Bitbucket Pipelines vs Circle CI comparison of Continuous Integration servers
What are the differences between Bitbucket Pipelines and Circle CI?

Best Jira integration possible

Premium Support

SaaS / On Premise

SaaS, Self-hosted / On Premise

Yes

Offers a very modest free cloud plan, limited to 5 users, 50 minutes of build time per month and 1GB storage. There's no free self-hosted version, but they do offer a $10 one-time payment plan for 10 users (build time and storage is only limited by your infrastructure)

Yes

Provides a free plan for it's SaaS solution, for up to 1000 build minutes per month, 1 container and 1 concurrent job. On top of this, it has a special Free Tier for open source projects, which extend the number of containers and concurrent jobs available.

Yes

Pricing is based on amount of users for both the cloud and on premise versions. The cloud offering has different tiers depending on build times and storage.

Yes

Provides a calculator, based on the number of concurrent jobs and containers, which can be used to determine pricing before purchase. They also give a guideline based on the number of developers you employ (2-3 containers per full-time developer)

Yes

Dedicated tehnical support.

Yes

While it's community is not quite as vibrant as it is for Jenkins, CircleCI even offers support premium support for companies who cannot afford any downtime in their CI/CD pipelines (https://circleci.com/support/premium-support/). For the regular plans, all plans except the free tier offer official email support. The free tier only includes community support (Discuss, StackOverflow, etc.)

Yes

Yes

CircleCI can run builds in parallel, each build in a completely isolated environment by using containers.

N/A

Documentation is unclear, but it's reasonable to assume that distributed builds for the on premise version are not an issue.

Yes

The SaaS version distributes builds by default, while the self-hosted version has all the tools built-in for managing the cluster of builder machines.

Yes

Yes

CircleCI runs every build in a container, or VM, ensuring an isolated, local scope for each build. The environment is also reset with each build, which can highlight hard-to-track issues related to assumptions about the environment that the project is deployed to.

Yes

Excellent overview and contextual feedback.

Yes

Available by default in Circle CI: https://circleci.com/docs/2.0/status/#section=jobs. Aditionally, the Insights Dashboard provides a very useful overview on build times, error rates and status for your projects: https://circleci.com/docs/2.0/insights/#section=jobs

Yes

No (partial)

Using the Cloud plan for Circle CI requires no dedicated person for maintanence / management of the service. The CircleCI Server option (self-hosted) is also hassle free, as the process of installing and managing CircleCI and it's dependencies is automated. Developers are also given SSH acces to the builds (not the whole environment), while sys-admins can work on the host machine without worry about affecting the builds (which are containerized).

Yes

Yes

Yes

Yes

Yes

Yes

Pipelines in CircleCI are defined declaratively using an Yaml config file. CircleCI has special provisions for storing secrets in these files.

Yes

Yes

Reports are available

Yes

Large collection of available apps: https://confluence.atlassian.com/bitbucket/apps-and-integrations-675189068.html

Yes, partially

While CircleCI doesn't natively support plugins, it's core features address all of the core functionality that a CI/CD service needs. For integrating with other platforms or tools, there are integrations such as https://slack.com/apps/A0F7VRE7N-circleci. Certain jobs are available as CircleCI Orbs: https://circleci.com/orbs/

Yes

Clear, concise documentation on setting up a Ruby project with Bitbucket pipelines: https://confluence.atlassian.com/bitbucket/ruby-with-bitbucket-pipelines-872005618.html

Yes

For collecting test metadata and coverage, there is built-in support for Ruby (specifically, Cucumber and RSpec). Setting this up takes very little time and is well-documented on CircleCI's docs.

Yes

Clear, concise documentation on setting up a Javascript project with Bitbucket pipelines: https://confluence.atlassian.com/bitbucket/javascript-node-js-with-bitbucket-pipelines-873891287.html

Yes

For collecting test metadata and coverage, there is built-in support for Javascript. For code coverage, CircleCI understands Istanbul output (Jest also uses Istanbul for the code coverage reports), while for test metadata, the JUnit output format is natively supported.

Yes

Large collection of available integrations: https://confluence.atlassian.com/bitbucket/apps-and-integrations-675189068.html

Yes

Available as CircleCI Orbs: https://circleci.com/orbs/

Yes

Yes

REST API documentation available at https://circleci.com/docs/api/#api-overview. Creating Orbs is also documented at https://circleci.com/docs/2.0/orb-author/#introduction

Yes

N/A

There's some confusion regarding Bitbucket Pipelines and Bamboo, where they overlap and where not. Atlassian discontinued their Bamboo Cloud offering ~3 years ago, so at a high-level they are different products in that regard. What can be said about both is that they are top-tier tools for high-demand engineering teams, especially valuable as long as the other tools in the Atlassian suite are adopted (Bitbucket is a must for Bitbucket pipelines, being just one if it's features, but other tools like Jira are not to be dismissed either). It does seem like Bitbucket Pipelines is the more mature product of the two though.