+With these dependencies installed, you can build the compiler in a `cmd.exe`
+shell with:
+
+```sh
+python x.py build
+```
+
+Currently, building Rust only works with some known versions of Visual Studio. If
+you have a more recent version installed and the build system doesn't understand,
+you may need to force rustbuild to use an older version. This can be done
+by manually calling the appropriate vcvars file before running the bootstrap.
+
+```batch
+CALL "C:\Program Files (x86)\Microsoft Visual Studio\2019\Community\VC\Auxiliary\Build\vcvars64.bat"
+python x.py build
+```
+
+#### Specifying an ABI
+
+Each specific ABI can also be used from either environment (for example, using
+the GNU ABI in PowerShell) by using an explicit build triple. The available
+Windows build triples are:
+- GNU ABI (using GCC)
+ - `i686-pc-windows-gnu`
+ - `x86_64-pc-windows-gnu`
+- The MSVC ABI
+ - `i686-pc-windows-msvc`
+ - `x86_64-pc-windows-msvc`
+
+The build triple can be specified by either specifying `--build=<triple>` when
+invoking `x.py` commands, or by copying the `config.toml` file (as described
+in [Installing From Source](#installing-from-source)), and modifying the
+`build` option under the `[build]` section.
+
+### Configure and Make
+
+While it's not the recommended build system, this project also provides a
+configure script and makefile (the latter of which just invokes `x.py`).
+
+```sh
+./configure
+make && sudo make install
+```
+
+When using the configure script, the generated `config.mk` file may override the
+`config.toml` file. To go back to the `config.toml` file, delete the generated
+`config.mk` file.
+
+## Building Documentation
+
+If you’d like to build the documentation, it’s almost the same:
+
+```sh
+./x.py doc
+```
+
+The generated documentation will appear under `doc` in the `build` directory for
+the ABI used. I.e., if the ABI was `x86_64-pc-windows-msvc`, the directory will be
+`build\x86_64-pc-windows-msvc\doc`.
+
+## Notes
+
+Since the Rust compiler is written in Rust, it must be built by a
+precompiled "snapshot" version of itself (made in an earlier stage of
+development). As such, source builds require a connection to the Internet, to
+fetch snapshots, and an OS that can execute the available snapshot binaries.
+
+Snapshot binaries are currently built and tested on several platforms:
+
+| Platform / Architecture | x86 | x86_64 |
+|---------------------------------------------|-----|--------|
+| Windows (7, 8, 10, ...) | ✓ | ✓ |
+| Linux (kernel 3.2, glibc 2.17 or later) | ✓ | ✓ |
+| macOS (10.7 Lion or later) | (\*) | ✓ |
+
+(\*): Apple dropped support for running 32-bit binaries starting from macOS 10.15 and iOS 11.
+Due to this decision from Apple, the targets are no longer useful to our users.
+Please read [our blog post][macx32] for more info.
+
+[macx32]: https://blog.rust-lang.org/2020/01/03/reducing-support-for-32-bit-apple-targets.html
+
+You may find that other platforms work, but these are our officially
+supported build environments that are most likely to work.
+
+## Getting Help
+
+The Rust community congregates in a few places:
+
+* [Stack Overflow] - Direct questions about using the language.
+* [users.rust-lang.org] - General discussion and broader questions.
+* [/r/rust] - News and general discussion.
+
+[Stack Overflow]: https://stackoverflow.com/questions/tagged/rust
+[/r/rust]: https://reddit.com/r/rust
+[users.rust-lang.org]: https://users.rust-lang.org/
+
+## Contributing
+
+If you are interested in contributing to the Rust project, please take a look
+at the [Getting Started][gettingstarted] guide in the [rustc-dev-guide].
+
+[rustc-dev-guide]: https://rustc-dev-guide.rust-lang.org