CircleCI

Freemium

circleci.com

High-performance continuous integration and delivery platform automating software testing, container packaging, and production deployments.

About CircleCI

CircleCI is an industry-leading continuous integration and continuous delivery (CI/CD) automation platform engineered to accelerate software release velocity. Operating across modern cloud and self-hosted environments, CircleCI automatically pulls code commits, executes comprehensive test suites, builds container images, and releases applications to production with minimal developer intervention.

The platform integrates advanced machine learning models through features like test splitting and intelligent test runner capabilities, which analyze historical test run durations and distribute test cases evenly across concurrent execution nodes. CircleCI Orbs provide reusable configuration packages that simplify connecting builds with hundreds of third-party cloud services, security scanners, and monitoring systems.

CircleCI is accessible via a web interface and integrated command-line tool, supporting Docker execution, Linux, macOS, and Windows virtual machines. It provides a generous free tier with thousands of build credits per month alongside scalable paid tiers tailored for fast-growing engineering teams.

Key Features

Core capabilities and technical highlights of CircleCI

Intelligent test splitting and predictive runner capabilities that balance workloads based on historical execution metrics.

Pre-configured CircleCI Orbs ecosystem providing thousands of certified integrations for popular developer tools.

Cross-platform execution environments spanning Docker containers, Linux machines, macOS executors, and Windows runners.

Granular caching mechanisms for dependencies and build artifacts to maximize pipeline execution speeds.

Popular Use Cases

How teams, developers, and creators get value from CircleCI

1Automate comprehensive unit and integration testing workflows on every pull request to verify code quality.

2Build, tag, and publish Docker container images directly to cloud registries upon successful pipeline completion.

3Deploy web applications to serverless runtimes and Kubernetes clusters using parameterized deployment scripts.

4Parallelize sprawling test suites across dozens of concurrent containers to reduce build times from hours to minutes.

Frequently Asked Questions

Common questions and answers regarding CircleCI

Does CircleCI offer a free tier?

Yes, CircleCI provides a free tier with 6,000 build credits per month, unlimited users, and access to Docker and Linux execution environments.

What are CircleCI Orbs?

Orbs are open-source, shareable packages of configuration logic that make it easy to integrate testing, security scanning, and deployment tools into pipelines.

Can CircleCI build iOS and macOS applications?

Yes, CircleCI provides dedicated macOS virtual machines optimized for compiling Xcode projects and packaging iOS apps.

How does CircleCI decrease pipeline execution time?

CircleCI leverages intelligent test splitting, dependency caching, and massive concurrency to parallelize testing across multiple containers.

Does CircleCI support self-hosted runners?

Yes, teams can connect self-hosted runners to CircleCI Cloud to run jobs behind private firewalls or on specialized hardware.