diff --git a/.coveragerc b/.coveragerc
deleted file mode 100644
index f2c3d0b8..00000000
--- a/.coveragerc
+++ /dev/null
@@ -1,7 +0,0 @@
-[run]
-branch = True
-
-[report]
-exclude_lines =
-    pragma: no cover
-    raise NotImplementedError
diff --git a/.travis.yml b/.travis.yml
index 12fd07a6..4da6eb14 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -13,12 +13,9 @@ addons:
 install:
   - pip install codecov
   - pip install tox tox-travis
-  - pip install isort black
 script:
   - codecov --version
   - tox
-  - isort --check src tests
-  - black -l 100 --check src tests
 after_success:
   - codecov
 notifications:
diff --git a/doc/conf.py b/doc/conf.py
index 1cc6d858..28cd9204 100644
--- a/doc/conf.py
+++ b/doc/conf.py
@@ -31,36 +31,38 @@
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
 # ones.
-extensions = ['sphinx.ext.autodoc',
-    'sphinx.ext.intersphinx',
-    'sphinx.ext.coverage',
-    'sphinx.ext.viewcode']
+extensions = [
+    "sphinx.ext.autodoc",
+    "sphinx.ext.intersphinx",
+    "sphinx.ext.coverage",
+    "sphinx.ext.viewcode",
+]
 
 # Add any paths that contain templates here, relative to this directory.
-templates_path = ['_templates']
+templates_path = ["_templates"]
 
 # The suffix(es) of source filenames.
 # You can specify multiple suffix as a list of string:
 #
 # source_suffix = ['.rst', '.md']
-source_suffix = '.rst'
+source_suffix = ".rst"
 
 # The master toctree document.
-master_doc = 'index'
+master_doc = "index"
 
 # General information about the project.
-project = 'CryptoJWT'
-copyright = '2018, Roland Hedberg'
-author = 'Roland Hedberg'
+project = "CryptoJWT"
+copyright = "2018, Roland Hedberg"
+author = "Roland Hedberg"
 
 # The version info for the project you're documenting, acts as replacement for
 # |version| and |release|, also used in various other places throughout the
 # built documents.
 #
 # The short X.Y version.
-version = '0.4'
+version = "0.4"
 # The full version, including alpha/beta/rc tags.
-release = '0.4'
+release = "0.4"
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.
@@ -72,10 +74,10 @@
 # List of patterns, relative to source directory, that match files and
 # directories to ignore when looking for source files.
 # This patterns also effect to html_static_path and html_extra_path
-exclude_patterns = ['_build', 'Thumbs.db', '.DS_Store']
+exclude_patterns = ["_build", "Thumbs.db", ".DS_Store"]
 
 # The name of the Pygments (syntax highlighting) style to use.
-pygments_style = 'sphinx'
+pygments_style = "sphinx"
 
 # If true, `todo` and `todoList` produce output, else they produce nothing.
 todo_include_todos = False
@@ -86,7 +88,7 @@
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 #
-html_theme = 'default'
+html_theme = "default"
 
 # Theme options are theme-specific and customize the look and feel of a theme
 # further.  For a list of options available for each theme, see the
@@ -97,7 +99,7 @@
 # Add any paths that contain custom static files (such as style sheets) here,
 # relative to this directory. They are copied after the builtin static files,
 # so a file named "default.css" will overwrite the builtin "default.css".
-html_static_path = ['_static']
+html_static_path = ["_static"]
 
 # Custom sidebar templates, must be a dictionary that maps document names
 # to template names.
@@ -105,9 +107,9 @@
 # This is required for the alabaster theme
 # refs: http://alabaster.readthedocs.io/en/latest/installation.html#sidebars
 html_sidebars = {
-    '**': [
-        'relations.html',  # needs 'show_related': True theme option to display
-        'searchbox.html',
+    "**": [
+        "relations.html",  # needs 'show_related': True theme option to display
+        "searchbox.html",
     ]
 }
 
@@ -115,7 +117,7 @@
 # -- Options for HTMLHelp output ------------------------------------------
 
