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A high-reliability, real-time, decentralized platform for collaborative autonomy. Tutorials for using Skywing can be found in documentation/tutorials. To first build Skywing, follow the instructions below.

Some dependencies are managed by Skywing's build process, and some you need to acquire yourself beforehand.

• compiler that supports c++17 library
  • tested: GCC/g++ (8.3.0) and LLVM/clang (6.0.0, 10.0.0, 11.0.0)
• meson (https://mesonbuild.com/)
  • requires Python >= 3.8.0
• CMake (https://cmake.org/)
• ninja (https://ninja-build.org/)
• Cap'n Proto (https://capnproto.org/)
  • requires version 0.8.0 or newer

You do not need to acquire these yourself.

• Catch2
• spdlog
• Guidelines Support Library (GSL)

Follow these instructions to build a "barebones" version of Skywing without any tests or examples.

• Build non-managed dependencies separately
• Get dependencies
  • git submodule update --init
• Create build files
  • mkdir build
  • meson build
• Build Skywing
  • cd build
  • ninja
• Run tests
  • meson test --print-errorlogs -t 5.0

Before creating the build directory, replace the meson build command with

meson build -Dbuild_tests=true -Dbuild_examples=true

If you are running on LLNL's LC clusters, these instructions can help you get set up.

• Cap'n Proto must be manually built first. Follow the instructions at https://capnproto.org/install.html#installation-unix, except you must build to a local directory. To do this, on the configure step, use
  • ./configure --prefix=capnp_build_dir
  • This will create subdirectories capnp_build_dir/bin, capnp_build_dir/include, and capnp_build_dir/lib

• Load meson (python), ninja, and switch to more recent version of gcc
  • 'ml python/3.8.2`
  • ml ninja
  • ml gcc/9.3.1
• Add capnp pkgconfig directory to PKG_CONFIG_PATH
  • export PKG_CONFIG_PATH=$PKG_CONFIG_PATH:capnp_build_dir/lib/pkgconfig
• Follow build instructions as normal
• To build the LC Hello World example, also include -Dbuild_lc_examples=true in the meson options.
• To run the LC example, go to (skywing_root)/build/examples/lc_hello_world/ and execute source run.sh (bank_name). Note that you must have an active bank to run this test.

• Add capnp shared library to LD_LIBRARY_PATH
  • export LD_LIBRARY_PATH=$LD_LIBRARY_PATH:capnp_build_dir/lib
• Run as normal for running on login node. Note: can't run long jobs on login nodes!
• Skywing configurations that involve many connections between agents can run into a file descriptor limit. The soft limit can be increased by executing ulimit -n <N> where <N> must not exceed the hard limit (which is determined by executing ulimit -Hn)

Note that Skywing configurations that involve many connections between agents can run into a file descriptor limit. The soft limit can be increased by executing ulimit -n <N> where <N> must not exceed the hard limit (which can be determined by executing ulimit -Hn)

Skywing is an open source project. We welcome contributions via pull requests as well as questions, feature requests, or bug reports via issues. Contact any of our team members with any questions. Please also refer to our code of conduct.

If you aren't a Skywing developer at LLNL, you won't have permission to push new branches to the repository. First, you should create a fork. This will create your copy of the Skywing repository and ensure you can push your changes up to GitHub and create PRs.

• Create your branches off the repo:main branch.
• Clearly name your branches, commits, and PRs as this will help us manage queued work in a timely manner.
• Articulate your commit messages in the imperative (e.g., Adds new privacy policy link to README).
• Commit your work in logically organized commits, and group commits together logically in a PR.
• Title each PR clearly and give it an unambiguous description.
• Review existing issues before opening a new one. Your issue might already be under development or discussed by others. Feel free to add to any outstanding issue/bug.
• Be explicit when opening issues and reporting bugs. What behavior are you expecting? What is your justification or use case for the new feature/enhancement? How can the bug be recreated? What are any environment variables to consider?

• Aly Fox fox33@llnl.gov
• Kendall Harter harter8@llnl.gov
• Colin Ponce ponce11@llnl.gov (corresponding author)
• Chris Vogl vogl2@llnl.gov

Skywing is distributed here under under the GPL v2.0 license, but a commercial license is also available. Users may choose either license, depending on their needs.

For the commercial license, please inquire at softwarelicensing@lists.llnl.gov.

LLNL-CODE-835832