Build Matrix

A build matrix is made up by several multiple jobs that run in parallel.

This can be useful in many cases, but the two primary reasons to use a build matrix are:

The examples on this page focus on the latter use case.

There are two ways to define a matrix in the .travis.yml file:

  • Using the Matrix Expansion feature
  • Listing individual job configs

Both features can be combined.

Matrix Expansion #

Certain keys are defined as matrix expansion keys that take arrays of values, creating an additional job per value. If several matrix expansion keys are given, this multiplies the number of jobs created.

For example, the following configuration produces a build matrix that expands to 8 individual (2 * 2 * 2) jobs, combining each value from the three matrix expansion keys rvm, gemfile, and env.

rvm:
- 2.5
- 2.2
gemfile:
- gemfiles/Gemfile.rails-3.2.x
- gemfiles/Gemfile.rails-3.0.x
env:
- ISOLATED=true
- ISOLATED=false

Listing individual jobs #

In addition, jobs can be specified by adding entries to the key jobs.include.

For example, if not all of those combinations of the matrix expansion above are relevant, jobs can be specified individually like so:

jobs:
  include:
  - rvm: 2.5
    gemfile: gemfiles/Gemfile.rails-3.2.x
    env: ISOLATED=false
  - rvm: 2.2
    gemfile: gemfiles/Gemfile.rails-3.0.x
    env: ISOLATED=true

Build matrixes are currently limited to a maximum of 200 jobs for both private and public repositories. If you are on an open-source plan, please remember that Travis CI provides this service free of charge to the community. So please only specify the matrix you actually need.

You can also have a look at the Language section in our Travis CI Build Config Reference.

Excluding Jobs #

The build matrix expansion sometimes produced unwanted combinations. In that case it can be convenient to exclude certain combinations using the key jobs.exclude, instead of listing all jobs individually.

For example, this would exclude two jobs from the build matrix:

jobs:
  exclude:
  - rvm: 1.9.3
    gemfile: gemfiles/Gemfile.rails-2.3.x
    env: ISOLATED=true
  - rvm: jruby
    gemfile: gemfiles/Gemfile.rails-2.3.x
    env: ISOLATED=true

If the jobs you want to exclude from the build matrix share the same matrix parameters, you can specify only those and omit the varying parts.

Suppose you have:

language: ruby
rvm:
- 1.9.3
- 2.0.0
- 2.1.0
env:
- DB=mongodb
- DB=redis
- DB=mysql
gemfile:
- Gemfile
- gemfiles/rails4.gemfile
- gemfiles/rails31.gemfile
- gemfiles/rails32.gemfile

This results in a 3×3×4 build matrix. To exclude all jobs which have rvm value 2.0.0 and gemfile value Gemfile, you can write:

jobs:
  exclude:
  - rvm: 2.0.0
    gemfile: Gemfile

Which is equivalent to:

jobs:
  exclude:
  - rvm: 2.0.0
    gemfile: Gemfile
    env: DB=mongodb
  - rvm: 2.0.0
    gemfile: Gemfile
    env: DB=redis
  - rvm: 2.0.0
    gemfile: Gemfile
    env: DB=mysql

Excluding jobs with env value #

When excluding jobs with env values, the value must match exactly.

For example,

language: ruby
rvm:
- 1.9.3
- 2.0.0
- 2.1.0
env:
- DB=mongodb SUITE=all
- DB=mongodb SUITE=compact
- DB=redis
- DB=mysql
jobs:
  exclude:
    - rvm: 1.9.3
      env: DB=mongodb

defines a 3×4 matrix, because the env value does not match with any job defined in the matrix.

To exclude all Ruby 1.9.3 jobs with DB=mongodb set, write:

language: ruby
rvm:
- 1.9.3
- 2.0.0
- 2.1.0
env:
- DB=mongodb SUITE=all
- DB=mongodb SUITE=compact
- DB=redis
- DB=mysql
jobs:
  exclude:
    - rvm: 1.9.3
      env: DB=mongodb SUITE=all # not 'env: DB=mongodb' or 'env: SUITE=all DB=mongodb'
    - rvm: 1.9.3
      env: DB=mongodb SUITE=compact # not 'env: SUITE=compact DB=mongodb'

Explicitly Including Jobs #

It is also possible to include entries into the matrix with jobs.include:

jobs:
  include:
  - rvm: ruby-head
    gemfile: gemfiles/Gemfile.rails-3.2.x
    env: ISOLATED=false

This adds a particular job to the build matrix which has already been populated.

This is useful if you want to only test the latest version of a dependency together with the latest version of the runtime.

You can use this method to create a build matrix containing only specific combinations. For example,

language: python
jobs:
  include:
  - python: "2.7"
    env: TEST_SUITE=suite_2_7
  - python: "3.8"
    env: TEST_SUITE=suite_3_8
  - python: "pypy"
    env: TEST_SUITE=suite_pypy
script: ./test.py $TEST_SUITE

creates a build matrix with 3 jobs, which runs test suite for each version of Python.

