As the Platform Steering Group accepted the vision document for WebAssembly support, we’re excited to announce that Swift SDKs for Wasm are now available at swift.org/install. The website now also hosts a getting started guide for Wasm with installation and build instructions.
You may notice "Swift SDKs" is in plural. The reason is that artifact bundles for Wasm distributed from swift.org include two Swift SDKs: one with the full feature set of the Swift standard library and Swift Testing, and the other with a subset of features available in Embedded Swift. The latter is a big improvement over previous Embedded Swift for Wasm build workflows, which frequently required a manually crafted set of options passed to the compiler and the linker. With new Embedded Swift SDK for Wasm, pass --swift-sdk option as for any other cross-compilation build to get a tiny binary. For example, a fully optimized print("Hello, World!") built with Embedded Swift SDK for Wasm is only 9.7 kB.
Another major addition is the inclusion of WasmKit in toolchains distributed from swift.org. This means you can use swift run with Swift SDKs to run WASI-compatible binaries on the command line. There's ongoing work to fully enable swift test in the same manner.
While Swift Testing (not compatible with Embedded Swift yet) is already available in the Swift SDK, Foundation and XCTest will be included for greater compatibility with existing code in future development snapshots.
As WebAssembly started as a community project, we'd like to thank everyone who helped us to get to this milestone over the years. Special thanks (in alphabetical order) to @al45tair, @bnbarham, @carsonkatri, @danielle, @daveverwer, @finestructure, @fjtrujy, @Geordie_J, @j-f1, @kabiroberai, @kateinoigakukun, @mishal_shah, @shial4, @STREGA, @yonihemi, and Zhuowei Zhang.
Can't wait to see what you build with Swift for Wasm!