 # Output file base name for HTML help builder.
-htmlhelp_basename = 'CryptoJWTdoc'
+htmlhelp_basename = "CryptoJWTdoc"
 
 
 # -- Options for LaTeX output ---------------------------------------------
@@ -124,15 +126,12 @@
     # The paper size ('letterpaper' or 'a4paper').
     #
     # 'papersize': 'letterpaper',
-
     # The font size ('10pt', '11pt' or '12pt').
     #
     # 'pointsize': '10pt',
-
     # Additional stuff for the LaTeX preamble.
     #
     # 'preamble': '',
-
     # Latex figure (float) alignment
     #
     # 'figure_align': 'htbp',
@@ -142,8 +141,7 @@
 # (source start file, target name, title,
 #  author, documentclass [howto, manual, or own class]).
 latex_documents = [
-    (master_doc, 'CryptoJWT.tex', 'CryptoJWT Documentation',
-     'Roland Hedberg', 'manual'),
+    (master_doc, "CryptoJWT.tex", "CryptoJWT Documentation", "Roland Hedberg", "manual"),
 ]
 
 
@@ -151,10 +149,7 @@
 
 # One entry per manual page. List of tuples
 # (source start file, name, description, authors, manual section).
-man_pages = [
-    (master_doc, 'cryptojwt', 'CryptoJWT Documentation',
-     [author], 1)
-]
+man_pages = [(master_doc, "cryptojwt", "CryptoJWT Documentation", [author], 1)]
 
 
 # -- Options for Texinfo output -------------------------------------------
@@ -163,13 +158,17 @@
 # (source start file, target name, title, author,
 #  dir menu entry, description, category)
 texinfo_documents = [
-    (master_doc, 'CryptoJWT', 'CryptoJWT Documentation',
-     author, 'CryptoJWT', 'One line description of project.',
-     'Miscellaneous'),
+    (
+        master_doc,
+        "CryptoJWT",
+        "CryptoJWT Documentation",
+        author,
+        "CryptoJWT",
+        "One line description of project.",
+        "Miscellaneous",
+    ),
 ]
 
 
-
-
 # Example configuration for intersphinx: refer to the Python standard library.
-intersphinx_mapping = {'https://docs.python.org/': None}
+intersphinx_mapping = {"https://docs.python.org/": None}
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 00000000..d639eb5e
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,21 @@
+# PEP 518: https://www.python.org/dev/peps/pep-0518/
+
+[tool.black]
+line-length = 100
+
+[tool.isort]
+force_single_line = true
+known_first_party = "cryptojwt"
+include_trailing_comma = true
+force_grid_wrap = 0
+use_parentheses = true
+line_length = 100
+
+[tool.coverage.run]
+branch = true
+
+[tool.coverage.report]
+exclude_lines = [
+    "pragma: no cover",
+    "raise NotImplementedError",
+]
diff --git a/setup.cfg b/setup.cfg
deleted file mode 100644
index 6a04d9e3..00000000
--- a/setup.cfg
+++ /dev/null
@@ -1,7 +0,0 @@
-[isort]
-force_single_line = 1
-known_first_party = cryptojwt
-include_trailing_comma = True
-force_grid_wrap = 0
-use_parentheses = True
-line_length = 100
diff --git a/setup.py b/setup.py
index fe415e37..d62ad040 100644
--- a/setup.py
+++ b/setup.py
@@ -20,13 +20,12 @@
 
 from setuptools import setup
 
-__author__ = 'Roland Hedberg'
+__author__ = "Roland Hedberg"
 
-with open('src/cryptojwt/__init__.py', 'r') as fd:
-    version = re.search(r'^__version__\s*=\s*[\'"]([^\'"]*)[\'"]',
-                        fd.read(), re.MULTILINE).group(1)
+with open("src/cryptojwt/__init__.py", "r") as fd:
+    version = re.search(r'^__version__\s*=\s*[\'"]([^\'"]*)[\'"]', fd.read(), re.MULTILINE).group(1)
 
-tests_requires = ['responses', 'pytest', 'isort>=5.0.2', 'black']
+tests_requires = ["responses", "pytest", "isort>=5.0.2", "black"]
 
