JetBrains TeamCity is a continuous integration and delivery (CI/CD) server developed by JetBrains. It is designed to help developers and IT operations teams automate their application development and release processes. TeamCity provides a web-based UI, allowing developers to quickly and easily set up automated workflows, such as build pipelines, deployments, and tests. It supports multiple languages and technologies, making it a great tool for developers of all backgrounds. TeamCity also integrates with other popular tools, like GitHub, JIRA, and Slack, so teams can easily collaborate and share information. It also provides powerful reporting capabilities, so teams can get real-time insights into their application development processes.
They just overlap a bit in deployment options. TeamCity is a complete continuous integration package, Octopus Deploy is a deployment manager with some build services.