I miss the days of MASM and Codeview. I used to debug DOS programs in Codeview and could step into and out of code lines and even modify the code. By changing a JE to JNE I was able to bypass the Lotus 123 2.0 protection so it could be installed on a Netware drive instead of just a floppy disk.<p>GDB/LLDB it is good that Microsoft is open sourcing their debug tools. Microsoft has been struggling with improving Visual Studio and Dotnet, so in open sourcing them or parts of them in CoreCLR, Visual Studio Core, and then GDB/LLDB they are letting open source developers participate in improving them.<p>Sure it isn't the full version of Visual Studio, I don't expect Microsoft to give away everything but small parts of it. Sometimes less is more, in that the fewer lines of code the smaller the program the faster it runs.<p>I would like to see an Office Core and SQL Server Core as well if they can.