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---
stage: Verify
group: Continuous Integration
info: To determine the technical writer assigned to the Stage/Group associated with this page, see https://about.gitlab.com/handbook/engineering/ux/technical-writing/#assignments
type: reference
---
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# Get started with GitLab CI/CD **(FREE)**
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Use this document to get started with
GitLab [continuous integration ](https://about.gitlab.com/stages-devops-lifecycle/continuous-integration/ ).
Before you start, make sure you have:
- A project in GitLab that you would like to use CI/CD for.
- Maintainer or owner access for the project.
If you are migrating from another CI/CD tool, view this documentation:
- [Migrate from CircleCI ](../migration/circleci.md ).
- [Migrate from Jenkins ](../migration/jenkins.md ).
## CI/CD process overview
To use GitLab CI/CD:
1. [Ensure you have runners available ](#ensure-you-have-runners-available ) to run your jobs.
If you don't have a runner, [install GitLab Runner ](https://docs.gitlab.com/runner/install/ )
and [register a runner ](https://docs.gitlab.com/runner/register/ ) for your instance, project, or group.
1. [Create a `.gitlab-ci.yml` file ](#create-a-gitlab-ciyml-file )
at the root of your repository. This file is where you define your CI/CD jobs.
When you commit the file to your repository, the runner runs your jobs.
The job results [are displayed in a pipeline ](#view-the-status-of-your-pipeline-and-jobs ).
### Ensure you have runners available
In GitLab, runners are agents that run your CI/CD jobs.
You might already have runners available for your project, including
[shared runners ](../runners/README.md#shared-runners ), which are
available to all projects in your GitLab instance.
To view available runners:
- Go to **Settings > CI/CD** and expand **Runners** .
As long as you have at least one runner that's active, with a green circle next to it,
you have a runner available to process your jobs.
If no runners are listed on the **Runners** page in the UI, you or an administrator
must [install GitLab Runner ](https://docs.gitlab.com/runner/install/ ) and
[register ](https://docs.gitlab.com/runner/register/ ) at least one runner.
If you are testing CI/CD, you can install GitLab Runner and register runners on your local machine.
When your CI/CD jobs run, they run on your local machine.
### Create a `.gitlab-ci.yml` file
The `.gitlab-ci.yml` file is a [YAML ](https://en.wikipedia.org/wiki/YAML ) file where
you configure specific instructions for GitLab CI/CD.
In this file, you define:
- The structure and order of jobs that the runner should execute.
- The decisions the runner should make when specific conditions are encountered.
For example, you might want to run a suite of tests when you commit to
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any branch except the default branch. When you commit to the default branch, you want
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to run the same suite, but also publish your application.
All of this is defined in the `.gitlab-ci.yml` file.
To create a `.gitlab-ci.yml` file:
1. Go to **Project overview > Details** .
1. Above the file list, select the branch you want to commit to,
click the plus icon, then select **New file** :
![New file ](img/new_file_v13_6.png )
1. For the **Filename** , type `.gitlab-ci.yml` and in the larger window,
paste this sample code:
```yaml
build-job:
stage: build
script:
- echo "Hello, $GITLAB_USER_LOGIN!"
test-job1:
stage: test
script:
- echo "This job tests something"
test-job2:
stage: test
script:
- echo "This job tests something, but takes more time than test-job1."
- echo "After the echo commands complete, it runs the sleep command for 20 seconds"
- echo "which simulates a test that runs 20 seconds longer than test-job1"
- sleep 20
deploy-prod:
stage: deploy
script:
- echo "This job deploys something from the $CI_COMMIT_BRANCH branch."
```
`$GITLAB_USER_LOGIN` and `$CI_COMMIT_BRANCH` are
[predefined variables ](../variables/predefined_variables.md )
that populate when the job runs.
1. Click **Commit changes** .
The pipeline starts when the commit is committed.
#### `.gitlab-ci.yml` tips
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- If you want the runner to [use a Docker container to run the jobs ](../docker/using_docker_images.md ),
edit the `.gitlab-ci.yml` file
to include an image name:
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```yaml
default:
image: ruby:2.7.2
```
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This command tells the runner to use a Ruby image from Docker Hub
and to run the jobs in a container that's generated from the image.
This process is different than
[building an application as a Docker container ](../docker/using_docker_build.md ).
Your application does not need to be built as a Docker container to
run CI/CD jobs in Docker containers.
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- To validate your `.gitlab-ci.yml` file, use the
[CI Lint tool ](../lint.md ), which is available in every project.
- You can also use [CI/CD configuration visualization ](../pipeline_editor/index.md#visualize-ci-configuration ) to
view a graphical representation of your `.gitlab-ci.yml` file.
- For the complete `.gitlab-ci.yml` syntax, see
[the `.gitlab-ci.yml` reference topic ](../yaml/README.md ).
### View the status of your pipeline and jobs
When you committed your changes, a pipeline started.
To view your pipeline:
- Go **CI/CD > Pipelines** .
A pipeline with three stages should be displayed:
![Three stages ](img/three_stages_v13_6.png )
- To view a visual representation of your pipeline, click the pipeline ID.
![Pipeline graph ](img/pipeline_graph_v13_6.png )
- To view details of a job, click the job name, for example, `deploy-prod` .
![Job details ](img/job_details_v13_6.png )
If the job status is `stuck` , check to ensure a runner is probably configured for the project.