What is dotnet watch?

dotnet watch is a way to immediately trigger a dotnet command when a file changes. The most common uses for this are using it to automatically re-run your application (using dotnet watch run) or automatically re-run your tests (using dotnet watch test) after a file change. This obviously speeds up your workflow so you don’t have to restart your server or your tests manually.

A new feature of dotnet watch run in .NET 5+ is that it will automatically launch a browser and auto-refresh the browser after it detects a change and finishes compiling (if your application has a UI).

What is JetBrains Rider?

JetBrains Rider is a cross-platform .NET IDE from the people at JetBrains (who make many developer productivity tools such as Resharper for Visual Studio, TeamCity, IntelliJ, and more). It is my go-to IDE now, due to all of its productivity enhancements over the base install of Visual Studio. I’ve been a user of Resharper for years, but Resharper and Visual Studio never seemed to play very nice together and ended up slowing down Visual Studio significantly. I put up with it due to all the extra functionality Resharper provided.

With Rider, I get all the benefits of Resharper and it’s fast. I can use Rider on Windows or macOS (which I bounce between for personal and professional work), and a lot of features are included for $150 that I would have to spend thousands to get in Visual Studio Enterprise (such as Continuous Testing).

How do I integrate dotnet watch and Rider?

Alright, now for the part you came here for. Obviously, you could run dotnet watch run directly using the terminal, but it’d be nice to have this as a launch configuration option right in Rider that is only a CTRL + F5 away. Here’s how to do that:

1. Open your solution in Rider
2. Select your Configuration and hit Edit Configurations

3. Click the Plus in the top left to Add New Configuration

5. Choose Native Executable (Note: you CAN search)

6. Give it a Name, I called mine dotnet watch
7. For “Exe path” choose C:\Program Files\dotnet\dotnet.exe if you’re on Windows or /usr/local/share/dotnet/dotnet if you’re on macOS
8. For “Program arguments” type watch run
9. For “Working directory” choose the directory that your application’s csproj resides in.
10. For “Environment variables” You could add ASPNETCORE_ENVIRONMENT=Development if it’s an ASP.NET Core app, but the environment variables defined in your launchSettings.json will take precedence (under the node that contains "command name": "project").
11. The final output should look like this:

12. Hit OK

13. Now start the app with your new configuration selected

14. That’s it! You’ll notice that your Run tab of Rider will now show your watch command running

That’s it!

I hope this helps someone else. An example of this in action is below:

Note: auto-attaching the debugger does not work with this option in Rider. The issue to track that is here if you want to give that a thumbs up to vote for JetBrains to work on that feature in an upcoming release.