diff --git a/build_number_generator/__init__.py b/build_number_generator/__init__.py
new file mode 100644
index 0000000..f570fa4
--- /dev/null
+++ b/build_number_generator/__init__.py
@@ -0,0 +1,18 @@
+from flask import Flask
+import os
+
+def create_app() -> None:
+	app_path = os.path.dirname(__file__)
+	app = Flask(__name__, root_path=app_path, instance_path=os.path.join(app_path, "instance"), instance_relative_config=True)
+
+	app.config.from_pyfile("config.py")
+
+	app.app_context()
+
+	with app.app_context():
+		from . import database
+		database.init()
+
+		from .controller import build_number
+
+	return app
diff --git a/build_number_generator/controller/build_number.py b/build_number_generator/controller/build_number.py
new file mode 100644
index 0000000..4156d2d
--- /dev/null
+++ b/build_number_generator/controller/build_number.py
@@ -0,0 +1,100 @@
+from flask import Flask, jsonify, current_app, request
+from build_number_generator.database import get_database
+
+import hashlib
+
+MIN_COMMIT_HASH_LENGTH = 16
+
+def hash_token(token: str) -> str:
+	digest = hashlib.blake2b(digest_size=64)
+	digest.update(str.encode(token))
+	return digest.hexdigest()
+
+
+def fail(status_message: str, status_code: int = 400) -> tuple:
+	response = {}
+	response["status"] = status_code
+	response["message"] = status_message
+	return response, status_code
+
+
+@current_app.errorhandler(405)
+def method_not_allowed(e) -> tuple:
+    return fail("Method not allowed", 405)
+
+
+@current_app.route("/build-number", methods=["POST"])
+@current_app.route("/build-number/<string:series>", methods=["POST"])
+@current_app.route("/build-number/<string:series>/<string:commit>", methods=["POST"])
+def build_number(series=None, commit=None):
+
+	token = request.form.get("token")
+
+	if not token:
+		return fail("Unautherized", 401)
+
+	if not hash_token(token) in current_app.config["AUTHORIZED_HASHES"]:
+		return fail("Unautherized", 401)
+
+	if not series:
+		return fail("Required parameter not provided. Format: /build-number/<series>/<commit_hash>")
+
+	if series.count(".") != 1:
+		return fail("Invalid parameter: series. Format: <major>.<minor>")
+
+	major, minor = series.split(".")
+
+	if not major.isnumeric() or not minor.isnumeric():
+		return fail("Invalid parameter: series. Format: <major>.<minor>")
+
+	major = int(major)
+	minor = int(minor)
+
+	if not commit:
+		return fail("Required parameter not provided. Format: /build-number/<series>/<commit_hash>")
+
+	if len(commit) < MIN_COMMIT_HASH_LENGTH:
+		return fail("Invalid parameter: commit. Must be at least %i characters long" % (MIN_COMMIT_HASH_LENGTH))
+
+	response = {}
+
+	db = get_database()
+
+	# Find or insert series
+	result = db.execute("SELECT * FROM series WHERE name='%i.%i'" % (major, minor))
+	row = result.fetchone()
+
+	if row is not None:
+		series_id = row["id"]
+		response["message"] = "Known series. "
+	else:
+		cursor = db.execute("INSERT INTO series VALUES (NULL, '%i.%i', NULL)" % (major, minor))
+		series_id = cursor.lastrowid
+		response["message"] = "Unknown series. "
+
+	# Find or insert build number
+	result = db.execute("SELECT * FROM build WHERE series_id=%i AND commit_hash='%s'" % (series_id, commit))
+	row = result.fetchone()
+
+	if row is not None:
+		build_number = row["build_number"]
+
+		response["message"] += "Known commit hash."
+		response["stauts"] = 200
+	else:
+		result = db.execute("SELECT build_number FROM build WHERE series_id=%i ORDER BY build_number DESC LIMIT 1" % (series_id))
+		row = result.fetchone()
+		build_number = (row["build_number"] + 1) if row is not None else 1
+		cursor = db.execute("INSERT INTO build VALUES (NULL, %i, '%s', %i, NULL)" % (series_id, commit, build_number))
+
+		response["message"] += "Unknown commit hash. New build number created."
+		response["stauts"] = 201
+
+	db.commit()
+
+	response["commit_hash"] = commit
+	response["series"] = "%i.%i" % (major, minor)
+	response["series_id"] = series_id
+	response["build_number"] = build_number
+
+	return response, response["stauts"]
diff --git a/build_number_generator/database.py b/build_number_generator/database.py
new file mode 100644
index 0000000..9c7f401
--- /dev/null
+++ b/build_number_generator/database.py
@@ -0,0 +1,45 @@
+import sqlite3
+
+import click
+from flask import current_app, g
+
+
+def get_database() -> sqlite3.Connection:
+	"""Gets the database connection for the current request. If this function is called for the first time for the given request,
+	this function also connects to the database, whereas later calls will simply reuse that connection"""
+	if "database" not in g:
+		g.database = sqlite3.connect(
+			current_app.config["DATABASE"], detect_types=sqlite3.PARSE_DECLTYPES
+		)
+		g.database.row_factory = sqlite3.Row
+
+	return g.database
+
+
+def close_database(_ = None) -> None:
+	"""If a connection to the database has been established, this function closes it again"""
+	database: sqlite3.Connection = g.pop("database", None)
+
+	if database is not None:
+		database.close()
+
+
+def init_database() -> None:
+	"""This function (re)creates the database from scratch. If the database existed
+	before, its contents will be dropped"""
+	database: sqlite3.Connection = get_database()
+
+	with current_app.open_resource("schema.sql") as file:
+		database.executescript(file.read().decode("utf-8"))
+
+
+@click.command("init-db")
+def init_db_command() -> None:
+	"""Clear existing data and create new tables."""
