diff --git a/BUILD b/BUILD
index 4b5d3ebfa..c9ca21801 100644
--- a/BUILD
+++ b/BUILD
@@ -1,41 +1,97 @@
+load("@rules_python//python:defs.bzl", "py_binary")
+load("@rules_python//python:defs.bzl", "py_library")
+load("@rules_python//python:defs.bzl", "py_test")
+
+load("@knora_py_deps//:requirements.bzl", "requirement")
+
 py_library(
     name = "knora",
     srcs = glob(["knora/knora.py"]),
+    deps = [
+        requirement("rdflib"),
+        requirement("lxml"),
+        requirement("validators"),
+        requirement("requests"),
+        requirement("jsonschema"),
+        requirement("click"),
+        requirement("rfc3987"),
+        requirement("pprint"),
+    ]
 )
 
 py_binary(
     name = "knora_create_ontology",
     srcs = ["knora/create_ontology.py"],
-    deps = ["knora"]
+    deps = [
+        "knora",
+        requirement("jsonschema"),
+        requirement("pprint"),
+    ]
 )
 
 py_binary(
-    name = "knora-xml-import",
+    name = "knora_xml_import",
     srcs = ["knora/xml2knora.py"],
-    deps = ["knora"]
+    deps = [
+        "knora",
+        requirement("lxml"),
+        requirement("pprint"),
+    ],
 )
 
 py_binary(
-    name = "knora-reset-triplestore",
+    name = "knora_reset_triplestore",
     srcs = ["knora/reset_triplestore.py"],
-    deps = ["knora"]
+    deps = [":knora"],
 )
 
 py_binary(
     name = "knoractl",
     srcs = ["knora/knoractl.py"],
-    deps = ["knora"]
+    deps = [":knora"],
+)
+
+py_test(
+    name = "test_create_ontology",
+    srcs = ["test/test_create_ontology.py"],
+    deps = [":knora"],
+)
+
+py_test(
+    name = "test_create_resource",
+    srcs = ["test/test_create_resource.py"],
+    deps = [
+        ":knora",
+        requirement("pprint"),
+    ],
 )
 
 py_test(
     name = "test_knora",
-    srcs = ["tests/test_knora.py"],
-    deps = ["knora"],
+    srcs = ["test/test_knora.py"],
+    deps = [":knora"],
 )
 
 test_suite(
     name = "all_tests",
     tests = [
+        "test_create_ontology",
+        "test_create_resource",
         "test_knora",
     ],
 )
+
+py_library(
+    name = "test_lib",
+    srcs = glob(["test/*.py"]),
+    deps = [
+        ":knora",
+    ],
+)
+
+py_binary(
+    name = "run_tests",
+    main = "test/run.py",
+    srcs = ["test/run.py"],
+    deps = ["test_lib"],
+)
diff --git a/Makefile b/Makefile
index 9035f41c7..fcd8b5d9e 100644
--- a/Makefile
+++ b/Makefile
@@ -16,8 +16,13 @@ serve-docs: ## serve docs for local viewing
 publish-docs: ## build and publish docs to Github Pages
 	mkdocs gh-deploy
 
+.PHONY: install-requirements
+install-requirements: ## install requirements
+	pip3 install -r requirements.txt
+
+.PHONY: test
 test: ## runs all tests
-	python3 -m pytest
+	cd test && python3 -m unittest
 
 clean: ## cleans the project directory
 	rm -rf dist/ build/ knora.egg-info/ .pytest_cache/ site/
diff --git a/README.md b/README.md
index 0c4e0edd7..803fae6b0 100644
--- a/README.md
+++ b/README.md
@@ -33,6 +33,13 @@ $ python3 setup.py install
 The project contains a Makefile defining management tasks. Please use
 `make help` to see what is available. 
 
