diff --git a/test/async.browser.js b/test/async.browser.js
index bc1417546..de63b16c0 100644
--- a/test/async.browser.js
+++ b/test/async.browser.js
@@ -130,98 +130,100 @@ export async function asyncBrowserTest(_fixtures) {
       await componentCleanup();
     });
 
-    test("Transpile async (browser, JSPI)", async () => {
-      const componentName = "async-call";
-      const {
-        instance,
-        cleanup: componentCleanup,
-        outputDir,
-      } = await setupAsyncTest({
-        asyncMode: "jspi",
-        component: {
-          name: "async_call",
-          path: resolve("test/fixtures/components/async_call.component.wasm"),
-          imports: {
-            "something:test/test-interface": {
-              callAsync: async () => "called async",
-              callSync: () => "called sync",
+    if (typeof WebAssembly?.Suspending === "function") {
+      test("Transpile async (browser, JSPI)", async () => {
+        const componentName = "async-call";
+        const {
+          instance,
+          cleanup: componentCleanup,
+          outputDir,
+        } = await setupAsyncTest({
+          asyncMode: "jspi",
+          component: {
+            name: "async_call",
+            path: resolve("test/fixtures/components/async_call.component.wasm"),
+            imports: {
+              "something:test/test-interface": {
+                callAsync: async () => "called async",
+                callSync: () => "called sync",
+              },
             },
           },
-        },
-        jco: {
-          transpile: {
-            extraArgs: {
-              asyncImports: ["something:test/test-interface#call-async"],
-              asyncExports: ["run-async"],
+          jco: {
+            transpile: {
+              extraArgs: {
+                asyncImports: ["something:test/test-interface#call-async"],
+                asyncExports: ["run-async"],
+              },
             },
           },
-        },
-      });
-      const moduleName = componentName.toLowerCase().replaceAll("-", "_");
-      const moduleRelPath = `${moduleName}/${moduleName}.js`;
-
-      strictEqual(
-        instance.runSync instanceof AsyncFunction,
-        false,
-        "runSync() should be a sync function",
-      );
-      strictEqual(
-        instance.runAsync instanceof AsyncFunction,
-        true,
-        "runAsync() should be an async function",
-      );
-
-      // Start a test web server
-      const {
-        server,
-        serverPort,
-        cleanup: webServerCleanup,
-      } = await startTestWebServer({
-        routes: [
-          // NOTE: the goal here is to serve relative paths via the browser hash
-          //
-          // (1) browser visits test page (served by test web server)
-          // (2) browser requests component itself by looking at URL hash fragment
-          //     (i.e. "#transpiled:async_call/async_call.js" -> , "/transpiled/async_call/async_call.js")
-          //     (i.e. "/transpiled/async_call/async_call.js" -> file read of /tmp/xxxxxx/async_call/async_call.js)
-          {
-            urlPrefix: "/transpiled/",
-            basePathURL: pathToFileURL(`${outputDir}/`),
-          },
-          // Serve all other files (ex. the initial HTML for the page)
-          { basePathURL: import.meta.url },
-        ],
-      });
-
-      // Start a browser to visit the test server
-      const browser = await puppeteer.launch({
-        args: [
-          "--enable-experimental-webassembly-jspi",
-          "--flag-switches-begin",
-          "--enable-features=WebAssemblyExperimentalJSPI",
-          "--flag-switches-end",
-        ],
-      });
-
-      // Load the test page in the browser, which will trigger tests against
-      // the component and/or related browser polyfills
-      const {
-        page,
-        output: { json },
-      } = await loadTestPage({
-        browser,
-        serverPort,
-        path: "fixtures/browser/test-pages/something__test.async.html",
-        hash: `transpiled:${moduleRelPath}`,
+        });
+        const moduleName = componentName.toLowerCase().replaceAll("-", "_");
+        const moduleRelPath = `${moduleName}/${moduleName}.js`;
+
+        strictEqual(
+          instance.runSync instanceof AsyncFunction,
+          false,
+          "runSync() should be a sync function",
+        );
+        strictEqual(
+          instance.runAsync instanceof AsyncFunction,
+          true,
+          "runAsync() should be an async function",
+        );
+
+        // Start a test web server
+        const {
+          server,
+          serverPort,
+          cleanup: webServerCleanup,
+        } = await startTestWebServer({
+          routes: [
+            // NOTE: the goal here is to serve relative paths via the browser hash
+            //
+            // (1) browser visits test page (served by test web server)
+            // (2) browser requests component itself by looking at URL hash fragment
+            //     (i.e. "#transpiled:async_call/async_call.js" -> , "/transpiled/async_call/async_call.js")
+            //     (i.e. "/transpiled/async_call/async_call.js" -> file read of /tmp/xxxxxx/async_call/async_call.js)
+            {
+              urlPrefix: "/transpiled/",
+              basePathURL: pathToFileURL(`${outputDir}/`),
+            },
+            // Serve all other files (ex. the initial HTML for the page)
+            { basePathURL: import.meta.url },
+          ],
+        });
+
+        // Start a browser to visit the test server
+        const browser = await puppeteer.launch({
+          args: [
+            "--enable-experimental-webassembly-jspi",
+            "--flag-switches-begin",
+            "--enable-features=WebAssemblyExperimentalJSPI",
+            "--flag-switches-end",
+          ],
+        });
+
+        // Load the test page in the browser, which will trigger tests against
+        // the component and/or related browser polyfills
+        const {
+          page,
+          output: { json },
+        } = await loadTestPage({
+          browser,
+          serverPort,
+          path: "fixtures/browser/test-pages/something__test.async.html",
+          hash: `transpiled:${moduleRelPath}`,
+        });
+
+        // Check the output expected to be returned from handle of the
+        // guest export (this depends on the component)
+        deepStrictEqual(json, { responseText: "callAsync" });
+
+        await browser.close();
+        await webServerCleanup();
+        await componentCleanup();
       });
-
-      // Check the output expected to be returned from handle of the
-      // guest export (this depends on the component)
-      deepStrictEqual(json, { responseText: "callAsync" });
-
-      await browser.close();
-      await webServerCleanup();
-      await componentCleanup();
-    });
+    }
   });
 }
diff --git a/test/async.js b/test/async.js
index d888c6bf5..0742f69fc 100644
--- a/test/async.js
+++ b/test/async.js
@@ -68,41 +68,43 @@ export async function asyncTest(_fixtures) {
       ok(source.toString().includes("export { test"));
     });
 
