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Using Containers

1 month ago1 min read
On This Page
  • Overview
  • Migrating to a usage-based plan

You can read about usage-based plans in detail in this document.


Every change committed to your version control system triggers CircleCI to checkout your code and run your job workflow inside a fresh, on-demand, isolated container or virtual machine with access to the following, depending on your plan:

  • Concurrency - Utilizing multiple containers to run multiple jobs at the same time. To take advantage of concurrency, configure your development workflow using the Orchestrating Workflows document and run your jobs in parallel as shown in the Sample Config Files document.

  • Parallelism - Splitting tests across multiple containers, allowing you to dramatically speed up your test suite. Update your .circleci/config.yml file to run your tests in parallel as described in the Configuring CircleCI document. Learn how to update your config file to parallelize and split tests to decrease your build time by reading the Running Tests in Parallel documentation.

Migrating to a usage-based plan

Refer to this Discuss posts for step-by-step instructions to migrate your plan, or contact customer support.

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