diff --git a/pyscript.core/esm/worker/_template.js b/pyscript.core/esm/worker/_template.js
index 1f55c412..990f3d6c 100644
--- a/pyscript.core/esm/worker/_template.js
+++ b/pyscript.core/esm/worker/_template.js
@@ -9,6 +9,19 @@ import coincident from "coincident/structured";
 import { registry } from "../runtimes.js";
 import { getRuntime, getRuntimeID } from "../loader.js";
 
+// bails out out of the box with a native/meaningful error
+// in case the SharedArrayBuffer is not available
+try {
+    new SharedArrayBuffer(4);
+} catch (_) {
+    throw new Error(
+        [
+            "Unable to use SharedArrayBuffer due insecure environment.",
+            "Please read requirements in MDN: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/SharedArrayBuffer#security_requirements",
+        ].join("\n"),
+    );
+}
+
 let engine, run, runtimeEvent;
 const add = (type, fn) => {
     addEventListener(
diff --git a/pyscript.core/package.json b/pyscript.core/package.json
index 5666aa7a..9d197a27 100644
--- a/pyscript.core/package.json
+++ b/pyscript.core/package.json
@@ -50,6 +50,6 @@
         "coincident": "^0.2.3"
     },
     "worker": {
-        "blob": "sha256-m8uF2bNB691FtVIpuDfAT/avUolqZRQwO9tD3r88+6A="
+        "blob": "sha256-LhH/RqqHJJNjYkIoMjALOt1xdneBHAyy+jgMKO07Mx0="
     }
 }