When comparing TeamCity vs Gitea, the Slant community recommends TeamCity for most people. In the question“What are the best continuous integration tools with Windows support?” TeamCity is ranked 2nd while Gitea is ranked 3rd. The most important reason people chose TeamCity is:
TeamCity has different installation packages for different operating systems. All the user needs to do is download the correct one and run it.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Easy installation
TeamCity has different installation packages for different operating systems. All the user needs to do is download the correct one and run it.
Pro Cross-platform build support
The fact that it is based on Java does not hinder TeamCity's ability to support different build environments. TeamCity in fact supports a large number of languages and tools for each of those languages (build runners and test frameworks).
Some of the languages/platforms that are supported include: Ruby, .NET, Java.
Pro Brilliant interface
The user interface of TeamCity is clear, well thought out and the dashboard is highly customizable.
Pro Supports build chains
The user can easily compose dependencies between builds by adding snapshot and artifact dependencies, all on the one screen. All output of upstream builds is available to downstream builds. Triggering sets off the entire build chain and supports re-running of the portions of the chain that failed.

Pro Well documented

Pro Extensible
TeamCity offers well defined APIs for extending, as well as a REST interface.
Pro Testing support
TeamCity supports both MSTest and NUnit (which is open source) to run tests.
Pro Best choice for .NET
Seems to be the best choice for .NET applications, but to be honest: if you stray from the default settings you will be in a lot of pain most of the time.
Pro Light-weight
Easy to install and setup. Can run on a VPS with 1 core CPU and 256MB RAM.
Pro Open source and maintained by community
Unlike Gogs, which is maintained primarily by its creator.
Pro Intuitive interface
Easy to navigate around and feels very natural in general.
Pro Non-memory consuming
Just like Gogs, but with new features and fixed bugs. Unlike GitLab which is enormous.
Pro Wiki and issues
Like GitHub, a wiki and issues (bugtracking) can be added to a repository.
Pro Fast pace of development
New features, constantly updated.
Pro Like Gogs but with faster bug fixes
If you love Gogs but were frustrated with the long wait for bugs to be fixed, this is for you.
Pro Most common platforms
Versions available for Linux, Mac and Windows. This is possible because Gitea is developed in the Go language which makes it compact and fast too. Only one executable is needed.
Pro Easy install with MariaDB back-end
No problems getting to work with MariaDB.
Pro Simple to install/written in GO
Pro Package Registry
Supports NuGet, npm, Cargo, Composer, Maven, RubyGems etc.
To work with the NuGet package registry, you can use command-line interface tools as well as NuGet features in various IDEs like Visual Studio.
Pro Runs perfect on a Raspberry Pi 3
Thanks to its light-weight and simple integration.
Pro Customizable Templates
All templates can be overridden.
Pro Focus only on key features
And if you want extra features, you can use web hooks.
Cons
Con Expensive
TeamCity has a free tier which includes a maximum of 100 build configurations and up to 3 build agents. If you want to add 10 more configurations and 1 more agent, it will cost $299; unless you choose to buy an enterprise license which starts at $1999.
Con Poor quality plugins
At least some of them do not work, probably because they're not updated to more recent TeamCity versions.
Con Inter-branch merges trigger emails to unrelated committers
Whenever an inter-branch merge occurs, TeamCity pulls up the first parent of the merge commit and sends them an e-mail. However, this sort of information would be more useful to the merge author.
