diff --git a/.github/workflows/python-package.yml b/.github/workflows/python-package.yml
new file mode 100644
index 0000000..00a56bf
--- /dev/null
+++ b/.github/workflows/python-package.yml
@@ -0,0 +1,42 @@
+# This workflow will install Python dependencies, run tests and lint with a variety of Python versions
+# For more information see: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-python
+
+name: Python package
+
+on:
+  push:
+    branches: [ "master" ]
+  pull_request:
+    branches: [ "master" ]
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+    strategy:
+      fail-fast: false
+      matrix:
+        python-version: ["3.9", "3.10", "3.11"]
+
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v3
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        python -m pip install --upgrade pip
+        python -m pip install flake8 pytest
+        python -m pip install numpy scipy periodictable
+        python setup.py install
+        if [ -f requirements.txt ]; then pip install -r requirements.txt; fi
+    - 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
diff --git a/README.md b/README.md
index 1dccb0a..817bc77 100644
--- a/README.md
+++ b/README.md
@@ -42,9 +42,9 @@ For more examples, take a look at the `examples` folder.
   * Using PhreeqPython on Windows requires installing [Visual C++ Redistributable 2015](https://www.microsoft.com/en-us/download/details.aspx?id=48145)
 
 ## Unit Tests
-| **Mac/Linux** | **Windows** | **Coverage** |
-|---|---|---|
-| [![Build Status](https://travis-ci.com/Vitens/phreeqpython.svg?branch=master)](https://travis-ci.com/Vitens/phreeqpython) | [![Build status](https://ci.appveyor.com/api/projects/status/lr1jwspxdkgo85bv?svg=true)](https://ci.appveyor.com/project/abelheinsbroek/phreeqpython) | [![codecov](https://codecov.io/gh/Vitens/phreeqpython/branch/master/graph/badge.svg)](https://codecov.io/gh/Vitens/phreeqpython) |
+| **Mac/Linux** and **Windows** | **Coverage** |
+|---|---|
+| [![Python package](https://github.com/DocMT/phreeqpython/actions/workflows/python-package.yml/badge.svg)](https://github.com/DocMT/phreeqpython/actions/workflows/python-package.yml)| [![codecov](https://codecov.io/gh/Vitens/phreeqpython/branch/master/graph/badge.svg)](https://codecov.io/gh/Vitens/phreeqpython) |
 
 
 ## Acknowledgements
diff --git a/appveyor.yml b/appveyor.yml
index 5b984c1..11438cc 100644
--- a/appveyor.yml
+++ b/appveyor.yml
@@ -1,14 +1,15 @@
 build: false
 
 environment:
-    matrix:
-        - PYTHON: "C:\\Python36-x64"
-          PYTHON_VERSION: "3.9.1"
-          PYTHON_ARCH: "64"
+  matrix:
+    - PYTHON: "C:\\Python38-x64"
 init:
-  - "ECHO %PYTHON% %PYTHON_VERSION% %PYTHON_ARCH%"
+  - "ECHO %PYTHON%"
 
 install:
+  - "%PYTHON%/python.exe -m pip install --upgrade pip"
+  - "%PYTHON%/python.exe -m pip install pytest"
+  - "%PYTHON%/python.exe -m pip install numpy"
   - "%PYTHON%/python.exe -m pip install scipy"
   - "%PYTHON%/python.exe -m pip install periodictable"
   - "%PYTHON%/python.exe -m pip install nose"
diff --git a/phreeqpython/viphreeqc.py b/phreeqpython/viphreeqc.py
index ac913ac..6ae5499 100644
--- a/phreeqpython/viphreeqc.py
+++ b/phreeqpython/viphreeqc.py
@@ -15,7 +15,7 @@ def bytes(str_, encoding): #pylint: disable-msg=W0613
         """Compatibilty function for Python 3.
         """
         return str_
-    range = xrange #pylint: disable-msg=C0103
+    range = xrange #pylint: disable-msg=C0103 # noqa: F821
     #pylint: enable-msg=W0622
 
 
@@ -44,6 +44,8 @@ def __init__(self, dll_path=None):
                 dll_name = './lib/viphreeqc.so'
             elif sys.platform == 'darwin':
                 dll_name = './lib/viphreeqc.dylib'
+            elif 'emscripten' in sys.platform:
+                dll_name = './lib/viphreeqcwasm.so'
             else:
                 msg = 'Platform %s is not supported.' % sys.platform
                 raise NotImplementedError(msg)
diff --git a/setup.py b/setup.py
index 80fbe6b..6f15bdb 100644
--- a/setup.py
+++ b/setup.py
@@ -1,4 +1,4 @@
-from setuptools import setup
+from setuptools import setup, find_packages
 import os
 import sys
 import zipfile
@@ -11,8 +11,8 @@
       author='Abel Heinsbroek',
       author_email='abel.heinsbroek@vitens.nl',
       license='Apache Licence 2.0',
-      packages=['phreeqpython'],
+      packages=['phreeqpython', 'phreeqpython.lib', 'phreeqpython.database'],
       include_package_data=True,
       zip_safe=False,
-      install_requires=['periodictable']
+      install_requires=['periodictable','numpy','scipy']
       )
diff --git a/tests/test_phreeqpython.py b/tests/test_phreeqpython.py
index ae116c7..ddf864c 100644
--- a/tests/test_phreeqpython.py
+++ b/tests/test_phreeqpython.py
@@ -1,4 +1,4 @@
-from phreeqpython import PhreeqPython, Solution
+from phreeqpython import PhreeqPython, Solution, utility
 from pathlib import Path
 import pytest
 
@@ -39,7 +39,7 @@ def test01_basiscs(self):
         assert round(sol.species_activities['Ca+2'], 5) == 0.00054
 
         # test add_solution_simple as milligrams
-        sol2 = self.pp.add_solution_simple({'Ca': 40.078, 'Na': 22.99, 'MgSO4': 120.37}, units='mg')
+        sol2 = self.pp.add_solution_simple({'Ca': 40.078, 'Na': 22.99, 'MgSO4': utility.convert_units('MgSO4', 1, 'mmol', 'mg')}, units='mg')
         # test conversion from mg to mmol
         assert round(sol2.total("Ca", 'mmol'), 4) == 1
         # test amount in mg
@@ -57,7 +57,7 @@ def test02_solution_functions(self):
         assert round(sol.total('Cl'), 2) == 3.5
         assert round(sol.total('Mg'), 2) == 1
         # change solution in mgs (add and subtract)
-        sol.change({'Na': 11.495, 'MgCl2': -95.211}, 'mg')        
+        sol.change({'Na': 11.495, 'MgCl2': -utility.convert_units('MgCl2', 1, 'mmol', 'mg')}, 'mg')        
         assert round(sol.total('Cl'), 2) == 1.5
         assert round(sol.total('Mg'), 2) == 0
 
diff --git a/tests/test_utility.py b/tests/test_utility.py
index 75008ee..5f31db0 100644
--- a/tests/test_utility.py
+++ b/tests/test_utility.py
@@ -12,7 +12,7 @@ def test_convert_units(self):
         ) == 39997.0
         assert round(
             convert_units('NaOH', 1, from_units='mol', to_units='ug'), 0
-        ) == 39997110.0
+        ) == 39996769.0
 
         assert round(
             convert_units('NaOH', 1, from_units='mmol', to_units='mol'), 4