 setup(
     name="cryptojwt",
@@ -35,8 +34,14 @@
     author="Roland Hedberg",
     author_email="roland@catalogix.se",
     license="Apache 2.0",
-    packages=["cryptojwt", "cryptojwt/jwe", "cryptojwt/jwk", "cryptojwt/jws", "cryptojwt/tools",
-              "cryptojwt/serialize"],
+    packages=[
+        "cryptojwt",
+        "cryptojwt/jwe",
+        "cryptojwt/jwk",
+        "cryptojwt/jws",
+        "cryptojwt/tools",
+        "cryptojwt/serialize",
+    ],
     package_dir={"": "src"},
     classifiers=[
         "Development Status :: 4 - Beta",
@@ -45,22 +50,22 @@
         "Programming Language :: Python :: 3.5",
         "Programming Language :: Python :: 3.6",
         "Programming Language :: Python :: 3.7",
-        "Programming Language :: Python :: 3.8"
+        "Programming Language :: Python :: 3.8",
     ],
     install_requires=["cryptography", "requests"],
-    tests_require=['pytest'],
+    tests_require=["pytest"],
     zip_safe=False,
     extras_require={
-        'testing': tests_requires,
-        'docs': ['Sphinx', 'sphinx-autobuild', 'alabaster'],
-        'quality': ['isort>=5.0.2', 'black'],
+        "testing": tests_requires,
+        "docs": ["Sphinx", "sphinx-autobuild", "alabaster"],
+        "quality": ["isort>=5.0.2", "black"],
     },
-    scripts=glob.glob('script/*.py'),
+    scripts=glob.glob("script/*.py"),
     entry_points={
         "console_scripts": [
             "jwkgen = cryptojwt.tools.keygen:main",
             "jwkconv = cryptojwt.tools.keyconv:main",
             "jwtpeek = cryptojwt.tools.jwtpeek:main",
         ]
-    }
+    },
 )
diff --git a/src/cryptojwt/__init__.py b/src/cryptojwt/__init__.py
index a2eb935d..1ae167ce 100644
--- a/src/cryptojwt/__init__.py
+++ b/src/cryptojwt/__init__.py
@@ -21,7 +21,7 @@
 except ImportError:
     pass
 
-__version__ = "1.1.0"
+__version__ = "1.2.0"
 
 logger = logging.getLogger(__name__)
 
diff --git a/src/cryptojwt/jwe/__init__.py b/src/cryptojwt/jwe/__init__.py
index 17776e0e..f0e511bb 100644
--- a/src/cryptojwt/jwe/__init__.py
+++ b/src/cryptojwt/jwe/__init__.py
@@ -22,7 +22,14 @@
         "ECDH-ES+A192KW",
         "ECDH-ES+A256KW",
     ],
-    "enc": ["A128CBC-HS256", "A192CBC-HS384", "A256CBC-HS512", "A128GCM", "A192GCM", "A256GCM",],
+    "enc": [
+        "A128CBC-HS256",
+        "A192CBC-HS384",
+        "A256CBC-HS512",
+        "A128GCM",
+        "A192GCM",
+        "A256GCM",
+    ],
 }
 
 
diff --git a/src/cryptojwt/jwe/aes.py b/src/cryptojwt/jwe/aes.py
index 625d0a6e..20ea7d78 100644
--- a/src/cryptojwt/jwe/aes.py
+++ b/src/cryptojwt/jwe/aes.py
@@ -18,8 +18,7 @@
 
 
 class AES_CBCEncrypter(Encrypter):
-    """
-    """
+    """"""
 
     def __init__(self, key_len=32, key=None, msg_padding="PKCS7"):
         Encrypter.__init__(self)
diff --git a/src/cryptojwt/jwe/jwe_ec.py b/src/cryptojwt/jwe/jwe_ec.py
index 911a6ea3..3321a8e1 100644
--- a/src/cryptojwt/jwe/jwe_ec.py
+++ b/src/cryptojwt/jwe/jwe_ec.py
@@ -157,7 +157,12 @@ def dec_setup(self, token, key=None, **kwargs):
                 raise Exception("Unknown key length for algorithm")
 
             self.cek = ecdh_derive_key(
-                key, epubkey.pub_key, apu, apv, str(self.headers["enc"]).encode(), dk_len,
+                key,
+                epubkey.pub_key,
+                apu,
+                apv,
+                str(self.headers["enc"]).encode(),
+                dk_len,
             )
         elif self.headers["alg"] in [
             "ECDH-ES+A128KW",
diff --git a/src/cryptojwt/jwe/jwe_rsa.py b/src/cryptojwt/jwe/jwe_rsa.py
index dd4324d8..f34b1331 100644
--- a/src/cryptojwt/jwe/jwe_rsa.py
+++ b/src/cryptojwt/jwe/jwe_rsa.py
@@ -85,7 +85,7 @@ def encrypt(self, key, iv="", cek="", **kwargs):
         return jwe.pack(parts=[jwe_enc_key, iv, ctxt, tag])
 
     def decrypt(self, token, key, cek=None):
-        """ Decrypts a JWT
+        """Decrypts a JWT
 
         :param token: The JWT
         :param key: A key to use for decrypting
diff --git a/src/cryptojwt/jwe/jwekey.py b/src/cryptojwt/jwe/jwekey.py
index faa6093e..31a1c8ae 100644
--- a/src/cryptojwt/jwe/jwekey.py
+++ b/src/cryptojwt/jwe/jwekey.py
@@ -38,7 +38,7 @@ def alg2keytype(self, alg):
         return alg2keytype(alg)
 
     def enc_setup(self, enc_alg, msg, auth_data=b"", key=None, iv=""):
-        """ Encrypt JWE content.
+        """Encrypt JWE content.
 