+## Testing
+
+```bash
+$ make install-requirements
+$ make test
+```
+
 ## Publishing to PyPi
 
 Generate distribution package. Make sure you have the latest versions of `setuptools` and `wheel` installed:
@@ -70,15 +77,7 @@ $ python3 -m twine upload dist/*
 For local development:
 
 ```bash
-$ python3 setup.py develop
-```
-
-## Testing
-
-```bash
-$ pip3 install pytest
-$ pip3 install --editable .
-$ pytest
+$ python3 setup.py --editable .
 ```
 
 ## Requirements
diff --git a/WORKSPACE b/WORKSPACE
index e69de29bb..6b66dc41e 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -0,0 +1,42 @@
+workspace(name = "knora_py")
+
+# use bazel federation (set of rule versions known to work well together)
+load("@bazel_tools//tools/build_defs/repo:http.bzl", "http_archive")
+http_archive(
+    name = "bazel_federation",
+    url = "https://github.com/bazelbuild/bazel-federation/releases/download/0.0.1/bazel_federation-0.0.1.tar.gz",
+    sha256 = "506dfbfd74ade486ac077113f48d16835fdf6e343e1d4741552b450cfc2efb53",
+)
+
+# load the initializer methods for all the rules we want to use in this workspace
+load("@bazel_federation//:repositories.bzl",
+     "rules_python",
+)
+
+# run any rule specific setups
+rules_python()
+load("@bazel_federation//setup:rules_python.bzl", "rules_python_setup")
+rules_python_setup()
+
+# load py_repositories from rules_python
+load("@rules_python//python:repositories.bzl", "py_repositories")
+py_repositories()
+
+# load pip_repositories from rules_python
+load("@rules_python//python:pip.bzl", "pip_repositories")
+pip_repositories()
+
+# allows to use requirements.txt for loading the dependencies
+load("@rules_python//python:pip.bzl", "pip_import")
+
+# This rule translates the specified requirements.txt into
+# @knora_py_deps//:requirements.bzl, which itself exposes a pip_install method.
+pip_import(
+   name = "knora_py_deps",
+   requirements = "//:requirements.txt",
+)
+
+# Load the pip_install symbol for knora_py_deps, and create the dependencies'
+# repositories.
+load("@knora_py_deps//:requirements.bzl", "pip_install")
+pip_install()
diff --git a/knora/knora.py b/knora/knora.py
index 73e96f55e..7e8d051d0 100755
--- a/knora/knora.py
+++ b/knora/knora.py
@@ -116,6 +116,7 @@ def __init__(self, server: str, prefixes: Dict[str, str] = None):
         """
         self.server = server
         self.prefixes = prefixes
+        self.token = None
 
     def login(self, email: str, password: str):
         """
@@ -142,12 +143,13 @@ def get_token(self):
         return self.token
 
     def logout(self):
-        req = requests.delete(
-            self.server + '/v2/authentication',
-            headers={'Authorization': 'Bearer ' + self.token}
-        )
-        self.on_api_error(req)
-        self.token = None
+        if self.token is not None:
+            req = requests.delete(
+                self.server + '/v2/authentication',
+                headers={'Authorization': 'Bearer ' + self.token}
+            )
+            self.on_api_error(req)
+            self.token = None
 
     def __del__(self):
         self.logout()
@@ -245,7 +247,7 @@ def create_project(
             project['logo'] = logo
 
         jsondata = json.dumps(project)
-        print(jsondata)
+        # print(jsondata)
 
