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In this guide, you’ll learn how to leverage GitHub Actions’ matrix strategy to run the same job across multiple environments without duplicating YAML. By the end, you’ll be able to execute Docker commands on various OS runners and image combinations in parallel.

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A straightforward workflow

Below is a basic workflow that defines two separate jobs—one on Ubuntu and one on Windows—to echo Docker details and run the hello-world image. 
name: Matrix Configuration

on:
  push:
  workflow_dispatch:

jobs:
  deploy-on-ubuntu:
    runs-on: ubuntu-latest
    steps:
      - name: Echo Docker Details
        run: docker info
      - name: Run Image
        run: docker run hello-world

  deploy-on-windows:
    runs-on: windows-latest
    steps:
      - name: Echo Docker Details
        run: docker info
      - name: Run Image
        run: docker run hello-world
This triggers on both push and manual dispatch, executing the same two steps on different OS runners.
The image shows a GitHub Actions page displaying a list of workflow runs, including their status, branch, and execution time. The interface is dark-themed, with options for managing workflows on the left sidebar.
Both jobs kick off in parallel and complete successfully.

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Inspecting the Windows job

Click into deploy-on-windows to view details about the runner, Docker info, and the hello-world output: 
Run docker info
Client:
 Version: 24.0.6
 Context: default
 Debug Mode: false
 Plugins:
  compose: Docker Compose (Docker Inc.)
    Version: v2.22.0
    Path: C:\ProgramData\Docker\cli-plugins\docker-compose.exe

Server:
 Containers: 0
  Running: 0
  Paused: 0
  Stopped: 0
 Images: 5
 Server Version: 24.0.6
 Storage Driver: windowsfilter
 Logging Driver: json-file
Then it pulls and runs hello-world: 
Run docker run hello-world
Unable to find image 'hello-world:latest' locally
latest: Pulling from library/hello-world
...
Hello from Docker!
This message shows that your installation appears to be working correctly.
The image shows a GitHub Actions interface with a job titled "deploy-on-windows" that has successfully completed. It details the setup process, including the operating system and runner version used.

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The problem of repetition

Imagine scaling this to more OS versions or Docker images. You’d end up copying and pasting nearly identical job definitions: 
jobs:
  deploy-on-ubuntu:
    runs-on: ubuntu-latest
    steps:
      - name: Echo Docker Details
        run: docker info
      - name: Run Image
        run: docker run hello-world

  deploy-on-windows:
    runs-on: windows-latest
    steps:
      - name: Echo Docker Details
        run: docker info
      - name: Run Image
        run: docker run hello-world

  # ...more duplicates for other OS or images
Maintaining this becomes a headache as you add environments.

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Introducing the matrix strategy

GitHub Actions’ matrix lets you define multiple variables, and it automatically expands one job into many. Here’s the minimal syntax: 
jobs:
  example_matrix:
    strategy:
      matrix:
        version: [10, 12, 14]
        os: [ubuntu-latest, windows-latest]
This generates six parallel jobs (3 versions × 2 OS).
FieldDescriptionExample
strategy.matrixDefines variables to expandversion: [10,12,14], os: [ubuntu,windows]
runs-onRunner label substituted by matrixruns-on: ${{ matrix.os }}
stepsStandard job stepsrun: docker run ${{ matrix.image }}
Learn more in the GitHub Actions matrix documentation.
The image shows a GitHub Actions interface with a workflow run summary for a matrix job, displaying details of a successful deployment on Ubuntu.

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Converting our workflow to use a matrix

Let’s refactor our example to run two Docker images (hello-world and alpine) across three OS environments (ubuntu-latest, ubuntu-20.04, windows-latest): 
name: Matrix Configuration

on:
  push:
  workflow_dispatch:

jobs:
  deploy:
    strategy:
      matrix:
        os: [ubuntu-latest, ubuntu-20.04, windows-latest]
        image: [hello-world, alpine]
    runs-on: ${{ matrix.os }}
    steps:
      - name: Echo Docker Details
        run: docker info

      - name: Run ${{ matrix.image }} on ${{ matrix.os }}
        run: docker run ${{ matrix.image }}
  • runs-on: ${{ matrix.os }} selects the runner OS dynamically.
  • The second step pulls and runs each image on each OS.
When you push this change, GitHub Actions spawns six jobs in parallel:
The image shows a GitHub Actions workflow interface with a matrix configuration, displaying the status of various deployment jobs for different environments like Ubuntu and Windows.
You can also filter specific combinations using include and exclude under strategy.matrix. For example:
strategy:
  matrix:
    os: [ubuntu-latest, windows-latest]
    image: [hello-world, alpine]
    exclude:
      - os: windows-latest
        image: alpine
This skips running Alpine on Windows.

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Handling failures

In some cases, certain image/OS combinations may not be supported. For example, alpine has no Windows manifest, so that job fails:
The image shows a GitHub Actions workflow summary with a matrix configuration. It indicates a failure in the deployment process, with some jobs succeeding and others failing.
Run docker run alpine
Unable to find image 'alpine:latest' locally
latest: Pulling from library/alpine
docker: no matching manifest for windows/amd64 in the manifest list entries.
See 'docker run --help'.
Error: Process completed with exit code 1
By default, a failure in one matrix job cancels the rest and marks the workflow as failed. Use continue-on-error: true on a step or job-level conditionals if you want to proceed despite errors.

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