may I suggest a test and a bit of a clean-up

.github/workflows/python-app.yml

@@ -0,0 +1,36 @@
+# This workflow will install Python dependencies, run tests and lint with a single version of Python
+# For more information see: https://help.github.com/actions/language-and-framework-guides/using-python-with-github-actions
+
+name: Python application
+
+on:
+  push:
+    branches: [ master ]
+  pull_request:
+    branches: [ master ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python 3.8
+      uses: actions/setup-python@v2
+      with:
+        python-version: 3.8
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        pip install flake8 pytest
+        pip install .
+    - name: Lint with flake8
+      run: |
+        # stop the build if there are Python syntax errors or undefined names
+        flake8 . --count --select=E9,F63,F7,F82 --show-source --statistics
+        # exit-zero treats all errors as warnings. The GitHub editor is 127 chars wide
+        flake8 . --count --exit-zero --max-complexity=10 --max-line-length=127 --statistics
+    - name: Test with pytest
+      run: |
+        pytest

.gitignore

@@ -0,0 +1,4 @@
+build
+dist
+*.egg-info
+*.pyc

tests/test_example.py

@@ -0,0 +1,13 @@
+def test_array_of_int():
+    import json
+    import numpy as np
+    from numpyencoder import NumpyEncoder
+
+    numpy_data = np.array([np.int64(0), np.int32(1), 2, 3])
+    baseline_data = [0, 1, 2, 3]
+
+    j_np = json.dumps(numpy_data, sort_keys=True,
+                      separators=(', ', ': '), ensure_ascii=False,
+                      cls=NumpyEncoder)
+
+    assert json.dumps(baseline_data, sort_keys=True) == j_np