         :param enc_alg: The JWE "enc" value specifying the encryption algorithm
         :param msg: The plain text message
@@ -62,7 +62,7 @@ def enc_setup(self, enc_alg, msg, auth_data=b"", key=None, iv=""):
 
     @staticmethod
     def _decrypt(enc, key, ctxt, iv, tag, auth_data=b""):
-        """ Decrypt JWE content.
+        """Decrypt JWE content.
 
         :param enc: The JWE "enc" value specifying the encryption algorithm
         :param key: Key (CEK)
diff --git a/src/cryptojwt/jwe/rsa.py b/src/cryptojwt/jwe/rsa.py
index 691c3e59..8e7cc4fe 100644
--- a/src/cryptojwt/jwe/rsa.py
+++ b/src/cryptojwt/jwe/rsa.py
@@ -20,7 +20,9 @@ def encrypt(self, msg, key, sign_padding="pkcs1_padding"):
         return key.encrypt(
             msg,
             _padding(
-                mgf=padding.MGF1(algorithm=_chosen_hash()), algorithm=_chosen_hash(), label=None,
+                mgf=padding.MGF1(algorithm=_chosen_hash()),
+                algorithm=_chosen_hash(),
+                label=None,
             ),
         )
 
diff --git a/src/cryptojwt/jwk/jwk.py b/src/cryptojwt/jwk/jwk.py
index 86f41c47..c9e32904 100644
--- a/src/cryptojwt/jwk/jwk.py
+++ b/src/cryptojwt/jwk/jwk.py
@@ -93,7 +93,9 @@ def key_from_jwk_dict(jwk_dict, private=None):
         else:
             # Ecdsa public key.
             ec_pub_numbers = ec.EllipticCurvePublicNumbers(
-                base64url_to_long(_jwk_dict["x"]), base64url_to_long(_jwk_dict["y"]), curve,
+                base64url_to_long(_jwk_dict["x"]),
+                base64url_to_long(_jwk_dict["y"]),
+                curve,
             )
             _jwk_dict["pub_key"] = ec_pub_numbers.public_key(backends.default_backend())
         return ECKey(**_jwk_dict)
diff --git a/src/cryptojwt/jwk/rsa.py b/src/cryptojwt/jwk/rsa.py
index 07de5a6a..e98cb236 100644
--- a/src/cryptojwt/jwk/rsa.py
+++ b/src/cryptojwt/jwk/rsa.py
@@ -128,7 +128,7 @@ def rsa_eq(key1, key2):
 
 
 def x509_rsa_load(txt):
-    """ So I get the same output format as loads produces
+    """So I get the same output format as loads produces
     :param txt:
     :return:
     """
@@ -172,10 +172,10 @@ def rsa_construct_private(numbers):
     try:
         cnum["iqmp"] = numbers["di"]
     except KeyError:
-        cnum["iqmp"] = rsa.rsa_crt_iqmp(cnum["p"], cnum["p"])
+        cnum["iqmp"] = rsa.rsa_crt_iqmp(cnum["p"], cnum["q"])
     else:
         if not numbers["di"]:
-            cnum["iqmp"] = rsa.rsa_crt_iqmp(cnum["p"], cnum["p"])
+            cnum["iqmp"] = rsa.rsa_crt_iqmp(cnum["p"], cnum["q"])
 
     rpubn = rsa.RSAPublicNumbers(e=numbers["e"], n=numbers["n"])
     rprivn = rsa.RSAPrivateNumbers(public_numbers=rpubn, **cnum)
diff --git a/src/cryptojwt/jws/jws.py b/src/cryptojwt/jws/jws.py
index b24b0919..c9b334ee 100644
--- a/src/cryptojwt/jws/jws.py
+++ b/src/cryptojwt/jws/jws.py
@@ -321,7 +321,11 @@ def verify_json(self, jws, keys=None, allow_none=False, at_least_one=False):
         for _sign in _signs:
             protected_headers = _sign.get("protected", "")
             token = b".".join(
-                [protected_headers.encode(), _payload.encode(), _sign["signature"].encode(),]
+                [
+                    protected_headers.encode(),
+                    _payload.encode(),
+                    _sign["signature"].encode(),
+                ]
             )
 
