Initial commit

README.md

@@ -0,0 +1,43 @@
+# wasm-sdk
+
+A SDK for LLVM C and C++ WebAssembly development based on Nix.
+
+It builds all required dependencies (*clang, clang++, wasm-ld, libcxx, compiler-rt*, and *wasi-libc*)
+and exposes the following environment variables needed to compile to WebAssembly, for example:
+
+```
+WASM_LLVM=/nix/store/akpcpb9ycb98jjbp6dyg1j65vkwqp1lm-wasm-llvm
+WASM_LIBCXX_LIB=/nix/store/ll4hi2jkhv8399dhbz6q0qgw97c6hyja-wasm-libcxx/lib
+WASM_LIBCXX_INC=/nix/store/ll4hi2jkhv8399dhbz6q0qgw97c6hyja-wasm-libcxx/include/c++/v1
+WASM_COMPILER_RT_LIB=/nix/store/59lmk928vly8126zq7mabzc9123hknj2-wasm-compiler-rt/lib/wasi
+WASI_LIBC_LIB=/nix/store/qislis4ivwv3l721dbhghax6j4kp3ccb-wasi-libc/lib
+WASI_LIBC_INC=/nix/store/71k5vk20275571n0bsij42qdasbxc82b-wasi-libc-dev/include
+```
+
+## Goals
+
+* Lean toolchain leveraging as much as possible from upstream sources.
+* Basic levels of WASI (no threading, no exceptions).
+
+
+## Versions
+
+* LLVM: 17
+* wasi-libc: 21
+
+
+## Usage
+
+The included derivation produces a single file with exportable environment variables.
+
+Example:
+
+```sh
+env $(cat $(nix-build -E 'with import <nixpkgs> {}; callPackage ./default.nix {}')) printenv
+```
+
+A *flake* is also included that exposes the needed variables in the following ways (three ways to choose from, for convenience):
+
+1. as the `paths` (*attrset* type) *passthru* of the *derivation* of the *default package* (to use in other *flakes*).
+2. as exported environment variables in the *default development shell* (`nix develop`).
+3. as text in a file (`nix build` produces the file `./result`).