CI/CD expressions

CI/CD expressions enable dynamic configuration in your CI/CD pipelines by referencing variables and inputs in specialized contexts. GitLab evaluates expressions in the pipeline configuration before the pipeline is created.

Configuration expressions

Configuration expressions use the $[[ ]] syntax and are evaluated at pipeline creation time (compile-time). They enable dynamic configuration based on different contexts.

All configuration expressions share these characteristics:

• Compile-time evaluation: Values are resolved when the pipeline configuration is created, not during job execution. A large number of expressions can increase pipeline creation time, but does not affect job execution time.
• Static resolution: Cannot perform dynamic logic or access runtime job state.

Configuration expressions support different contexts for accessing values:

Inputs context

Use the inputs. context to reference CI/CD inputs in reusable configurations using $[[ inputs.INPUT_NAME ]] syntax.

For example:

spec:
  inputs:
    environment:
      default: production
    job-stage:
      default: test
---
scan-website:
  stage: $[[ inputs.job-stage ]]
  script: ./scan-website $[[ inputs.environment ]]

input. expressions have the following characteristics:

• Type validation: Supports string, number, boolean, and array types with validation. Input validation prevents pipeline creation with invalid values.
• Function support: Predefined functions like expand_vars and truncate can manipulate values.
• Scope: Available in the file where defined, or passed explicitly with include:inputs.

Matrix context

Use the matrix. context to reference parallel:matrix values by using a $[[ matrix.IDENTIFIER ]] syntax. Use it in job dependencies to enable dynamic 1:1 mappings between parallel:matrix jobs.

For example:

.os-arch-matrix:
  parallel:
    matrix:
      - OS: [ubuntu, alpine]
        ARCH: [amd64, arm64]

build:
  script: echo "Testing $OS on $ARCH"
  parallel: !reference [.os-arch-matrix, parallel]

test:
  script: echo "Testing $OS on $ARCH"
  parallel: !reference [.os-arch-matrix, parallel]
  needs:
    - job: build
      parallel:
        matrix:
          - OS: ['$[[ matrix.OS ]]']
            ARCH: ['$[[ matrix.ARCH ]]']

matrix. expressions have the following characteristics:

• Scoped to job-level parallel:matrix: Only values from the current job can be referenced.
• Automatic mapping: Creates 1:1 dependencies between matrix jobs across stages

Component context

Use the component. context to reference CI/CD component metadata in component templates using $[[ component.FIELD_NAME ]] syntax.

Component context provides metadata about the component itself, such as its name, version, and the commit SHA. This allows component templates to reference their own metadata dynamically.

To use component context, declare which fields are needed in the spec:component header, then reference them in the component template.

For example:

spec:
  component: [name, version]
  inputs:
    image_tag:
      default: latest
---

build-job:
  image: registry.example.com/$[[ component.name ]]:$[[ component.version ]]
  script:
    - echo "Building with component version $[[ component.version ]]"

Related topics

• CI/CD inputs
• CI/CD components
• Matrix expressions
• YAML optimization