diff --git a/.github/workflows/build.yml b/.github/workflows/build.yml
new file mode 100644
index 0000000..d7445f2
--- /dev/null
+++ b/.github/workflows/build.yml
@@ -0,0 +1,16 @@
+name: Build
+
+on: [push, pull_request]
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v3
+    - uses: actions/setup-python@v4
+    - name: Setup environment
+      run: source tools/ci.sh && ci_build_packages_setup
+    - name: Check manifest files
+      run: source tools/ci.sh && ci_build_packages_check_manifest
+    - name: Compile package index
+      run: source tools/ci.sh && ci_build_packages_compile_index
diff --git a/.github/workflows/code-formatting.yml b/.github/workflows/code-formatting.yml
index 88c23ee..6c7c744 100644
--- a/.github/workflows/code-formatting.yml
+++ b/.github/workflows/code-formatting.yml
@@ -7,8 +7,10 @@ jobs:
   build:
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v3
+    - uses: actions/checkout@v4
     - uses: actions/setup-python@v4
+      with:
+        python-version: '3.11'
     - name: Install packages
       run: source tools/ci.sh && ci_code_formatting_setup
     - name: Run code formatting
diff --git a/.github/workflows/pylint.yml b/.github/workflows/pylint.yml
index 5f71c3f..44188a0 100644
--- a/.github/workflows/pylint.yml
+++ b/.github/workflows/pylint.yml
@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        python-version: ["3.8", "3.9", "3.10"]
+        python-version: ["3.8"]
     steps:
     - uses: actions/checkout@v3
     - name: Set up Python ${{ matrix.python-version }}
@@ -19,7 +19,14 @@ jobs:
     - name: Install dependencies
       run: |
         python -m pip install --upgrade pip
+        pip -v install micropython-stubber
+        pip -v install -U  micropython-esp32-stubs
         pip install pylint
+        pwd
+        ls -a
+        ls -a /
+        find /opt -name micropython-*
+        find /usr -name micropython-*
     - name: Analysing the code with pylint
       run: |
         pylint $(git ls-files 'adc1_cal.py')
diff --git a/.pylintrc b/.pylintrc
new file mode 100644
index 0000000..e2b5a0a
--- /dev/null
+++ b/.pylintrc
@@ -0,0 +1,7 @@
+[MASTER]
+# Loaded Stubs:  esp32-micropython-1.11.0 
+init-hook='import sys;sys.path[1:1] = ["src/lib", "all-stubs/cpython-core", "all-stubs/mpy_1_12/frozen/esp32/GENERIC", "all-stubs/esp32_1_13_0-103",]'
+
+disable = missing-docstring, line-too-long, trailing-newlines, broad-except, logging-format-interpolation, invalid-name, 
+        no-method-argument, assignment-from-no-return, too-many-function-args, unexpected-keyword-arg
+        # the 2nd  line deals with the limited information in the generated stubs.
diff --git a/README.md b/README.md
index a0538e4..404a00a 100644
--- a/README.md
+++ b/README.md
@@ -1,6 +1,5 @@
-[![formatting: lint](https://github.com/matthias-bs/MicroPython-ADC_Cal/actions/workflows/ci.yml/badge.svg)](https://github.com/matthias-bs/MicroPython-ADC_Cal/actions/workflows/ci.yml)
+[![formatting: lint](https://github.com/matthias-bs/MicroPython-ADC_Cal/actions/workflows/code-formatting.yml/badge.svg)](https://github.com/matthias-bs/MicroPython-ADC_Cal/actions/workflows/ci.yml)
 [![GitHub release](https://img.shields.io/github/release/matthias-bs/MicroPython-ADC_Cal?maxAge=3600)](https://github.com/matthias-bs/MicroPython-ADC_Cal/releases)
-[![License: GPLv3](https://img.shields.io/badge/license-GPLv3-green)](https://github.com/matthias-bs/MicroPython-ADC_Cal/blob/main/LICENSE)
 
 # MicroPython-ADC_Cal
 **MicroPython ESP32 library for calibrated on-chip ADC conversion**
diff --git a/adc1_cal.py b/adc1_cal.py
index 2529f7e..7fd8d41 100644
--- a/adc1_cal.py
+++ b/adc1_cal.py
@@ -1,4 +1,5 @@
 """MicroPython ESP32 ADC1 conversion using V_ref calibration value"""
+
 ###############################################################################
 # adc1_cal.py
 #
diff --git a/manifest.py b/manifest.py
new file mode 100644
index 0000000..ac61118
--- /dev/null
+++ b/manifest.py
@@ -0,0 +1,8 @@
+metadata(
+    version="1.0.1",
+    description="MicroPython ESP32 library for calibrated on-chip ADC conversion",
+    author="matthias-bs",
+    license="MIT",
+)
+
+module("adc1_cal.py", opt=3)
diff --git a/package.json b/package.json
new file mode 100644
index 0000000..3be72f2
--- /dev/null
+++ b/package.json
@@ -0,0 +1,7 @@
+{
+  "urls": [
+    ["adc1_cal.py", "github:matthias-bs/MicroPython-ADC_Cal/adc1_cal.py"]
+  ],
+  "version": "1.0.1",
+  "deps": []
+}
diff --git a/tools/README.txt b/tools/README.txt
new file mode 100644
index 0000000..bf5c291
--- /dev/null
+++ b/tools/README.txt
@@ -0,0 +1,8 @@
+"Black" is used for MicroPython code style checking:
+https://github.com/psf/black
+
+"uncrustify" is NOT used in this project, thus uncrustify.cfg wil not be used!
+
+ MicroPython-ADC_Cal/.github/workflows/code-formatting.yml calls ci.sh,
+ which in turn executes codeformat.py, which will execute black.py.
+ 
diff --git a/tools/ci.sh b/tools/ci.sh
index d0dafbc..d9e791d 100644
--- a/tools/ci.sh
+++ b/tools/ci.sh
@@ -27,6 +27,7 @@ function ci_build_packages_setup {
     # check the required programs run
     /tmp/micropython/mpy-cross/build/mpy-cross --version
     python3 /tmp/micropython/tools/manifestfile.py --help
+    /tmp/micropython/mpy-cross/build/mpy-cross adc1_cal.py
 }
 
 function ci_build_packages_check_manifest {
diff --git a/tools/codeformat.py b/tools/codeformat.py
index 47b12df..63c9c59 100644
--- a/tools/codeformat.py
+++ b/tools/codeformat.py
@@ -46,7 +46,6 @@
 TOP = os.path.abspath(os.path.join(os.path.dirname(__file__), ".."))
 
 UNCRUSTIFY_CFG = os.path.join(TOP, "tools/uncrustify.cfg")
-print("UNCRUSTIFY_CFG: ", UNCRUSTIFY_CFG)
 
 C_EXTS = (
     ".c",