             unprotected_headers = _sign.get("header", {})
diff --git a/src/cryptojwt/jws/pss.py b/src/cryptojwt/jws/pss.py
index 71cbb3d6..a7443ddb 100644
--- a/src/cryptojwt/jws/pss.py
+++ b/src/cryptojwt/jws/pss.py
@@ -38,7 +38,8 @@ def sign(self, msg, key):
         sig = key.sign(
             digest,
             padding.PSS(
-                mgf=padding.MGF1(self.hash_algorithm()), salt_length=padding.PSS.MAX_LENGTH,
+                mgf=padding.MGF1(self.hash_algorithm()),
+                salt_length=padding.PSS.MAX_LENGTH,
             ),
             utils.Prehashed(self.hash_algorithm()),
         )
@@ -59,7 +60,8 @@ def verify(self, msg, signature, key):
                 signature,
                 msg,
                 padding.PSS(
-                    mgf=padding.MGF1(self.hash_algorithm()), salt_length=padding.PSS.MAX_LENGTH,
+                    mgf=padding.MGF1(self.hash_algorithm()),
+                    salt_length=padding.PSS.MAX_LENGTH,
                 ),
                 self.hash_algorithm(),
             )
diff --git a/src/cryptojwt/jws/utils.py b/src/cryptojwt/jws/utils.py
index 171e7d00..8ee30953 100644
--- a/src/cryptojwt/jws/utils.py
+++ b/src/cryptojwt/jws/utils.py
@@ -11,7 +11,7 @@
 
 
 def left_hash(msg, func="HS256"):
-    """ Calculate left hash as described in
+    """Calculate left hash as described in
     https://openid.net/specs/openid-connect-core-1_0.html#CodeIDToken
     for at_hash and in
     for c_hash
diff --git a/src/cryptojwt/key_bundle.py b/src/cryptojwt/key_bundle.py
index 9e7e7520..9b2f200a 100755
--- a/src/cryptojwt/key_bundle.py
+++ b/src/cryptojwt/key_bundle.py
@@ -402,7 +402,9 @@ def do_remote(self):
 
         else:
             LOGGER.warning(
-                "HTTP status %d reading remote JWKS from %s", _http_resp.status_code, self.source,
+                "HTTP status %d reading remote JWKS from %s",
+                _http_resp.status_code,
+                self.source,
             )
             raise UpdateFailed(REMOTE_FAILED.format(self.source, _http_resp.status_code))
         self.last_updated = time.time()
diff --git a/src/cryptojwt/key_jar.py b/src/cryptojwt/key_jar.py
index 9c040b70..4b58bfe7 100755
--- a/src/cryptojwt/key_jar.py
+++ b/src/cryptojwt/key_jar.py
@@ -762,7 +762,12 @@ def build_keyjar(key_conf, kid_template="", keyjar=None, issuer_id="", storage=N
 
 @deprecated_alias(issuer="issuer_id", owner="issuer_id")
 def init_key_jar(
-    public_path="", private_path="", key_defs="", issuer_id="", read_only=True, storage=None,
+    public_path="",
+    private_path="",
+    key_defs="",
+    issuer_id="",
+    read_only=True,
+    storage=None,
 ):
     """
     A number of cases here:
@@ -805,7 +810,10 @@ def init_key_jar(
     """
 
     _issuer = init_key_issuer(
-        public_path=public_path, private_path=private_path, key_defs=key_defs, read_only=read_only,
+        public_path=public_path,
+        private_path=private_path,
+        key_defs=key_defs,
+        read_only=read_only,
     )
 
     if _issuer is None:
diff --git a/src/cryptojwt/tools/keyconv.py b/src/cryptojwt/tools/keyconv.py
index c12c8d5c..83f0b2d0 100644
--- a/src/cryptojwt/tools/keyconv.py
+++ b/src/cryptojwt/tools/keyconv.py
@@ -115,7 +115,10 @@ def pem2jwk(
 
 
 def export_jwk(
-    jwk: JWK, private: bool = False, encrypt: bool = False, passphrase: Optional[str] = None,
+    jwk: JWK,
+    private: bool = False,
+    encrypt: bool = False,
+    passphrase: Optional[str] = None,
 ) -> bytes:
     """Export JWK as PEM/bin"""
 
