Add initial version of the Developer Guide

README.md

@@ -138,6 +138,8 @@ This project has adopted the [Microsoft Open Source Code of Conduct](https://ope
 For more information see the [Code of Conduct FAQ](https://opensource.microsoft.com/codeofconduct/faq/) or
 contact [[email protected]](mailto:[email protected]) with any additional questions or comments.
 
+Please read the [Developer Guide](eng/doc/DeveloperGuide.md) for more information about contributing to this project.
+
 ## Trademarks
 
 This project may contain trademarks or logos for projects, products, or services. Authorized use of Microsoft 

eng/doc/DeveloperGuide.md

@@ -0,0 +1,80 @@
+# Developer Guide
+
+This document is a guide for developers who want to contribute to the Microsoft Go repository.
+It explains how to build the repository, how to work with the Go submodule, and how to use the different tools
+that help maintain the repository.
+
+## Setting up the repository
+
+### Step 0: Contributor License Agreement
+
+Most contributions require you to agree to a Contributor License Agreement (CLA) declaring that you have the right to, and actually do, grant us the rights to use your contribution.
+For details, visit https://cla.opensource.microsoft.com.
+
+### Step 1: Install a Go toolchain
+
+A preexisting Go toolchain is required to bootstrap the build process.
+You can use your system's package manager to install Go, or you can download it from the [official Go website](https://golang.org/dl/).
+The only requirement is that the Go version is high enough for the bootstrap process.
+If the version is too low, the bootstrap process will fail and ask you to install a newer version.
+
+### Step 2: Install the git-go-patch command
+
+The `git-go-patch` command is a tool that helps you manage the patches in the `go` submodule.
+
+To install the `git-go-patch` command, run the following command:
+
+```
+go install github.com/microsoft/go-infra/cmd/go-patch@latest
+```
+
+> [!NOTE]
+> Make sure `git-go-patch` is accessible in your shell's `PATH` variable.
+> You may need to add `$GOPATH/bin` to your `PATH`. Use `go env GOPATH` to locate it.
+
+Then, run the command to see the help documentation:
+
+```
+git go-patch -h
+```
+
+> [!NOTE]
+> `git` detects that our `git-go-patch` executable starts with `git-` and makes it available as `git go-patch`.
+> The program still works if you call it with its real name, but we think it's easier to remember and type something that looks like a `git` subcommand.
+
+### Step 2: Initialize the submodule and apply patches
+
+The repository uses a `go` submodule to store the Go source code.
+All the patches that modify the Go source code are stored in the `patches` directory.
+
+To initialize the submodule and apply the patches, run the following command:
+
+```
+git go-patch apply
+```
+
+### Step 3: Build the Go toolchain
+
+You now can edit the `go/src` directory as you would any other Go project.
+
+Note that the `go/src/go.mod` file uses a `go` directive with a version that is not available as a prebuilt binary.
+This is because that module contains the future version of Go, which is not yet released.
+In order to build the standard library packages located in `go/src` you will first need to build to Go toolchain from the `go/src` directory itself using the following command:
+
+```
+cd go/src
+./make.bash # or make.bat on Windows
+```
+
+After building the Go toolchain, you can use it to develop and test changes in the `go/src` directory.
+You will need to add the `go/bin` directory to your `PATH` to use the new Go toolchain.
+
+### Step 4: Test that your environment is set up correctly
+
+To test that your environment is set up correctly, run the following command:
+
+```
+cd go/src
+go version
+go test -short ./...
+```