
Deploy it with: 
bl deploy
Alternatively, use the command below to push the image without deploying it: 
bl push
Once deployed, obtain the image reference: 
bl get job github-runner-dev -o json | jq -r '.[].spec.runtime.image'
# -> job/github-runner-dev:jv7lsvdihfqz

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2. Create one manifest per runner profile

For every runner variant you need (size, region, timeout, …), write a small Job manifest that points at the image produced above. 
# 4grunner.yaml
apiVersion: blaxel.ai/v1alpha1
kind: Job
metadata:
  name: github-runner-4g
spec:
  region: us-was-1
  runtime:
    diskPercent: 50
    image: job/github-runner-dev:<your-image-digest>  # from: bl get job github-runner-dev -o json | jq -r '.[].spec.runtime.image'
    memory: 4096
    timeout: 3600
Apply it: 
bl apply -f 4grunner.yaml
You can bootstrap a new manifest from the dev job’s current spec: 
bl get job github-runner-dev -o yaml

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3. Create additional jobs from the shared image

You can now use the same image to deploy jobs with different manifests/runner profiles, depending on your requirements. Because the image is shared, hosts only pull it once instead of once per job. To update the image, you can build a new image on github-runner-dev, validate it there, then promote it to production by bumping the image: field in each manifest and re-applying.
Last modified on May 6, 2026