         req = requests.post(self.server + "/admin/projects",
                             headers={'Content-Type': 'application/json; charset=UTF-8',
diff --git a/requirements.txt b/requirements.txt
index ccb6c7442..bc7962d65 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -6,3 +6,11 @@ twine
 pytest
 mkdocs==1.0.4
 mkdocs-material
+rdflib
+lxml
+validators
+requests
+jsonschema
+click
+rfc3987
+pprint
diff --git a/setup.py b/setup.py
index 90dd74434..3da16efe5 100644
--- a/setup.py
+++ b/setup.py
@@ -27,16 +27,16 @@
         'jsonschema',
         'click',
         'rfc3987',
-        'pprint'
+        'pprint',
     ],
     entry_points={
           'console_scripts': [
               'knora-create-ontology=knora.create_ontology:main',
               'knora-xml-import=knora.xml2knora:main',
               'knora-reset-triplestore=knora.reset_triplestore:main',
-              'knoractl=knoractl:main'
+              'knoractl=knoractl:main',
           ],
     },
     include_package_data=True,
-    zip_safe=False
+    zip_safe=False,
 )
diff --git a/tests/lists.json b/test/lists.json
similarity index 100%
rename from tests/lists.json
rename to test/lists.json
diff --git a/test/run.py b/test/run.py
new file mode 100644
index 000000000..50206bd33
--- /dev/null
+++ b/test/run.py
@@ -0,0 +1,55 @@
+"""Universal launcher for unit tests"""
+
+import argparse
+import logging
+import os
+import sys
+import unittest
+
+
+def main():
+    """Parse args, collect tests and run them"""
+    # Disable *.pyc files
+    sys.dont_write_bytecode = True
+
+    # Add ".." to module search path
+    cur_dir = os.path.dirname(os.path.realpath(__file__))
+    top_dir = os.path.abspath(os.path.join(cur_dir, os.pardir))
+    sys.path.append(top_dir)
+
+    # Parse command line arguments
+    parser = argparse.ArgumentParser(description=__doc__)
+    parser.add_argument("-v", "--verbose", action="count", default=0,
+                        help="verbosity level, use: [-v | -vv | -vvv]")
+    parser.add_argument("-s", "--start-directory", default=None,
+                        help="directory to start discovery")
+    parser.add_argument("-p", "--pattern", default="test*.py",
+                        help="pattern to match test files ('test*.py' default)")
+    parser.add_argument("test", nargs="*",
+                        help="test specs (e.g. module.TestCase.test_func)")
+    args = parser.parse_args()
+
+    if not args.start_directory:
+        args.start_directory = cur_dir
+
+    if args.verbose > 2:
+        logging.basicConfig(level=logging.DEBUG, format="DEBUG: %(message)s")
+
+    loader = unittest.TestLoader()
+    if args.test:
+        # Add particular tests
+        for test in args.test:
+            suite = unittest.TestSuite()
+            suite.addTests(loader.loadTestsFromName(test))
+    else:
+        # Find all tests
+        suite = loader.discover(args.start_directory, args.pattern)
+
+    runner = unittest.TextTestRunner(verbosity=args.verbose)
+    result = runner.run(suite)
+    return result.wasSuccessful()
+
+
+if __name__ == "__main__":
+    # NOTE: True(success) -> 0, False(fail) -> 1
+    exit(not main())
diff --git a/tests/test-onto.json b/test/test-onto.json
similarity index 100%
rename from tests/test-onto.json
rename to test/test-onto.json
diff --git a/tests/test.tif b/test/test.tif
similarity index 100%
rename from tests/test.tif
rename to test/test.tif
diff --git a/test/test_create_ontology.py b/test/test_create_ontology.py
new file mode 100644
index 000000000..0eeebe54d
--- /dev/null
+++ b/test/test_create_ontology.py
@@ -0,0 +1,12 @@
+import unittest
+
+
+class TestCreateOntology(unittest.TestCase):
+
+    @unittest.skip("not implemented")
+    def test_create_ontology(self):
+        pass
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/test/test_create_resource.py b/test/test_create_resource.py
new file mode 100644
index 000000000..52f68302a
--- /dev/null
+++ b/test/test_create_resource.py
@@ -0,0 +1,52 @@
+import unittest
+from pprint import pprint
+from knora import Knora, Sipi
+
+
+class TestCreateResource(unittest.TestCase):
+
+    @unittest.skip("not implemented")
+    def test_create_resource(self):
+        server = "http://0.0.0.0:3333"
