How to: Ensure LESS works with ASP.NET MVC and Continuous Integration [Field Notes]

Problem:

• I use LESS instead of CSS in my ASP.NET MVC app.
• I would like it to actually work.

Solution

There are two steps (that I know of) to fixing this problem. The first is to make sure that your build package will actually output the LESS files in the first place; the second is to ensure that IIS can serve them.

Step 1: Ensuring that the Build Package outputs LESS files

• In your solution, highlight all your LESS files
• Right-click and select properties or look in the properties window.
• Set the Build Action property to Content. This will ensure that the raw content is outputted from those files during build instead of another build action.
• Set the Copy to Output Directory property to Copy Always. This ensures that your LESS files will actually make it into the package folder that MSBuild outputs.

Step 2: Ensuring that IIS can serve LESS files

• See the instructions in my post titled When using Twitter Bootstrap LESS with IIS, don’t forget to create the MIME Type