diff --git a/__tests__/02_observable_spec.tsx b/__tests__/02_observable_spec.tsx
new file mode 100644
index 0000000..6567c4c
--- /dev/null
+++ b/__tests__/02_observable_spec.tsx
@@ -0,0 +1,58 @@
+// See: https://github.com/pmndrs/jotai/discussions/2007
+import React, { Suspense, StrictMode } from 'react';
+import { useAtomValue } from 'jotai/react';
+import { atomWithObservable } from 'jotai/vanilla/utils';
+import { Subject, map } from 'rxjs';
+import { act, fireEvent, render } from '@testing-library/react';
+import { usePrepareAtoms } from '../src/index';
+
+describe('usePrepareAtoms w/ useObservable spec', () => {
+  it('writable count state without initial value and rxjs chain', async () => {
+    const single$ = new Subject<number>();
+    const double$ = single$.pipe(map((n) => n * 2));
+    const singleAtom = atomWithObservable(() => single$);
+    const doubleAtom = atomWithObservable(() => double$);
+
+    const CounterValue = () => {
+      const single = useAtomValue(singleAtom);
+      const double = useAtomValue(doubleAtom);
+
+      return (
+        <>
+          single: {single}, double: {double}
+        </>
+      );
+    };
+
+    const CounterButton = () => {
+      return (
+        <button type="button" onClick={() => single$.next(2)}>
+          button
+        </button>
+      );
+    };
+
+    const Prepare = () => {
+      usePrepareAtoms([singleAtom, doubleAtom]);
+      return null;
+    };
+
+    const { findByText, getByText } = render(
+      <StrictMode>
+        <Prepare />
+        <Suspense fallback="loading">
+          <CounterValue />
+        </Suspense>
+        <CounterButton />
+      </StrictMode>,
+    );
+
+    await findByText('loading');
+
+    fireEvent.click(getByText('button'));
+    await findByText('single: 2, double: 4');
+
+    act(() => single$.next(3));
+    await findByText('single: 3, double: 6');
+  });
+});
diff --git a/package.json b/package.json
index fe82314..3742602 100644
--- a/package.json
+++ b/package.json
@@ -70,6 +70,7 @@
     "prettier": "^2.8.3",
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
+    "rxjs": "^7.8.1",
     "ts-jest": "^29.0.5",
     "ts-loader": "^9.4.2",
     "typescript": "^4.9.5",
diff --git a/yarn.lock b/yarn.lock
index 93a9dab..5231ed3 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -6694,6 +6694,13 @@ run-parallel@^1.1.9:
   dependencies:
     queue-microtask "^1.2.2"
 
+rxjs@^7.8.1:
+  version "7.8.1"
+  resolved "https://registry.yarnpkg.com/rxjs/-/rxjs-7.8.1.tgz#6f6f3d99ea8044291efd92e7c7fcf562c4057543"
+  integrity sha512-AA3TVj+0A2iuIoQkWEK/tqFjBq2j+6PO6Y0zJcvzLAFhEFIO3HL0vls9hWLncZbAAbK0mar7oZ4V079I/qPMxg==
+  dependencies:
+    tslib "^2.1.0"
+
 sade@^1.7.4:
   version "1.8.1"
   resolved "https://registry.yarnpkg.com/sade/-/sade-1.8.1.tgz#0a78e81d658d394887be57d2a409bf703a3b2701"
@@ -7355,6 +7362,11 @@ tslib@^2.0.3, tslib@^2.4.0:
   resolved "https://registry.yarnpkg.com/tslib/-/tslib-2.5.0.tgz#42bfed86f5787aeb41d031866c8f402429e0fddf"
   integrity sha512-336iVw3rtn2BUK7ORdIAHTyxHGRIHVReokCR3XjbckJMK7ms8FysBfhLR8IXnAgy7T0PTPNBWKiH514FOW/WSg==
 
+tslib@^2.1.0:
+  version "2.6.0"
+  resolved "https://registry.yarnpkg.com/tslib/-/tslib-2.6.0.tgz#b295854684dbda164e181d259a22cd779dcd7bc3"
+  integrity sha512-7At1WUettjcSRHXCyYtTselblcHl9PJFFVKiCAy/bY97+BPZXSQ2wbq0P9s8tK2G7dFQfNnlJnPAiArVBVBsfA==
+
 tsutils@^3.21.0:
   version "3.21.0"
   resolved "https://registry.yarnpkg.com/tsutils/-/tsutils-3.21.0.tgz#b48717d394cea6c1e096983eed58e9d61715b623"