diff --git a/npm/packages/rvf-wasm/package.json b/npm/packages/rvf-wasm/package.json
index 9cc2dcd41..cc17ab798 100644
--- a/npm/packages/rvf-wasm/package.json
+++ b/npm/packages/rvf-wasm/package.json
@@ -1,22 +1,23 @@
 {
   "name": "@ruvector/rvf-wasm",
-  "version": "0.1.5",
+  "version": "0.1.7",
   "description": "RuVector Format WASM microkernel for browser and edge vector operations",
-  "main": "pkg/rvf_wasm.js",
+  "type": "module",
+  "main": "pkg/rvf_wasm.mjs",
   "types": "pkg/rvf_wasm.d.ts",
   "exports": {
     ".": {
       "types": "./pkg/rvf_wasm.d.ts",
-      "import": "./pkg/rvf_wasm.mjs",
-      "require": "./pkg/rvf_wasm.js",
-      "default": "./pkg/rvf_wasm.js"
+      "default": "./pkg/rvf_wasm.mjs"
     }
   },
   "files": [
     "pkg/"
   ],
   "scripts": {
-    "build": "cargo build --release --target wasm32-unknown-unknown --manifest-path ../../crates/rvf/rvf-wasm/Cargo.toml && wasm-opt -Oz ../../crates/rvf/target/wasm32-unknown-unknown/release/rvf_wasm.wasm -o pkg/rvf_wasm_bg.wasm"
+    "build": "cargo build --release --target wasm32-unknown-unknown --manifest-path ../../crates/rvf/rvf-wasm/Cargo.toml && wasm-opt -Oz ../../crates/rvf/target/wasm32-unknown-unknown/release/rvf_wasm.wasm -o pkg/rvf_wasm_bg.wasm",
+    "test": "node tests/smoke.mjs",
+    "prepublishOnly": "node tests/smoke.mjs"
   },
   "license": "MIT",
   "repository": {
diff --git a/npm/packages/rvf-wasm/tests/smoke.mjs b/npm/packages/rvf-wasm/tests/smoke.mjs
new file mode 100644
index 000000000..811c5b241
--- /dev/null
+++ b/npm/packages/rvf-wasm/tests/smoke.mjs
@@ -0,0 +1,39 @@
+// Smoke test: regression guard for issue #415.
+// Verifies that @ruvector/rvf-wasm can be loaded as ESM without
+// `SyntaxError: Cannot use 'import.meta' outside a module` and that
+// init() returns a usable WASM exports object.
+
+import { fileURLToPath } from 'node:url';
+import { dirname, join } from 'node:path';
+
+const __dirname = dirname(fileURLToPath(import.meta.url));
+const pkgRoot = join(__dirname, '..');
+
+let failures = 0;
+function assert(cond, msg) {
+  if (!cond) {
+    console.error('FAIL:', msg);
+    failures++;
+  } else {
+    console.log('  ok:', msg);
+  }
+}
+
+// 1. ESM import via package.json `default` (the published surface).
+const mod = await import(join(pkgRoot, 'pkg/rvf_wasm.mjs'));
+assert(typeof mod.default === 'function', 'mjs default export is a function');
+
+// 2. Initialize and confirm we got real WASM exports back.
+const exports_ = await mod.default();
+assert(exports_ != null && typeof exports_ === 'object', 'init() returned exports object');
+assert(exports_.memory instanceof WebAssembly.Memory, 'exports.memory is WebAssembly.Memory');
+
+// 3. Idempotent re-init returns the cached instance.
+const exports2 = await mod.default();
+assert(exports2 === exports_, 'init() is idempotent');
+
+if (failures > 0) {
+  console.error(`\n${failures} smoke check(s) failed`);
+  process.exit(1);
+}
+console.log('\nrvf-wasm smoke OK');