IIS 7 ASP.Net 4 - Code Behind Auto Compile Not Working

I fired up my first asp.net 4 app put together with visual studio 2010 and IIS doesn't seem to compile my code behinds on the fly for some reason, I have to build the site manually.

How d开发者_开发问答o I configure my app to compile code behinds on the fly? I looked around but I must be missing something. Never had this issue before.

Thanks all,

bd

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There are now two web site types Web Application and Web site. The former must be pre-compiled, the latter can be compiled on the fly.

You create Web Application from File > New > Project... You create Web Site from File > New > Web site...