diff --git a/src/cryptojwt/utils.py b/src/cryptojwt/utils.py
index d0c6d97f..b0619f74 100644
--- a/src/cryptojwt/utils.py
+++ b/src/cryptojwt/utils.py
@@ -158,8 +158,7 @@ def as_unicode(b):
 
 
 def bytes2str_conv(item):
-    """
-    """
+    """"""
     if isinstance(item, bytes):
         return item.decode("utf-8")
     elif item is None or isinstance(item, (str, int, bool)):
diff --git a/tests/test_01_simplejwt.py b/tests/test_01_simplejwt.py
index 02a944be..9d94a172 100644
--- a/tests/test_01_simplejwt.py
+++ b/tests/test_01_simplejwt.py
@@ -10,7 +10,10 @@ def _eq(l1, l2):
 def test_pack_jwt():
     _jwt = SimpleJWT(**{"alg": "none", "cty": "jwt"})
     jwt = _jwt.pack(
-        parts=[{"iss": "joe", "exp": 1300819380, "http://example.com/is_root": True}, "",]
+        parts=[
+            {"iss": "joe", "exp": 1300819380, "http://example.com/is_root": True},
+            "",
+        ]
     )
 
     p = jwt.split(".")
diff --git a/tests/test_02_jwk.py b/tests/test_02_jwk.py
index 02900600..a9307b8b 100644
--- a/tests/test_02_jwk.py
+++ b/tests/test_02_jwk.py
@@ -515,6 +515,9 @@ def test_key_from_jwk_dict_rsa():
     _key = key_from_jwk_dict(jwk)
     assert isinstance(_key, RSAKey)
     assert _key.has_private_key()
+    _key2 = RSAKey(**jwk)
+    assert isinstance(_key2, RSAKey)
+    assert _key2.has_private_key()
 
 
 def test_key_from_jwk_dict_ec():
@@ -707,7 +710,10 @@ def test_x5t_calculation():
 
 @pytest.mark.parametrize(
     "filename,key_type",
-    [("ec-public.pem", ec.EllipticCurvePublicKey), ("rsa-public.pem", rsa.RSAPublicKey),],
+    [
+        ("ec-public.pem", ec.EllipticCurvePublicKey),
+        ("rsa-public.pem", rsa.RSAPublicKey),
+    ],
 )
 def test_import_public_key_from_pem_file(filename, key_type):
     _file = full_path(filename)
diff --git a/tests/test_04_key_issuer.py b/tests/test_04_key_issuer.py
index 5e5fba7d..fedad978 100755
--- a/tests/test_04_key_issuer.py
+++ b/tests/test_04_key_issuer.py
@@ -221,7 +221,11 @@ def test_build_keyissuer_usage():
 
 def test_build_keyissuer_missing(tmpdir):
     keys = [
-        {"type": "RSA", "key": os.path.join(tmpdir.dirname, "missing_file"), "use": ["enc", "sig"],}
+        {
+            "type": "RSA",
+            "key": os.path.join(tmpdir.dirname, "missing_file"),
+            "use": ["enc", "sig"],
+        }
     ]
 
     key_issuer = build_keyissuer(keys)
@@ -239,7 +243,11 @@ def test_build_RSA_keyissuer_from_file(tmpdir):
 
 def test_build_EC_keyissuer_missing(tmpdir):
     keys = [
-        {"type": "EC", "key": os.path.join(tmpdir.dirname, "missing_file"), "use": ["enc", "sig"],}
+        {
+            "type": "EC",
+            "key": os.path.join(tmpdir.dirname, "missing_file"),
+            "use": ["enc", "sig"],
+        }
     ]
 
     key_issuer = build_keyissuer(keys)
@@ -616,7 +624,10 @@ def test_init_key_issuer_update():
 
     # New set of keys, JWKSs with keys and public written to file
     _keyissuer_1 = init_key_issuer(
-        private_path=PRIVATE_FILE, key_defs=KEYSPEC, public_path=PUBLIC_FILE, read_only=False,
+        private_path=PRIVATE_FILE,
+        key_defs=KEYSPEC,
+        public_path=PUBLIC_FILE,
+        read_only=False,
     )
     assert len(_keyissuer_1) == 2
 
@@ -646,7 +657,10 @@ def test_init_key_issuer_update():
     assert len(_keyissuer_3.get("sig", "EC")) == 1
 
