GitLab CI is a good choice for new projects. It’s incrementally adoptable, self hostable, there are lots of people working on it, and it will probably be around for a while.
I had the misfortune of having to use GitLab CI recently. GitLab gets a lot of leeway from HN, maybe because it's an underdog, but it wasn't ready for prime time. Several features were just broken, and several more did things in surprising ways (not what you usually want to see in a key infrastructure component).
Definitely, it has its problems. The documentation also seems to lag behind the product (and there are duplicated pages for CE and EE, very confusing).
Personally it was easy for me to switch from travis because all my CI scripts are actually bash scripts, so the .yml CI file is just a few lines pointing to those scripts. All I had to do with gitlab was make a base image to be the "CI image" with all the tooling necessary + docker-in-docker.
I’m a “huge Github fanboy” and think GH Actions is poised to do to current CI/CD tooling what Docker did to VMs.. which actually scares me a little. GH is aiming to be the centre of the development world as Google is with the web... which I guess is good — rising tide lifts all boats and such — but personally I’m worried it might actually stifle innovation and create some sorta bullshit tech bubble because of how much emphasis recruiters and developers put on having a GitHub presence. If you use Bitbucket or GitLab you’re some second class scum! Fanboyism is bad folks. Anyways yea, Drone is sick :)
Not really a new hotness, but https://www.gocd.org/ is very good for building pipelines and graphs. Not so great for classical CI workloads (you can't say "test every branch that fits the pattern smokeme/*").
Upgrades to GoCD have been very predictable, in contrast to Jenkins :-)
