diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
index bda4276..221ee73 100644
--- a/.github/workflows/build.yml
+++ b/.github/workflows/build.yml
@@ -21,7 +21,11 @@ jobs:
       matrix:
         include:
           - os: "ubuntu-latest"
-            python-version: '3.8'  # first supported
+            python-version: '3.9'  # first supported
+          - os: "windows-latest"
+            python-version: '3.9'  # first supported
+          - os: "macos-latest"
+            python-version: '3.9'  # first supported
           - os: "ubuntu-latest"
             python-version: '3.12'  # latest supported
           - os: "windows-latest"
diff --git a/README.rst b/README.rst
index 84118a6..b0e981b 100644
--- a/README.rst
+++ b/README.rst
@@ -18,12 +18,14 @@ ismn
 
 Readers for data from the International Soil Moisture Network (ISMN) https://ismn.earth.
 
-This package is installable through pip:
+This package is installable through pip (verified for ``python>=3.9``)
 
 .. code::
 
     pip install ismn
 
+This should also install all dependencies on Window, Linux or MacOS.
+
 Quickstart
 ----------
 Initialise an `ISMN_Interface` by passing the path to your downloaded data.
@@ -97,7 +99,7 @@ are only needed when creating data visualisations. They can be installed separat
 
     conda install -c conda-forge matplotlib cartopy
 
- or ``pip install ismn[plot]`` for most operating systems if you already have `geos <https://libgeos.org/>`_ installed.
+or ``pip install ismn[plot]`` for most operating systems if you already have `geos <https://libgeos.org/>`_ installed.
 
 If you want to convert ISMN data into xarray objects, please install `xarray <https://github.com/pydata/xarray>`_ and
 `dask <https://github.com/dask/dask>`_ via