WebAssembly Feature Detection

A small library (~560B gzip’d) to detect which features of WebAssembly are supported in your current browser.

Installation

npm install -g wasm-feature-detect

Usage

<script type="module">
  import { simd } from "https://unpkg.com/wasm-feature-detect?module";

  simd().then(simdSupported => {
    if (simdSupported) {
      /* SIMD support */
    } else {
      /* No SIMD support */
    }
  });
</script>

If required, there’s also a UMD version

<script src="https://unpkg.com/wasm-feature-detect/dist/umd/index.js"></script>
<script>
  wasmFeatureDetect.simd().then(/* same as above */);
</script>

Detectors

All detectors return a Promise<bool>.

Function	Proposal
bulkMemory()	Bulk memory operations
exceptions()	Exception handling
multiValue()	Multi-value
mutableGlobals()	Importable/Exportable mutable globals
referenceTypes()	Reference Types
saturatedFloatToInt()	Non-trapping float-to-int conversions
signExtensions()	Sign-extension operators
simd()	Fixed-Width SIMD
tailCall()	Tail call
threads()	Threads

Why are all the tests async?

The technical reason is that some tests might have to be augmented to be asynchronous in the future. For example, Firefox is planning to make a change that would require a postMessage call to detect SABs, which are required for threads.

The other reason is that you should be using WebAssembly.compile, WebAssembly.instantiate, or their streaming versions WebAssembly.compileStreaming and WebAssembly.instantiateStreaming, which are all asynchronous. You should already be prepared for asynchronous code when using WebAssembly!

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License Apache-2.0