+        sipi = "http://0.0.0.0:1024"
+        email = "root@example.com"
+        password = "test"
+        projectcode = "00FE"
+        ontoname = "KPT"
+
+        con = Knora(server)
+        con.login(email, password)
+        graph = con.get_ontology_graph('00FE', 'kpt')
+        # print(graph)
+        # exit(0)
+        schema = con.create_schema(projectcode, ontoname)
+        # pprint(schema)
+        # exit(0)
+
+        inst1_info = con.create_resource(schema, "object1", "obj1_inst1", {
+            "textprop": "Dies ist ein Text!",
+            "intprop": 7,
+            "listprop": "options:opt2",
+            "dateprop": "1966:CE:1967-05-21",
+            "decimalprop": {'value': "3.14159", 'comment': "Die Zahl PI"},
+            "geonameprop": "2661604",
+            "richtextprop": "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<text><p><strong>this is</strong> text</p> with standoff</text>",
+            "intervalprop": "13.57:15.88"
+        })
+        pprint(inst1_info)
+
+        # first upload image to SIPI
+        sipi = Sipi(sipi, con.get_token())
+        res = sipi.upload_image('test.tif')
+        pprint(res)
+
+        fileref = res['uploadedFiles'][0]['internalFilename']
+        inst2_info = con.create_resource(schema, "object2", "obj2_inst1", {
+            "titleprop": "Stained glass",
+            "linkprop": inst1_info['iri']
+        }, fileref)
+        pprint(inst2_info)
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/test/test_knora.py b/test/test_knora.py
new file mode 100644
index 000000000..afdbbb9e9
--- /dev/null
+++ b/test/test_knora.py
@@ -0,0 +1,72 @@
+import unittest
+from knora import Knora
+
+
+class TestKnora(unittest.TestCase):
+
+    def con(self, login: bool = True) -> Knora:
+        server = "http://0.0.0.0:3333"
+        email = "root@example.com"
+        password = "test"
+        # projectcode = "00FE"
+        # ontoname = "KPT"
+        con = Knora(server)
+        if login:
+            con.login(email, password)
+        return con
+
+    # resets the content of the triplestore
+    def test_reset_triplestore_content(self):
+        res = self.con(login=False).reset_triplestore_content()
+        self.assertIsNotNone(res)
+
+    # retrieves all users
+    def test_get_users(self):
+        res = self.con(login=True).get_users()
+        # print(res)
+        self.assertEqual(len(res), 19)
+
+    # retrieves user information
+    def test_get_user(self):
+        res = self.con(login=True).get_user_by_iri(user_iri='http://rdfh.ch/users/root')
+        # print(res)
+        self.assertEqual(res["username"], "root")
+
+    # creates a user
+    def test_create_user(self):
+        connection = self.con(login=True)
+        user = {
+            "username": "testtest",
+            "email": "testtest@example.com",
+            "given_name": "test_given",
+            "family_name": "test_family",
+            "password": "test",
+            "lang": "en"
+        }
+
+        user_iri = connection.create_user(
+            username=user["username"],
+            email=user["email"],
+            given_name=user["given_name"],
+            family_name=user["family_name"],
+            password=user["password"],
+            lang=user["lang"] if user.get("lang") is not None else "en")
+
+        # print(user_iri)
+
+        # check that the created user exists
+        res = connection.get_user_by_iri(user_iri)
+        self.assertEqual(res["username"], "testtest")
+        self.assertEqual(res["email"], "testtest@example.com")
+
+        # logout current user
+        connection.logout()
+        self.assertIsNone(connection.get_token())
+
+        # login as newly created user
+        connection.login(res["email"], "test")
+        self.assertIsNotNone(connection.get_token())
+
+
+if __name__ == "__main__":
+    unittest.main()
diff --git a/tests/conftest.py b/tests/conftest.py
deleted file mode 100644
index fbf9341f8..000000000
--- a/tests/conftest.py
+++ /dev/null
@@ -1,12 +0,0 @@
-import os
-
-import pytest
-
-import knora.create_ontology
-
-
-@pytest.fixture
-def create_test_ontology_fixture():
-    dir_path = os.path.dirname(os.path.realpath(__file__))
-    os.chdir(dir_path)
-    knora.create_ontology.main(['./test-onto.json'])
