I still fail to see the heavily opinionated appeal of CircleCI over running a dockerized Jenkins instance (and agents) in AWS. (Or GitHub Actions or any other managed CI environment)
We get all the customization I want and it scales just fine.
But I am also still annoyed that when CircleCI announced their templates, they did not offer you the ability to have private templates (or something along those lines, it left a bad taste in my mouth and we moved to Jenkins a couple months later)
I used CircleCI a long time ago, just before and after 2.0, and thought it was fine.
These days GitHub Actions is awesome and full featured and does everything I want though without getting in the way. I doubt I'd use anything besides GHA unless I wanted to decouple from GitHub as a dependency.
Even then, I wouldn't be surprised if someone else hasn't already come up with an open source or local runner for the GHA yaml files as a stopgap.
Two downsides of GHA that I could find:
- you are limited to 2 core / 7 GB instance, whereas CircleCI offers up to 16 cores / 64 GB (for example, building software usually scales proportionately to machine size, and this can in theory be up to 8x faster on CircleCI)
- no support for ARM instances
GHA also supports bringing your own self-hosted runners [1][2] where you install their agent, so you could, e.g., use an ARM instance on AWS with tons of cores. It looks like CircleCI offers this as well.
[1]: https://docs.github.com/en/actions/hosting-your-own-runners/...