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+# Compilation
+
+For more details and other workflows see the "Advanced guide" below.
+
+## Checking out the code
+
+```bash
+git clone https://github.com/libjxl/libjxl.git --recursive --shallow-submodules
+```
+
+This repository uses git submodules to handle some third party dependencies
+under `third_party`, that's why it is important to pass `--recursive`. If you
+didn't check out with `--recursive`, or any submodule has changed, run:
+
+```bash
+git submodule update --init --recursive --depth 1 --recommend-shallow
+```
+
+The `--shallow-submodules` and `--depth 1 --recommend-shallow` options create
+shallow clones which only downloads the commits requested, and is all that is
+needed to build `libjxl`. Should full clones be necessary, you could always run:
+
+```bash
+git submodule foreach git fetch --unshallow
+git submodule update --init --recursive
+```
+
+which pulls the rest of the commits in the submodules.
+
+Important: If you downloaded a zip file or tarball from the web interface you
+won't get the needed submodules and the code will not compile. You can download
+these external dependencies from source running `./deps.sh`. The git workflow
+described above is recommended instead.
+
+## Installing dependencies
+
+Required dependencies for compiling the code, in a Debian/Ubuntu based
+distribution run:
+
+```bash
+sudo apt install cmake pkg-config libbrotli-dev
+```
+
+Optional dependencies for supporting other formats in the `cjxl`/`djxl` tools,
+in a Debian/Ubuntu based distribution run:
+
+```bash
+sudo apt install libgif-dev libjpeg-dev libopenexr-dev libpng-dev libwebp-dev
+```
+
+We recommend using a recent Clang compiler (version 7 or newer), for that
+install clang and set `CC` and `CXX` variables.
+
+```bash
+sudo apt install clang
+export CC=clang CXX=clang++
+```
+
+## Building
+
+```bash
+cd libjxl
+mkdir build
+cd build
+cmake -DCMAKE_BUILD_TYPE=Release -DBUILD_TESTING=OFF ..
+cmake --build . -- -j$(nproc)
+```
+
+The encoder/decoder tools will be available in the `build/tools` directory.
+
+## <a name="installing"></a> Installing
+
+```bash
+sudo cmake --install .
+```
+
+
+
+## Advanced guide
+
+### Building with Docker
+
+We build a common environment based on Debian/Ubuntu using Docker. Other
+systems may have different combinations of versions and dependencies that
+have not been tested and may not work. For those cases we recommend using the
+Docker container as explained in the
+[step by step guide](doc/developing_in_docker.md).
+
+### Building JPEG XL for developers
+
+For experienced developers, we provide build instructions for several other environments:
+
+*   [Building on Debian](doc/developing_in_debian.md)
+*   Building on Windows with [vcpkg](doc/developing_in_windows_vcpkg.md) (Visual Studio 2019)
+*   Building on Windows with [MSYS2](doc/developing_in_windows_msys.md)
+*   [Cross Compiling for Windows with Crossroad](doc/developing_with_crossroad.md)
+
+If you encounter any difficulties, please use Docker instead.