+	init_database()
+	click.echo("Database initialized")
+
+
+def init() -> None:
+	current_app.teardown_appcontext(close_database)
+	current_app.cli.add_command(init_db_command)
diff --git a/build_number_generator/schema.sql b/build_number_generator/schema.sql
new file mode 100644
index 0000000..baa146b
--- /dev/null
+++ b/build_number_generator/schema.sql
@@ -0,0 +1,18 @@
+DROP TABLE IF EXISTS series;
+DROP TABLE IF EXISTS build;
+
+CREATE TABLE series (
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	name TEXT NOT NULL,
+	created_on DEFAULT CURRENT_TIMESTAMP
+);
+
+CREATE TABLE build (
+	id INTEGER PRIMARY KEY AUTOINCREMENT,
+	series_id INTEGER NOT NULL,
+	commit_hash TEXT NOT NULL,
+	build_number INTEGER NOT NULL,
+	created_on DEFAULT CURRENT_TIMESTAMP,
+	UNIQUE(series_id, commit_hash),
+	FOREIGN KEY (series_id) REFERENCES series (id) 
+);
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..2077213
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1 @@
+Flask
\ No newline at end of file
diff --git a/setup b/setup
new file mode 100755
index 0000000..490a45b
--- /dev/null
+++ b/setup
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+PYTHON_HOST_BIN=python
+
+which $PYTHON_HOST_BIN
+
+if [ $? -ne 0 ]; then
+	PYTHON_HOST_BIN=python3
+fi
+
+which $PYTHON_HOST_BIN
+
+if [ $? -ne 0 ]; then
+	echo "python executable not found"
+	exit 1
+fi
+
+$PYTHON_HOST_BIN --version
+
+$PYTHON_HOST_BIN -m venv venv
+venv/bin/pip install -r requirements.txt
+
+. venv/bin/activate
diff --git a/test/__init__.py b/test/__init__.py
new file mode 100644
index 0000000..4287ca8
--- /dev/null
+++ b/test/__init__.py
@@ -0,0 +1 @@
+#
\ No newline at end of file
diff --git a/test/requirements.txt b/test/requirements.txt
new file mode 100644
index 0000000..16d3b77
--- /dev/null
+++ b/test/requirements.txt
@@ -0,0 +1,2 @@
+pytest
+requests
\ No newline at end of file
diff --git a/test/test_build_number_generator.py b/test/test_build_number_generator.py
new file mode 100644
index 0000000..1a12273
--- /dev/null
+++ b/test/test_build_number_generator.py
@@ -0,0 +1,58 @@
+import pytest
+import json
+
+@pytest.fixture()
+def app():
+	from build_number_generator import create_app
+	from build_number_generator.database import init_database
+
+	app = create_app()
+	app.testing = True
+
+	app.config.update({
+		"DATABASE": "/tmp/test.sqlite",
+		"AUTHORIZED_HASHES": {
+			# 'testpassword'
+			"ebe5a79f942bab98b3c122ceb72a9c23fb21991848cddb9ad4ce8a209c8269c25eb5f5146427afc23ef588de61798b38451282339e2c637c6dec51d635ab50c4"
+		}
+	})
+
+	with app.app_context():
+		init_database()
+
+	yield app
+
+@pytest.fixture()
+def app_context(app):
+	with app.app_context():
+		yield app
+
+
+@pytest.fixture()
+def client(app_context):
+	yield app_context.test_client()
+
+
+def request(client, url, data=None):
+	response = client.post(url, data=data, headers={"Content-Type": "application/x-www-form-urlencoded"})
+	j = json.loads(response.data)
+	status = response.status_code
+	return j, status
+
+
+def test_method_1(client):
+	response = client.get("/build-number")
+	j = json.loads(response.data)
+	status = response.status_code
+	assert status == 405 and j["status"] == 405
+
+
+def test_method_2(client):
+	response = client.get("/build-number")
+	j = json.loads(response.data)
+	status = response.status_code
+	assert status == 405 and j["status"] == 405
+	#j, status = request(client, "/build-number/asd/asd", "")
+	#assert status == 400 and j["status"] == 400
+
+	#request(client, "/build-number/1.1/abcdefghijklmnopq", "token=testpassword")