perspective-dev/perspective · error · Error

WebAssembly not supported.

Error message

WebAssembly not supported.

What it means

The decompress module wraps `pro_self_extracting_wasm`, a self-extracting WebAssembly module used to decompress perspective assets. It performs an environment capability check at import time and throws immediately if the global `WebAssembly` object is undefined, because the module cannot function without WASM support.

Solutions

1. Run the application in a browser or Node.js version that supports WebAssembly (any modern browser; Node >= 8).
2. Check for CSP headers or enterprise policies disabling WebAssembly ('unsafe-eval'/'wasm-unsafe-eval' restrictions) and allow it.
3. If WASM cannot be enabled, avoid importing this module / the perspective packages that depend on it, or gate the import behind a WebAssembly support check.
4. Use a polyfill-free fallback: detect support with `typeof WebAssembly === "undefined"` before loading the library and show a graceful unsupported-browser message.

Example fix

// before
import { load_wasm } from "@finos/perspective"; // throws at import on WASM-less envs
load_wasm();

// after
if (typeof WebAssembly !== "undefined") {
  const { load_wasm } = await import("@finos/perspective");
  await load_wasm();
} else {
  console.error("This application requires WebAssembly support.");
}

if (typeof WebAssembly === "undefined") {
  console.warn("WebAssembly unsupported: perspective wasm modules will not load.");
}

function supportsWasm(): boolean {
  return typeof WebAssembly === "object" && typeof WebAssembly.Module === "function";
}

try {
  const decompress = await import("./wasm/decompress");
} catch (e) {
  if (e.message === "WebAssembly not supported.") {
    showUnsupportedBrowserDialog();
  } else throw e;
}

When it happens

Trigger: Importing (directly or transitively) rust/perspective-js's wasm/decompress.ts in any JavaScript environment that lacks `WebAssembly` — the check runs at module top level, so the error fires on import, not on a later call.

Common situations: Running in an old browser (IE11, pre-2017 Safari/Chrome/Firefox); Node.js < 8 without the --expose-wasm flag; embedded JS engines or SSR runtimes without WASM; CSP or enterprise policy disabling WebAssembly; webviews with WASM turned off.

Understand the failure class

Background: "unsupported platform" / "not supported on this platform" errors: what they mean and how to fix them — this error's family across 47 libraries.

Related errors

• Init error
• Missing perspective-client.wasm
• Missing perspective-client.wasm
• Unknown chart tag

AI-assisted analysis of perspective-dev/perspective@11c8238c0c (2026-09-09). Data as JSON: /api/errors/a8246030aea3cd48. Report an issue: GitHub.

Appendix: source

Thrown at rust/perspective-js/src/ts/wasm/decompress.ts:17

// ┏━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┓
// ┃ ██████ ██████ ██████       █      █      █      █      █ █▄  ▀███ █       ┃
// ┃ ▄▄▄▄▄█ █▄▄▄▄▄ ▄▄▄▄▄█  ▀▀▀▀▀█▀▀▀▀▀ █ ▀▀▀▀▀█ ████████▌▐███ ███▄  ▀█ █ ▀▀▀▀▀ ┃
// ┃ █▀▀▀▀▀ █▀▀▀▀▀ █▀██▀▀ ▄▄▄▄▄ █ ▄▄▄▄▄█ ▄▄▄▄▄█ ████████▌▐███ █████▄   █ ▄▄▄▄▄ ┃
// ┃ █      ██████ █  ▀█▄       █ ██████      █      ███▌▐███ ███████▄ █       ┃
// ┣━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┫
// ┃ Copyright (c) 2017, the Perspective Authors.                              ┃
// ┃ ╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌╌ ┃
// ┃ This file is part of the Perspective library, distributed under the terms ┃
// ┃ of the [Apache License 2.0](https://www.apache.org/licenses/LICENSE-2.0). ┃
// ┗━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━┛

// @ts-ignore
import { extract } from "pro_self_extracting_wasm";

if (typeof WebAssembly === "undefined") {
    throw new Error("WebAssembly not supported.");
}

interface Module extends WebAssembly.Exports {
    size(): number;
    offset(): number;
    memory: WebAssembly.Memory;
}

// Perform a silly dance to deal with the different ways webpack and esbuild
// load binary, as this may either be an `ArrayBuffer` or `URL` depending
// on whether `inline` option was specified to `perspective-esbuild-plugin`.
async function compile(
    buffer: ArrayBuffer | Response | WebAssembly.Module | WebAssembly.Exports,
): Promise<Module> {
    if (buffer instanceof Response) {
        return (await WebAssembly.instantiateStreaming(buffer)).instance
            .exports as Module;
    } else if (buffer instanceof WebAssembly.Module) {

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