When comparing Phoenix vs ASP.NET Core, the Slant community recommends Phoenix for most people. In the question“What are the best backend web frameworks?” Phoenix is ranked 1st while ASP.NET Core is ranked 6th.
Specs
Ranked in these QuestionsQuestion Ranking
Pros
Pro Very positive reviews
Pro Relatively big community
It has the biggest community from all Elixir web frameworks so there are examples and tutorials all over the place and you can quickly find help.
Pro Easy to learn
The official guides are really well written.
Pro Will be easy to learn for Rails developers
Pro Fast and getting faster
Thanks to breakthroughs in ROSLYN compiler and the efforts of the .NET COre developer team, code written in C# can reach speeds just a step behind C++.
Pro Multi platform
Can run on Windows, Linux and Mac (also Visual Studio Code editor).
Pro JSON optimization
In .NET Core 2.1 and 3.0, new APIs are added that make it possible to write JSON APIs that require less memory, using Span<T> and UTF8 strings, and improve throughput of applications like Kestrel, ASP.NET Core web server. See also Utf8JsonReader.
Pro Tutorials and documentation quality
Both microsoft and 3rd party tutorials are mostly of high quality and encourage you to use the industry best-practices.
Pro Built-in middleware
Built-in middleware featuring: Authentication, Cookie policy, Health Check, MVC, Session etc.
Pro Hosting
Ability to host on IIS, Nginx, Apache, Docker, or self-host in your own process.
Pro Ease of Use
Pro Security
It is a very secure platform.
Pro Tooling
Both VS and VSCode are powerful free IDEs that are well integrated with ASP.net Core. VS Community also allows for commercial use for projects with less than 5 developers.