⚠️The rules in this repository are in the beta stage of development. There are many features that still need to be implemented and there may be bugs. If you run into any problems, please file an issue!
This repository contains rules for Bazel that can be used to build Swift libraries and executables for Apple platforms (iOS, macOS, tvOS, and watchOS) and Linux.
NOTE: The build rules in this repository are intended to replace the
swift_library rule that is currently housed in
Click here for the reference documentation for the rules and other definitions in this repository.
These rules have been verified to work with Bazel 0.16.0.
1. Install Swift
Before getting started, make sure that you have a Swift toolchain installed.
Apple users: Install Xcode. If this is your first time installing it, make sure to open it once after installing so that the command line tools are correctly configured.
Linux users: Follow the instructions on the Swift download page to download and install the appropriate Swift toolchain for your platform. Take care to ensure that you have all of Swift's dependencies installed (such as ICU, Clang, and so forth), and also ensure that the Swift compiler is available on your system path.
2. Configure your workspace
Add the following to your
WORKSPACE file to add the external repositories,
replacing the version number in the
tag attribute with the version of the
rules you wish to depend on:
git_repository( name = "build_bazel_rules_swift", remote = "https://github.com/bazelbuild/rules_swift.git", tag = "0.3.0", ) load( "@build_bazel_rules_swift//swift:repositories.bzl", "swift_rules_dependencies", ) swift_rules_dependencies()
swift_rules_dependencies macro creates a toolchain appropriate for your
platform (either by locating an installation of Xcode on macOS, or looking for
swiftc on the system path on Linux).
3. Additional configuration (Linux only)
swift_test rules expect to use
clang as the driver
for linking, and they query the Bazel C++ API and CROSSTOOL to determine which
arguments should be passed to the linker. By default, the C++ toolchain used by
gcc, so Swift users on Linux need to override this by setting the
CC=clang when invoking Bazel.
This step is not necessary for macOS users because the Xcode toolchain always
- Support for building and linking to shared libraries (
.so) written in Swift.
- Interoperability with Swift Package Manager.
- Improved C interoperability.
- Migration to the Bazel platforms/toolchains APIs.
- Support for multiple toolchains, and support for non-Xcode toolchains on macOS.
- Automatically download a Linux toolchain from swift.org if one is not already installed.