+#### 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=ABI` when
+invoking `x.py` commands, or by copying the `config.toml` file (as described
+in Building 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.
+