Based on our record, LambCI seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Your Docker suggestion is spot on. Only variation would be not to use Ubuntu (its not what Lambda uses) but use a Docker image tuned to have a Lambda compatible runtime like one of the lambci images. https://github.com/lambci/lambci. Source: about 2 years ago
Jenkins - Jenkins is an open-source continuous integration server with 300+ plugins to support all kinds of software development
Semaphore - Semaphore is a fully managed, high performance testing and deployment solution for your company. A Continuous Integration tool.
CircleCI - CircleCI gives web developers powerful Continuous Integration and Deployment with easy setup and maintenance.
TeamCity - TeamCity is an ultimate Continuous Integration tool for professionals
Travis CI - Focus on writing code. Let Travis CI take care of running your tests and deploying your apps.
Bitrise - Tens of thousands of agencies, startups and enterprise companies with mobile apps - including Runkeeper, Grindr, Duolingo and more - use Bitrise to automate their way to increased productivity & speed