diff --git a/.gitignore b/.gitignore
index 9f7550b..68bc17f 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,2 +1,160 @@
-__pycache__
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# poetry
+#   Similar to Pipfile.lock, it is generally recommended to include poetry.lock in version control.
+#   This is especially recommended for binary packages to ensure reproducibility, and is more
+#   commonly ignored for libraries.
+#   https://python-poetry.org/docs/basic-usage/#commit-your-poetrylock-file-to-version-control
+#poetry.lock
+
+# pdm
+#   Similar to Pipfile.lock, it is generally recommended to include pdm.lock in version control.
+#pdm.lock
+#   pdm stores project-wide configurations in .pdm.toml, but it is recommended to not include it
+#   in version control.
+#   https://pdm.fming.dev/#use-with-ide
+.pdm.toml
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow and github.com/pdm-project/pdm
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
 .venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
+
+# PyCharm
+#  JetBrains specific template is maintained in a separate JetBrains.gitignore that can
+#  be found at https://github.com/github/gitignore/blob/main/Global/JetBrains.gitignore
+#  and can be added to the global gitignore or merged into this file.  For a more nuclear
+#  option (not recommended) you can uncomment the following to ignore the entire idea folder.
+#.idea/
diff --git a/requirements.txt b/requirements.txt
index bdd037a..44bb4cd 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,3 +1,5 @@
 pandas
 numpy
-GitPython
\ No newline at end of file
+GitPython
+typer[all]
+calmap
\ No newline at end of file
diff --git a/setup.cfg b/setup.cfg
new file mode 100644
index 0000000..74ab847
--- /dev/null
+++ b/setup.cfg
@@ -0,0 +1,30 @@
+[metadata]
+name = gitstats
+version = attr: gitstats.__version__
+author = Samuel Ortion
+author_email = samuel+git@ortion.fr
+keywords = git, contributions
+license = GPLv3
+license_files = LICENSE
+long_description = file: README.md
+long_description_content_type = text/markdown
+classifiers =
+    Development Status :: 3 - Alpha
+    Intended Audience :: Developers
+    License :: OSI Approved :: GNU General Public License v3
+    Programming Language :: Python :: 3
+    Topic :: Scientific/Engineering :: Bio-Informatics
+
+[options]
+packages = find:
+package_dir =
+    =src
+python_require = >= 3.7 # What is the minimum version of python required?
+install_required = file: requirements.txt
+
+[options.entry_points]
+console_scripts =
+    git.stats=gitstats.__main__:main
+
+[options.packages.find]
+where = src
diff --git a/setup.py b/setup.py
new file mode 100644
index 0000000..229b2eb
--- /dev/null
+++ b/setup.py
@@ -0,0 +1,5 @@
+#!/usr/bin/env python3
+
+from setuptools import setup
+
+setup()
diff --git a/src/gitstats/__init__.py b/src/gitstats/__init__.py
new file mode 100644
index 0000000..a68927d
--- /dev/null
+++ b/src/gitstats/__init__.py
@@ -0,0 +1 @@
+__version__ = "0.1.0"
\ No newline at end of file
diff --git a/src/gitstats/__main__.py b/src/gitstats/__main__.py
new file mode 100644
index 0000000..fb3258a
--- /dev/null
+++ b/src/gitstats/__main__.py
@@ -0,0 +1,57 @@
+import logging
+from collections import defaultdict
+
+import typer
+from typing import Optional
+from git import Repo
+import matplotlib.pyplot as plt
+import pandas as pd
+
+from . import commits
+from . import plots
+
+app = typer.Typer()
+
+
+@app.command()
+def count(dir_name: str, year: int = 2023, author_name: str = None, output_csv: Optional[str] = None) -> pd.DataFrame:
+    # Count the number of commits each days for git repositories in the folder
+    commit_date_counter = defaultdict(int)
+    for repo_dir in commits.iter_repos(dir_name):
+        repo = Repo(repo_dir)
+        if repo.heads != []:
+            repo_commit_date_counter = commits.repo_daily_commits(repo, year, author_name)
+            for key, count in repo_commit_date_counter.items():
+                commit_date_counter[key] += 1
+    # Construct a pandas DataFrame with this data
+    df = pd.DataFrame({"date": commit_date_counter.keys(), "count": commit_date_counter.values()})
+    df["date"] = pd.to_datetime(df["date"])
+    
+    if output_csv is not None:
+        df.to_csv(output_csv, sep=";", index=False)
+    return df
+
+@app.command()
+def plot(input_csv: str, output_plot: Optional[str] = None):
+    df = pd.read_csv(input_csv, sep=";")
+    df["date"] = pd.to_datetime(df["date"])
+    plots.year_of_contributions(df)
+    plt.show()
+
+
+@app.command()
+def pipe(dir: str = ".", author: Optional[str] = None, year: Optional[int] = None, output_csv: Optional[str] = None, output_plot: Optional[str] = None):
+    df = count(dir_name=dir, year=year, author_name=author, output_csv=output_csv)
+    if output_csv:
+        df.to_csv(output_csv, sep=";")
+    plots.year_of_contributions(df)
+    if output_plot:
+        plt.savefig(output_plot)
+
+
+def main():
+    app()
+
+
+if __name__ == "__main__":
+    main()
\ No newline at end of file
diff --git a/src/gitstats/commits.py b/src/gitstats/commits.py
index e812192..02ede41 100644
--- a/src/gitstats/commits.py
+++ b/src/gitstats/commits.py
@@ -2,24 +2,56 @@
 Generate a CSV file with daily stats commit count from a set of repositories
 """
 
-from git import Repo
 import datetime
+import os
+import logging
+from collections import defaultdict
+from typing import Iterable, Optional
+
+from git import Repo
 
 REPO = "."
 
