--- /dev/null
+# Dependencies
+
+Before you can start compiling tinc from a fresh git clone, you have
+to install the very latest versions of the following packages:
+
+- `meson`
+- `ninja`
+- `pkgconf` or `pkg-config`
+- `GCC` or `Clang` (any version with C11 support, although older versions might work)
+- `OpenSSL`\* (1.1.0+) or `LibreSSL` or `libgcrypt` (not needed if legacy protocol is disabled)
+
+Plus a few optional dependencies. Support for them will be enabled if they're present:
+
+- `ncurses` or `PDCurses`
+- `readline`
+- `zlib`\*
+- `LZO`\*
+- `LZ4`\*
+
+If packages marked by `*` are not available, tinc will fall back to its own vendored copies.
+This behavior can be disabled by setting the appropriate meson option to `disabled`.
+
+To build `info` documentation you'll also need these packages:
+
+- `texinfo` or `makeinfo`
+
+You might also need some additional command-line utilities to be able to run the integration test suite:
+
+- `diffutils`
+- `procps`
+- `socat`
+- `netcat`
+
+Please consult your operating system's documentation for more details.
+
+## Windows
+
+You will need to install [msys2][msys2] to build tinc under Windows.
+
+[msys2]: https://msys2.org/
+
+By default, tinc produces a static Windows build, so you don't need to install anything
+in order to _run_ the compiled binaries.
+
+# Building
+
+## Native
+
+Have a look at the available configuration options in `meson_options.txt`, or run:
+
+ $ meson configure
+
+The project can be built as any other meson project:
+
+ $ meson setup build -Dprefix=/usr/local -Dbuildtype=release
+
+This creates a build directory (named `build`) with build type set to `release`
+(which enables compiler optimizations) and path prefix set to `/usr/local`.
+
+Pass any additional options in the same way. Typically, this is not needed: tinc will
+autodetect available libraries and adjust its functionality accordingly.
+
+If you'd like to reconfigure the project after running `setup`, you can either remove
+the build directory and start anew, or use:
+
+ $ meson configure build -Dlzo=disabled -Dlz4=enabled
+
+You then need to build the project:
+
+ $ ninja -C build
+
+You might want to run the test suite to ensure tinc is working correctly:
+
+ $ ninja -C build test
+
+To install tinc to your system, run:
+
+ # ninja -C build install
+
+Please be aware that this is not the best method of installing software
+because it will not be tracked by your operating system's package manager. You
+should use packages provided by your operating system, or build your own
+(this is a large and complicated topic which is out of the scope of this document).
+
+To uninstall tinc, run:
+
+ # ninja -C build uninstall
+
+## Cross-compilation
+
+### Linux to Linux
+
+Cross-compilation is easy to do on Debian or its derivatives.
+Set `$HOST` to your target architecture and install the cross-compilation toolchain and `-dev` versions of all libraries you'd like to link:
+
+ $ HOST=armhf
+ $ dpkg --add-architecture $HOST
+ $ apt update
+ $ apt install -y crossbuild-essential-$HOST zlib1g-dev:$HOST …
+
+If you'd like to run tests on emulated hardware, install `qemu-user`:
+
+ $ apt install -y qemu-user
+ $ update-binfmts --enable
+
+Set two environment variables: the C compiler, and pkg-config, and then proceed as usual:
+
+ $ export CC=arm-linux-gnueabihf-gcc
+ $ export PKG_CONFIG=arm-linux-gnueabihf-pkg-config
+ $ meson setup build --cross-file /dev/null
+
+or put the names into a [cross file][cross] and pass it to meson:
+
+ $ cat >cross-armhf <<EOF
+ [binaries]
+ c = 'arm-linux-gnueabihf-gcc'
+ pkgconfig = 'arm-linux-gnueabihf-pkg-config'
+ EOF
+
+ $ meson setup build --cross-file cross-armhf
+
+[cross]: https://mesonbuild.com/Cross-compilation.html
+
+### Linux to Windows
+
+Install cross-compilation toolchain:
+
+ $ apt install -y mingw-w64 mingw-w64-tools
+
+tinc will use its own vendored libraries, so you don't need to install or build anything manually.
+
+Prepare the [cross file][cross] to let meson know you're building binaries for a different opearting system.
+Take a look at the [file](.ci/cross/windows/amd64) used by CI for an example, or refer to examples provided
+by the meson project: [x86][mingw32], [x86_64][mingw64].
+
+Then build as usual. Because Windows binaries are built with static linkage by default,
+you might want to enable link-time optimization. It is much slower than building without LTO,
+but produces binaries that are 80%+ smaller:
+
+ $ meson setup build -Dbuildtype=release -Db_lto=true --cross-file cross-windows
+ $ ninja -C build
+
+[mingw64]: https://github.com/mesonbuild/meson/blob/master/cross/linux-mingw-w64-64bit.txt
+[mingw32]: https://github.com/mesonbuild/meson/blob/master/cross/linux-mingw-w64-32bit.txt
+
+### Linux to Android
+
+First you need to install [Android NDK][ndk].
+
+[ndk]: https://developer.android.com/studio/projects/install-ndk
+
+Prepare a [cross file][cross]. Here's a working example for reference:
+
+```ini
+[host_machine]
+system = 'android'
+cpu_family = 'arm'
+cpu = 'aarch64'
+endian = 'little'
+
+[binaries]
+c = 'aarch64-linux-android24-clang'
+```
+
+Then build as usual:
+
+ $ export ANDROID_NDK_ROOT=/tmp/ndk/android-ndk-r24
+ $ export PATH=$ANDROID_NDK_ROOT/toolchains/llvm/prebuilt/linux-x86_64/bin:$PATH
+ $ meson setup android-aarch64 -Dcrypto=nolegacy --cross-file android
+ $ ninja -C android-aarch64
+
+### macOS to iOS
+
+The same instructions should work for iOS.
+Refer to this [cross file][ios] for an example.
+
+[ios]: https://github.com/mesonbuild/meson/blob/master/cross/iphone.txt
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