Good for CI/CD and also for automating smaller tasks

We use CircleCI for our CI/CD pipeline almost every single day. It manages and runs automated tests for all the remote branches, so we can catch issues before they escalate. When ever something gets merged into our dev, staging or master branches, it auto tests, builds and deploy all the infrastructure with Terraform and pushes the newer version to docker.

Pros

The pipelines can be broken into different steps, which makes debugging, managing and approving individual phases way easier. Also, looking at the logs and being able to share static permalinks to them is quite useful when you have larger teams. We all can see the progress of the building pipelines in real time and can debug and manage them. Great tool over all.

Cons

Sometimes it fails and doesn't immediately let's you go to debug the issue. Also, some settings for the VMs are tricky to set up right.

Great once you're all set up

Pros

- Easy to understand yaml config format - Integration with GitHub - Workflows for powerful deployment and release strategies - Good community support

Cons

- I am not the biggest fan of the recent UI update. If the "expand" toggle is set to true, everything jumps resulting in me clicking things unintentionally. - Many of us have workflows that we do not use on every push (e.g. deploying to testing). With the next UI changes, the UI has a timer column which is always updating, why??? - Why can't I select a default project? When I now browse to circleci, I always have to select a project. Most developers only ever work on one project at a time, let us choose one!

Does the job, but lacking in features

Pros

It's relatively simple to get started. I like that you can pick between Docker and VMs. It integrates with GitHub nicely.

Cons

The Docker in Docker paradigm doesn't work for us since we use containers. We end up using VMs anyways. I think the configuration language is not that great to use and can quickly get unwieldy for larger CI workflows (especially when repeating jobs with different parameters). There are also outages at least once a quarter.

Best in class continuous integration

My go-to on every SAAS product. Delivers the goods everytime.

Pros

It is incredibly easy to get started, you can be integrated in hours and from then on its a consistent reliable platform for all your CI needs.

Cons

As test suites grow and parallelization becomes important it can get awfully expensive. I still use it on every project but I was at a prior company where we racked up bills in the thousands a month without really trying for not that big a product. This was definitely due to some poor planning but CircleCI makes it easy to land yourself in that kind of situation if you're not careful.

One of the top CI/CD service

Pros

With a Github/Bitbucket account, it is easy to setup the CircleCI account. It automatically detects all the repositories. We can easily add the configuration file and start using the pipelines. Various customisation and parallelisation options are provided. Lot of possibilities for automation and customisation. Overall a good product.

Cons

It was bit of a hassle to start first, the configuration were not very easy. Also struggled a bit to manage various Github organisations. Once easy and setup, it's easy and fast.