-    test("Transpile async (NodeJS, JSPI)", async () => {
-      const { instance, cleanup, component } = await setupAsyncTest({
-        asyncMode: "jspi",
-        component: {
-          name: "async_call",
-          path: resolve("test/fixtures/components/async_call.component.wasm"),
-          imports: {
-            'something:test/test-interface': {
-              callAsync: async () => "called async",
-              callSync: () => "called sync",
+    if (typeof WebAssembly?.Suspending === "function") {
+      test("Transpile async (NodeJS, JSPI)", async () => {
+        const { instance, cleanup, component } = await setupAsyncTest({
+          asyncMode: "jspi",
+          component: {
+            name: "async_call",
+            path: resolve("test/fixtures/components/async_call.component.wasm"),
+            imports: {
+              'something:test/test-interface': {
+                callAsync: async () => "called async",
+                callSync: () => "called sync",
+              },
             },
           },
-        },
-        jco: {
-          transpile: {
-            extraArgs: {
-              asyncImports: [
-                "something:test/test-interface#call-async",
-              ],
-              asyncExports: [
-                "run-async",
-              ],
+          jco: {
+            transpile: {
+              extraArgs: {
+                asyncImports: [
+                  "something:test/test-interface#call-async",
+                ],
+                asyncExports: [
+                  "run-async",
+                ],
+              },
             },
           },
-        },
-      });
+        });
 
-      strictEqual(instance.runSync instanceof AsyncFunction, false, "runSync() should be a sync function");
-      strictEqual(instance.runAsync instanceof AsyncFunction, true, "runAsync() should be an async function");
+        strictEqual(instance.runSync instanceof AsyncFunction, false, "runSync() should be a sync function");
+        strictEqual(instance.runAsync instanceof AsyncFunction, true, "runAsync() should be an async function");
 
-      strictEqual(instance.runSync(), "called sync");
-      strictEqual(await instance.runAsync(), "called async");
+        strictEqual(instance.runSync(), "called sync");
+        strictEqual(await instance.runAsync(), "called async");
 
-      await cleanup();
-    });
+        await cleanup();
+      });
+    }
 
     test("Transpile async (NodeJS, Asyncify)", async () => {
       const { instance, cleanup } = await setupAsyncTest({