corefx. This repository contains the foundational libraries that make up the .NET Core development stack.
10corert. This repo contains CoreRT, a .NET Core runtime optimized for AOT (ahead of time compilation) scenarios, with the accompanying .NET Native compiler toolchain.
4coreclr. This repo contains the .NET Core runtime, called CoreCLR. It is an execution engine for .NET apps, performing functions such as IL byte code loading, compilation to machine code and garbage collection. The repo contains the complete up-to-date CoreCLR codebase.
3cli. This repo contains the .NET Core command-line (CLI) tools, used for building .NET Core apps and libraries through your development flow (compiling, NuGet package management, running, testing, ...).
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