Runner
ELI5 — The Vibe Check
A runner is the actual computer that does the work when your pipeline runs. When you push code and CI kicks in, a runner is the machine that wakes up, checks out your code, runs your tests, and reports back. It's like the worker on the assembly line — the pipeline is the blueprint, the runner does the physical work.
Real Talk
A runner is an agent (a server or container) that executes the jobs in a CI/CD pipeline. GitHub calls them GitHub-hosted or self-hosted runners. GitLab has GitLab Runners. They can be shared infrastructure provided by the platform, or your own machines registered to process jobs.
Show Me The Code
jobs:
build:
runs-on: ubuntu-latest # This picks the runner
steps:
- run: echo "Running on a GitHub-hosted runner"
When You'll Hear This
"The job is queued waiting for a runner." / "Set up a self-hosted runner for faster build times."
Related Terms
CI (Continuous Integration)
CI is like a robot assistant that instantly checks your homework every time you hand it in.
GitHub Actions
GitHub Actions is CI/CD built right into GitHub. Push code, run tests, deploy — all from YAML files in your repo. No separate CI server needed.
Job
A job is one chunk of work in your pipeline, running on its own machine.
Pipeline
A pipeline is like an assembly line at a factory.
Workflow
A workflow is a recipe for your robot assistant — it tells CI exactly what to do when something happens. 'When someone pushes code, run tests.