cloudflare-workers

quickjs-emscripten + cloudflare workers

Cloudflare Workers need some extra setup steps because of the unusual environment and limitations with the bundling defaults, because Cloudflare refuses to let us read these files and compile them from bytes.

1. We need to copy the WASM files for the QuickJS variants in use into the src directory, so we can import them directly. The script copy-wasm-file-into-src.sh does this. You should copy it to your project, and run it whenever you update quickjs-emscripten to a new version. It will copy the WASM and SourceMap files from node_modules into the src directory every time you run it.
   • This creates the files src/DEBUG_SYNC.wasm and src/DEBUG_SYNC.wasm.map.txt. Add them to your .gitignore.
2. We need to override the normal loading behavior to use the special imported WebAssembly.Module. See src/index.mts. Copy and paste the code in index.mts into your project, or do something similar:
   • import the quickjs-emscripten WASM files directly, like import wasmModule from './DEBUG_SYNC.wasm'.
   • import the quickjs-emscripten SourceMap.txt files directly as well, like import wasmSourceMapData from './DEBUG_SYNC.wasm.map.txt'.
   • create a new variant using those files: const cloudflareVariant = newVariant(DEBUG_SYNC, { wasmModule, wasmSourceMapData }).
   • Instead of using await getQuickJS(), use newQuickJSWASMModule(cloudflareVariant).