diff --git a/.github/workflows/tests.yaml b/.github/workflows/tests.yaml
new file mode 100644
index 0000000..99e9007
--- /dev/null
+++ b/.github/workflows/tests.yaml
@@ -0,0 +1,31 @@
+### Running pytest
+
+name: BrahMap testing
+on:
+  push:
+    branches:
+      - main
+jobs:
+  build:
+    runs-on: ${{ matrix.os }}
+    strategy:
+      fail-fast: false
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        python-version: ["3.9", "3.10", "3.11", "3.12"]
+
+    steps:
+      - uses: actions/checkout@v4
+        with:
+          submodules: true
+      - name: Set up Python ${{ matrix.python-version }}
+        uses: actions/setup-python@v4
+        with:
+          python-version: ${{ matrix.python-version }}
+      - name: Install BrahMap
+        run: |
+          python -m pip install --upgrade pip
+          python -m pip install .
+      - name: Test BrahMap with pytest
+        run: |
+          pytest
diff --git a/MANIFEST.in b/MANIFEST.in
index eff8add..27bba1b 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1 +1,5 @@
 recursive-include extern *
+recursive-include tests *
+global-exclude */__pycache__/*
+global-exclude *.pyc
+global-exclude */.pytest_cache/*
diff --git a/README.md b/README.md
index 698a5ec..93ce25f 100644
--- a/README.md
+++ b/README.md
@@ -23,7 +23,7 @@ for a completer reference to `BrahMap` API.
 
 ```shell
 # Clone the repository
-git clone https://github.com/anand-avinash/BrahMap.git
+git clone --recursive https://github.com/anand-avinash/BrahMap.git
 
 cd BrahMap
 
diff --git a/brahmap/src/__init__.py b/brahmap/src/__init__.py
new file mode 100644
index 0000000..e69de29
diff --git a/brahmap/utilities/__init__.py b/brahmap/utilities/__init__.py
index e81c9a6..16e64d8 100644
--- a/brahmap/utilities/__init__.py
+++ b/brahmap/utilities/__init__.py
@@ -19,8 +19,14 @@
 )
 
 from .process_ces import ProcessTimeSamples
-from .lbsim_interface import lbs_process_timesamples
 
+from importlib.util import find_spec
+
+# suggestion taken from: <https://docs.astral.sh/ruff/rules/unused-import/>
+if find_spec("litebird_sim") is not None:
+    import_str = "lbs_process_timesamples"
+else:
+    import_str = None
 
 __all__ = [
     "is_sorted",
@@ -36,5 +42,5 @@
     "subscan_resize",
     "system_setup",
     "ProcessTimeSamples",
-    "lbs_process_timesamples",
+    import_str,
 ]
diff --git a/docs/index.md b/docs/index.md
index c355c23..8e4eedb 100644
--- a/docs/index.md
+++ b/docs/index.md
@@ -23,7 +23,7 @@ for a completer reference to `BrahMap` API.
 
 ```shell
 # Clone the repository
-git clone https://github.com/anand-avinash/BrahMap.git
+git clone --recursive https://github.com/anand-avinash/BrahMap.git
 
 cd BrahMap
 
diff --git a/pyproject.toml b/pyproject.toml
index cb506e5..e06f6eb 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -16,6 +16,7 @@ requires-python = ">=3.9,<3.13"
 dependencies = [
     "numpy",
     "scipy",
+    "healpy",
     "krypy",
     "ruff",
     "pre-commit",
@@ -32,8 +33,10 @@ Documentation = "https://anand-avinash.github.io/BrahMap/"
 Issues = "https://github.com/anand-avinash/BrahMap/issues"
 # Changelog = 
 
-[tool.setuptools]
-packages = ["brahmap"]
+[tool.setuptools.packages.find]
+where = ["."]
+include = ["brahmap*"]
+namespaces = false
 
 [tool.pytest.ini_options]
 norecursedirs = ["extern"]
diff --git a/brahmap/tests/helper_BlkDiagPrecondLO.py b/tests/helper_BlkDiagPrecondLO.py
similarity index 100%
rename from brahmap/tests/helper_BlkDiagPrecondLO.py
rename to tests/helper_BlkDiagPrecondLO.py
diff --git a/brahmap/tests/helper_SparseLO.py b/tests/helper_SparseLO.py
similarity index 100%
rename from brahmap/tests/helper_SparseLO.py
rename to tests/helper_SparseLO.py
diff --git a/brahmap/tests/helper_initweigths.py b/tests/helper_initweigths.py
similarity index 100%
rename from brahmap/tests/helper_initweigths.py
rename to tests/helper_initweigths.py
diff --git a/brahmap/tests/helper_repixelize.py b/tests/helper_repixelize.py
similarity index 100%
rename from brahmap/tests/helper_repixelize.py
rename to tests/helper_repixelize.py
diff --git a/brahmap/tests/test_BlkDiagPrecondLO_tools_cpp.py b/tests/test_BlkDiagPrecondLO_tools_cpp.py
similarity index 100%
rename from brahmap/tests/test_BlkDiagPrecondLO_tools_cpp.py
rename to tests/test_BlkDiagPrecondLO_tools_cpp.py
diff --git a/brahmap/tests/test_SparseLO_tools_cpp.py b/tests/test_SparseLO_tools_cpp.py
similarity index 100%
rename from brahmap/tests/test_SparseLO_tools_cpp.py
rename to tests/test_SparseLO_tools_cpp.py
diff --git a/brahmap/tests/test_process_samples_cpp.py b/tests/test_process_samples_cpp.py
similarity index 100%
rename from brahmap/tests/test_process_samples_cpp.py
rename to tests/test_process_samples_cpp.py
diff --git a/brahmap/tests/test_repixelize_cpp.py b/tests/test_repixelize_cpp.py
similarity index 100%
rename from brahmap/tests/test_repixelize_cpp.py
rename to tests/test_repixelize_cpp.py