Having set up ci/cd systems a few times previously by hand I've been happy so far with aws codestar.

It uses codecommit, codebuild, codepipeline, codedeploy, with permissions configured via iam. You can push to ec2, beanstalk or lambda.

I find beanstalk to be the sweet spot for ease of use with time saving abstractions. You can integrate jira too, and it enables cloudwatch for monitoring.

It's easy to set up. It sounds like Flexport's solution is more robust as they've done some great tweaks to their workflow, but for a quick ci/cd pipeline setup, codestar is pretty slick.