diff --git a/tests/test_create_ontology.py b/tests/test_create_ontology.py
deleted file mode 100644
index 28d2d3b21..000000000
--- a/tests/test_create_ontology.py
+++ /dev/null
@@ -1,7 +0,0 @@
-import pytest
-
-
-@pytest.mark.skip(reason="broken")
-def test_create_test_onto(create_test_ontology_fixture):
-    pass
-
diff --git a/tests/test_create_resource.py b/tests/test_create_resource.py
deleted file mode 100644
index d6ae52990..000000000
--- a/tests/test_create_resource.py
+++ /dev/null
@@ -1,50 +0,0 @@
-import os
-from typing import List, Set, Dict, Tuple, Optional
-from pprint import pprint
-import argparse
-import json
-from jsonschema import validate
-from knora import KnoraError, Knora, Sipi
-import pytest
-
-
-@pytest.mark.skip(reason="broken")
-def test_create_resource(create_test_ontology_fixture):
-    server = "http://0.0.0.0:3333"
-    sipi = "http://0.0.0.0:1024",
-    user = "root@example.com",
-    password = "test"
-    projectcode = "00FE"
-    ontoname = "KPT"
-
-    con = Knora(server, user, password)
-    graph = con.get_ontology_graph('00FE', 'kpt')
-    # print(graph)
-    # exit(0)
-    schema = con.create_schema(projectcode, ontoname)
-    # pprint(schema)
-    # exit(0)
-
-    inst1_info = con.create_resource(schema, "object1", "obj1_inst1", {
-        "textprop": "Dies ist ein Text!",
-        "intprop": 7,
-        "listprop": "options:opt2",
-        "dateprop": "1966:CE:1967-05-21",
-        "decimalprop": {'value': "3.14159", 'comment': "Die Zahl PI"},
-        "geonameprop": "2661604",
-        "richtextprop": "<?xml version=\"1.0\" encoding=\"UTF-8\"?>\n<text><p><strong>this is</strong> text</p> with standoff</text>",
-        "intervalprop": "13.57:15.88"
-    })
-    pprint(inst1_info)
-
-    # first upload image to SIPI
-    sipi = Sipi(sipi, con.get_token())
-    res = sipi.upload_image('test.tif')
-    pprint(res)
-
-    fileref = res['uploadedFiles'][0]['internalFilename']
-    inst2_info = con.create_resource(schema, "object2", "obj2_inst1", {
-        "titleprop": "Stained glass",
-        "linkprop": inst1_info['iri']
-    }, fileref)
-    pprint(inst2_info)
\ No newline at end of file
diff --git a/tests/test_knora.py b/tests/test_knora.py
deleted file mode 100644
index e2ed2fde0..000000000
--- a/tests/test_knora.py
+++ /dev/null
@@ -1,74 +0,0 @@
-import pytest
-from knora import Knora
-
-
-@pytest.fixture()
-def con():
-    def _con(login: bool = True) -> Knora:
-        server = "http://0.0.0.0:3333"
-        email = "root@example.com"
-        password = "test"
-        # projectcode = "00FE"
-        # ontoname = "KPT"
-        con = Knora(server)
-        if login:
-            con.login(email, password)
-        return con
-
-    return _con
-
-
-# resets the content of the triplestore
-def test_reset_triplestore_content(con):
-    res = con(login=False).reset_triplestore_content()
-    assert res
-
-
-# retrieves all users
-def test_get_users(con):
-    res = con(login=True).get_users()
-    print(res)
-    assert (len(res) == 18)
-
-
-# retrieves user information
-def test_get_user(con):
-    res = con(login=True).get_user_by_iri(user_iri='http://rdfh.ch/users/root')
-    print(res)
-    assert (res["username"] == "root")
-
-
-# creates a user
-def test_create_user(con):
-    connection = con(login=True)
-    user = {
-        "username": "testtest",
-        "email": "testtest@example.com",
-        "given_name": "test_given",
-        "family_name": "test_family",
-        "password": "test",
-        "lang": "en"
-    }
-
-    user_iri = connection.create_user(
-        username=user["username"],
-        email=user["email"],
-        given_name=user["given_name"],
-        family_name=user["family_name"],
-        password=user["password"],
-        lang=user["lang"] if user.get("lang") is not None else "en")
-
-    print(user_iri)
-
-    # check that the created user exists
-    res = connection.get_user_by_iri(user_iri)
-    assert (res["username"] == "testtest")
-    assert (res["email"] == "testtest@example.com")
-
-    # logout
-    connection.logout()
-    assert (connection.get_token() is None)
-
-    # login
-    connection.login(res["email"], "test")
-    assert (connection.get_token() is not None)