Microsoft released .NET Core as open source. Find out what's inside!

Microsoft announced that .NET Core will be open source, including the runtime and the framework libraries.
There are several open source Microsoft .NET projects on GitHub and CodePlex:

• .NET Core 5 (corefx) - foundational libraries that make up the .NET Core development stack;
• .NET Core 5 buildtools - Build tools that are necessary for building the .NET Core project;
• .NET Compiler Platform (Roslyn) - open-source C# and Visual Basic compilers with rich code analysis APIs;
• EntityFramework - Microsoft's recommended data access technology for new applications in .NET;
• ASP.NET vNext Home - The Home repository is the starting point for people to learn about ASP.NET vNext;

So what's in this stuff, anyway? Let's dissect it using sloccount and cloc (count lines of code) and find out!

Grab the code for Roslyn:

$ GIT_CURL_VERBOSE=1 git clone -v https://git01.codeplex.com/roslyn

Cloning into 'roslyn'...
error: RPC failed; result=56, HTTP code = 200
GnuTLS recv error (-9): A TLS packet with unexpected length was received.

Whatever - no time to rebuild git against OpenSSL. Let's use a workaround:

$ mkdir roslyn; cd roslyn; git init
$ git remote add origin https://git01.codeplex.com/roslyn
$ git checkout -B master origin/master

Great. Now let's grab the .NET Core dev stack, libraries and build tools (github clones fine):

$ git clone https://github.com/dotnet/corefx.git
$ git clone https://github.com/dotnet/buildtools.git

Analyze the .NET Core 5 (corefx) and buildtools

$ cloc --xsl=1 --xml corefx/ buildtools/

Language	Files	Blank	Comment	Code
C#	565	17312	24750	104192
XML	2	0	7	4456
MSBuild scripts	15	54	90	1820
SKILL	2	11	0	52
Visual Basic	1	17	1	43
ASP.Net	6	0	0	32
C/C++ Header	1	5	1	7
DOS Batch	1	0	0	5
Total	593	17399	24849	110607

Analyze Roslyn

$ cloc --xsl=1 --xml roslyn/Src

Language	Files	Blank	Comment	Code
C#	4138	186147	131956	1173792
Visual Basic	1767	178277	140738	981301
XML	4	1870	1920	12451
MSBuild scripts	74	0	216	10066
C/C++ Header	15	1607	428	7361
SKILL	33	888	0	4954
C++	12	322	186	1698
XSD	3	74	217	401
ASP.Net	44	4	0	351
XAML	3	3	1	128
DOS Batch	6	22	11	79
PowerShell	3	7	0	13
Total	6102	369221	275673	2192595

$ sloccount roslyn/Src

Total Physical Source Lines of Code (SLOC)                = 1,205,824
Development Effort Estimate, Person-Year (Person-Month) = 343.86 (4,126.29)
 (Basic COCOMO model, Person-Months = 2.4 * (KSLOC**1.05))
Schedule Estimate, Years (Months)                         = 4.93 (59.14)
 (Basic COCOMO model, Months = 2.5 * (person-months**0.38))
Estimated Average Number of Developers (Effort/Schedule)  = 69.78
Total Estimated Cost to Develop                           = $ 46,450,431
 (average salary = $56,286/year, overhead = 2.40).

So - what have we learned?

• sloccount COCOMO estimates are just that - estimates;
• We have over one million lines of C# to play around with;
• Porting this thing will likely depend on Mono and will require quite a lot of work;
• It still doesn't make up an ecosystem - there's work to be done here to turn this into a cross-platform .NET environment;
• Microsoft is most likely pushing for the clouds - this open source seems consistent with their recent partnership with Docker.