     _keyissuer_4 = init_key_issuer(
-        private_path=PRIVATE_FILE, key_defs=KEYSPEC_2, public_path=PUBLIC_FILE, read_only=False,
+        private_path=PRIVATE_FILE,
+        key_defs=KEYSPEC_2,
+        public_path=PUBLIC_FILE,
+        read_only=False,
     )
 
     # Now it should
diff --git a/tests/test_04_key_jar.py b/tests/test_04_key_jar.py
index fcc19773..b31e5ba8 100755
--- a/tests/test_04_key_jar.py
+++ b/tests/test_04_key_jar.py
@@ -2,6 +2,7 @@
 import os
 import shutil
 import time
+import warnings
 
 import pytest
 
@@ -228,7 +229,11 @@ def test_build_keyjar_usage():
 
 def test_build_keyjar_missing(tmpdir):
     keys = [
-        {"type": "RSA", "key": os.path.join(tmpdir.dirname, "missing_file"), "use": ["enc", "sig"],}
+        {
+            "type": "RSA",
+            "key": os.path.join(tmpdir.dirname, "missing_file"),
+            "use": ["enc", "sig"],
+        }
     ]
 
     key_jar = build_keyjar(keys)
@@ -246,7 +251,11 @@ def test_build_RSA_keyjar_from_file(tmpdir):
 
 def test_build_EC_keyjar_missing(tmpdir):
     keys = [
-        {"type": "EC", "key": os.path.join(tmpdir.dirname, "missing_file"), "use": ["enc", "sig"],}
+        {
+            "type": "EC",
+            "key": os.path.join(tmpdir.dirname, "missing_file"),
+            "use": ["enc", "sig"],
+        }
     ]
 
     key_jar = build_keyjar(keys)
@@ -302,7 +311,8 @@ def test_items(self):
             ),
         )
         ks.add_kb(
-            "http://www.example.org", keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
+            "http://www.example.org",
+            keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
         )
 
         assert len(ks.items()) == 2
@@ -328,7 +338,8 @@ def test_issuer_extra_slash(self):
             ),
         )
         ks.add_kb(
-            "http://www.example.org", keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
+            "http://www.example.org",
+            keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
         )
 
         assert ks.get("sig", "RSA", "http://www.example.org/")
@@ -354,7 +365,8 @@ def test_issuer_missing_slash(self):
             ),
         )
         ks.add_kb(
-            "http://www.example.org/", keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
+            "http://www.example.org/",
+            keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
         )
 
         assert ks.get("sig", "RSA", "http://www.example.org")
@@ -380,7 +392,8 @@ def test_get_enc(self):
             ),
         )
         ks.add_kb(
-            "http://www.example.org/", keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
+            "http://www.example.org/",
+            keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
         )
 
         assert ks.get("enc", "oct")
@@ -406,7 +419,8 @@ def test_get_enc_not_mine(self):
             ),
         )
         ks.add_kb(
-            "http://www.example.org/", keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
+            "http://www.example.org/",
+            keybundle_from_local_file(RSAKEY, "der", ["ver", "sig"]),
         )
 
         assert ks.get("enc", "oct", "http://www.example.org/")
@@ -443,13 +457,20 @@ def test_no_use(self):
         assert enc_key != []
 
     @pytest.mark.network
+    @pytest.mark.skip("connect-op.herokuapp.com is broken")
     def test_provider(self):
         kj = KeyJar()
+        _url = "https://connect-op.herokuapp.com/jwks.json"
         kj.load_keys(
-            "https://connect-op.heroku.com", jwks_uri="https://connect-op.herokuapp.com/jwks.json",
+            "https://connect-op.heroku.com",
+            jwks_uri=_url,
         )
-
-        assert kj.get_issuer_keys("https://connect-op.heroku.com")[0].keys()
+        iss_keys = kj.get_issuer_keys("https://connect-op.heroku.com")
+        if not iss_keys:
+            _msg = "{} is not available at this moment!".format(_url)
+            warnings.warn(_msg)
+        else:
+            assert iss_kes[0].keys()
 
 
 def test_import_jwks():
@@ -961,7 +982,10 @@ def test_init_key_jar_update():
     assert len(_keyjar_3.get_signing_key("EC")) == 1
 
     _keyjar_4 = init_key_jar(
-        private_path=PRIVATE_FILE, key_defs=KEYSPEC_2, public_path=PUBLIC_FILE, read_only=False,
+        private_path=PRIVATE_FILE,
+        key_defs=KEYSPEC_2,
+        public_path=PUBLIC_FILE,
+        read_only=False,
     )
 