Explicitly included jobs inherit the first value in the array #

The jobs which are explicitly included inherit the first value of the expansion keys defined.

In this example with a 3-job Python build matrix, each job in jobs.include has the python value set to '3.8'. You can explicitly set the python version for a specific entry:

language: python
python:
  - '3.8'
  - '3.7'
  - '2.7'
jobs:
  include:
    - python: '3.8' # this is not strictly necessary
      env: EXTRA_TESTS=true
    - python: '3.7'
      env: EXTRA_TESTS=true
script: env $EXTRA_TESTS ./test.py $TEST_SUITE

Explicitly included jobs with only one element in the build matrix #

As a special case, if your build matrix has only one element and you have explicitly included jobs, matrix expansion is not done and the explicit jobs completely define your build. For example:

language: python
python:
  - '3.8'
jobs:
  include:
    - env: EXTRA_TESTS=true
# only defines one job with `python: 3.8` and `env: EXTRA_TESTS=true`

If you need a (sole) job from the matrix in such case, add a blank job entry with curly brackets to the build instruction (as that instruction would inherit all values from the matrix):

language: python
python:
  - '3.8'
jobs:
  include:
    - {}
    - env: EXTRA_TESTS=true
# defines two jobs:
#   - python: 3.8
#   - python: 3.8
#     env: EXTRA_TESTS=true

Rows that are Allowed to Fail #

You can define rows that are allowed to fail in the build matrix. Allowed failures are items in your build matrix that are allowed to fail without causing the entire build to fail. This lets you add in experimental and preparatory builds to test against versions or configurations that you are not ready to officially support.

Define allowed failures in the build matrix as key/value pairs:

jobs:
  allow_failures:
  - rvm: 1.9.3

Matching Jobs with allow_failures #

When matching jobs against the definitions given in allow_failures, all conditions in allow_failures must be met exactly, and all the keys in allow_failures element must exist in the top level of the build matrix (i.e., not in jobs.include).

allow_failures Examples #

Consider

language: ruby

rvm:
- 2.0.0
- 2.1.6

env:
  global:
  - SECRET_VAR1=SECRET1
  jobs:
  - SECRET_VAR2=SECRET2

jobs:
  allow_failures:
    - env: SECRET_VAR1=SECRET1 SECRET_VAR2=SECRET2

Here, no job is allowed to fail because no job has the env value SECRET_VAR1=SECRET1 SECRET_VAR2=SECRET2.

Next,

language: php
php:
- 5.6
- 7.0
jobs:
  include:
  - php: 7.0
    env: KEY=VALUE
  allow_failures:
  - php: 7.0
    env: KEY=VALUE

Without the top-level env, no job will be allowed to fail.

Fast Finishing #

If some rows in the build matrix are allowed to fail, the build won’t be marked as finished until they have completed.

To mark the build as finished as soon as possible, add fast_finish: true to the jobs section of your .travis.yml like this:

jobs:
  fast_finish: true

Now, the build result will be determined as soon as all the required jobs finish, based on these results, while the rest of the allow_failures jobs continue to run.

Using Different Programming Languages per Job #

You can also use the jobs.include feature to have different languages for each job in your build. For example,

dist: xenial
language: php
php:
  - '5.6'

jobs:
  include:
    - language: python
      python: 3.8
      script:
      - python -c "print('Hi from Python!')"

    - language: node_js
      node_js: 12
      script:
      - node -e "console.log('Hi from NodeJS!')"

    - language: java
      jdk: openjdk8
      script:
      - javac -help

This creates a build with 3 jobs as follows:

  • A Python 3.8 job
  • A Node.js 12 job
  • A Java OpenJDK 8 job

Job Names #

Jobs listed in jobs.include can be named by using the key name, like so:

jobs:
  include:
  - name: Job 1
    script: echo "Running job 1"

This name will appear on the build matrix UI and can be convenient in order to quickly identify jobs in a large matrix.

Jobs generated through the Matrix Expansion feature cannot be named.

Job Uniqueness and Duplicate Jobs #

Jobs need to be unique, and duplicate jobs are dropped during the Build Config Validation process.

For example, this config would result in only one job using the YAML anchors and aliases:

_shared_job: &shared_job
  script: echo "shared script config"
jobs:
  include:
  - <<: *shared_job
  - <<: *shared_job

In rare circumstances it can still be desirable to execute multiple jobs with the same config. In such cases, job uniqueness can be achieved by specifying any additional key, e.g. a job name:

_shared_job: &shared_job
  script: echo "shared script config"
jobs:
  include:
  - name: Job 1
    <<: *shared_job
  - name: Job 2
    <<: *shared_job