-repo = Repo(REPO)
+logger = logging.getLogger(__name__)
 
-def repo_daily_commits(repo: Repo, year: int):
+def wrapper(gen: Iterable, repo: Repo):
+    while True:
+        try:
+            yield next(gen)
+        except StopIteration:
+            break
+        except Exception as e:
+            logger.error(e)
+            logger.error(f"Occured in this repo: {repo.working_dir}")
+            logger.error("Will probably omit anterior commits")
+
+def repo_daily_commits(repo: Repo, year: Optional[int] = None, author_name: Optional[str] = None):
     """Count how many commit was performed for each days in the year"""
-    data = {}
-    for commit in repo.iter_commits(all=True):
-        timestamp = commit.authored_date
-        date = datetime.date.fromtimestamp(timestamp)
-        if int(date.year) != year:
-            continue
-        if date not in data:
-            data[date] = 0
-        data[date] += 1
+    if author_name is not None:
+        author_name = author_name.lower()
+    other_author_names: set = set()
+    data = defaultdict(int)
+    for commit in wrapper(repo.iter_commits(all=True), repo):
+        if author_name is not None:
+            commit_author: str = commit.author.name
+            if commit_author.lower() != author_name:
+                other_author_names.add(commit_author)
+        commit_timestamp: int = commit.authored_date
+        commit_date: datetime.date = datetime.date.fromtimestamp(
+            commit_timestamp)
+        if year is not None:
+            if commit_date.year != year:
+                continue
+        data[commit_date] += 1
+    if author_name is not None:
+        # Warn for all other author names
+        for other_author_name in other_author_names:
+            logger.info(f"Other commit author in this folder of repositories:\t{other_author_name}")
     return data
 
-print(repo_daily_commits(repo, 2023))
\ No newline at end of file
+def iter_repos(dir_name: str):
+    pys = []
+    for root, dirs, files in os.walk(dir_name):
+        for directory in dirs:
+            if directory == '.git':
+                yield os.path.join(root, directory)
diff --git a/src/gitstats/plots.py b/src/gitstats/plots.py
new file mode 100644
index 0000000..0cfdbfc
--- /dev/null
+++ b/src/gitstats/plots.py
@@ -0,0 +1,20 @@
+"""Plot contribution heatmap using calmap
+
+ref. https://builtin.com/data-science/github-contribution-plot"""
+
+import calmap
+import pandas as pd
+import matplotlib.pyplot as plt
+
+def year_of_contributions(df: pd.DataFrame):
+    events = pd.Series(df["count"], index=df["date"])
+    fig = plt.figure(figsize=(20,8))
+    ax = fig.add_subplot(111)
+    cax = calmap.yearplot(events,  # cmap='YlGn',
+        fillcolor='lightgrey',
+        daylabels="MTWTFSS",
+        dayticks=[0, 2, 4, 6],
+        linewidth=2,
+        ax=ax
+    )
+    # fig.colorbar(cax.get_children()[1], ax=cax, orientation='horizontal') # FIXME: this is ugly.
\ No newline at end of file
diff --git a/tmp.csv b/tmp.csv
new file mode 100644
index 0000000..5963c24
--- /dev/null
+++ b/tmp.csv
@@ -0,0 +1,198 @@
+;date;count
+0;2023-04-12;5
+1;2023-01-12;3
+2;2023-03-28;4
+3;2023-01-28;3
+4;2023-01-16;1
+5;2023-01-13;2
+6;2023-03-29;6
+7;2023-04-23;4
+8;2023-02-23;2
+9;2023-02-02;3
+10;2023-01-15;5
+11;2023-01-14;4
+12;2023-08-26;4
+13;2023-05-29;4
+14;2023-03-25;2
+15;2023-01-08;3
+16;2023-01-06;4
+17;2023-01-05;3
+18;2023-01-04;3
+19;2023-06-23;2
+20;2023-06-19;2
+21;2023-06-15;5
+22;2023-05-31;4
+23;2023-05-28;2
+24;2023-05-17;3
+25;2023-05-14;3
+26;2023-05-08;4
+27;2023-05-07;4
+28;2023-05-06;2
+29;2023-04-19;2
+30;2023-04-18;3
+31;2023-04-09;4
+32;2023-04-01;3
+33;2023-03-12;3
+34;2023-03-11;2
+35;2023-03-05;2
+36;2023-01-19;1
+37;2023-04-03;3
+38;2023-02-07;3
+39;2023-02-04;4
+40;2023-02-18;3
+41;2023-02-17;4
+42;2023-01-23;2
+43;2023-01-17;3
+44;2023-01-09;2
+45;2023-08-11;2
+46;2023-07-25;2
+47;2023-08-07;1
+48;2023-08-05;2
+49;2023-07-31;3
+50;2023-07-19;1
+51;2023-07-13;1
+52;2023-07-12;1
+53;2023-07-04;3
+54;2023-06-14;1
+55;2023-06-11;2
+56;2023-06-01;2
+57;2023-05-15;1
+58;2023-05-12;1
+59;2023-05-27;2
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