     # Now it should
diff --git a/tests/test_06_jws.py b/tests/test_06_jws.py
index 96b15ac2..c452e0b5 100644
--- a/tests/test_06_jws.py
+++ b/tests/test_06_jws.py
@@ -431,7 +431,8 @@ def test_jws_mm():
 
 
 @pytest.mark.parametrize(
-    "ec_func,alg", [(ec.SECP256R1, "ES256"), (ec.SECP384R1, "ES384"), (ec.SECP521R1, "ES512")],
+    "ec_func,alg",
+    [(ec.SECP256R1, "ES256"), (ec.SECP384R1, "ES384"), (ec.SECP521R1, "ES512")],
 )
 def test_signer_es(ec_func, alg):
     payload = "Please take a moment to register today"
@@ -706,7 +707,9 @@ def test_sign_json_dont_flatten_if_multiple_signatures():
     key = ECKey().load_key(P256())
     unprotected_headers = {"foo": "bar"}
     _jwt = JWS(msg="hello world", alg="ES256").sign_json(
-        headers=[(None, unprotected_headers), (None, {"abc": "xyz"})], keys=[key], flatten=True,
+        headers=[(None, unprotected_headers), (None, {"abc": "xyz"})],
+        keys=[key],
+        flatten=True,
     )
     assert "signatures" in json.loads(_jwt)
 
diff --git a/tests/test_09_jwt.py b/tests/test_09_jwt.py
index 26398575..71b019d5 100755
--- a/tests/test_09_jwt.py
+++ b/tests/test_09_jwt.py
@@ -26,10 +26,16 @@ def full_path(local_file):
 # k2 = import_private_rsa_key_from_file(full_path('size2048.key'))
 
 kb1 = KeyBundle(
-    source="file://{}".format(full_path("rsa.key")), fileformat="der", keyusage="sig", kid="1",
+    source="file://{}".format(full_path("rsa.key")),
+    fileformat="der",
+    keyusage="sig",
+    kid="1",
 )
 kb2 = KeyBundle(
-    source="file://{}".format(full_path("size2048.key")), fileformat="der", keyusage="enc", kid="2",
+    source="file://{}".format(full_path("size2048.key")),
+    fileformat="der",
+    keyusage="enc",
+    kid="2",
 )
 
 ALICE_KEY_JAR = KeyJar()
@@ -37,7 +43,10 @@ def full_path(local_file):
 ALICE_KEY_JAR.add_kb(ALICE, kb2)
 
 kb3 = KeyBundle(
-    source="file://{}".format(full_path("server.key")), fileformat="der", keyusage="enc", kid="3",
+    source="file://{}".format(full_path("server.key")),
+    fileformat="der",
+    keyusage="enc",
+    kid="3",
 )
 
 BOB_KEY_JAR = KeyJar()
diff --git a/tests/test_50_argument_alias.py b/tests/test_50_argument_alias.py
index 98b09479..746ab600 100644
--- a/tests/test_50_argument_alias.py
+++ b/tests/test_50_argument_alias.py
@@ -168,7 +168,10 @@ def test_init_key_jar_update():
     assert len(_keyjar_3.get_signing_key("EC")) == 1
 
     _keyjar_4 = init_key_jar(
-        private_path=PRIVATE_FILE, key_defs=KEYSPEC_2, public_path=PUBLIC_FILE, read_only=False,
+        private_path=PRIVATE_FILE,
+        key_defs=KEYSPEC_2,
+        public_path=PUBLIC_FILE,
+        read_only=False,
     )
 
     # Now it should
diff --git a/tox.ini b/tox.ini
index c3b44dff..def7f92e 100644
--- a/tox.ini
+++ b/tox.ini
@@ -4,13 +4,15 @@ envlist = py{36,37,38},quality
 [testenv]
 passenv = CI TRAVIS TRAVIS_*
 commands =
-    py.test --cov=cryptojwt tests/ {posargs}
+    py.test --cov=cryptojwt --isort --black {posargs}
     codecov
 extras = testing
 deps =
   codecov
+  pytest-black
   pytest-cov
   pytest-httpserver
+  pytest-isort
 
 [pep8]
 max-line-length=100
@@ -20,10 +22,10 @@ addopts = --color=yes
 markers = network
 
 [testenv:quality]
-# Black need python 3.6
-basepython = python3.6
+basepython = python3.8
 ignore_errors = True
 deps = twine
 extras = quality
 commands =
-    isort --recursive --diff --check-only src/ tests/
+    isort --check --diff src tests
+    black --check src tests