diff --git a/.flake8 b/.flake8
new file mode 100644
index 0000000..e359058
--- /dev/null
+++ b/.flake8
@@ -0,0 +1,3 @@
+[flake8]
+ignore = E203, E241, W503, E501
+
diff --git a/.gitignore b/.gitignore
index 88ad5b2..3ba08e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,3 +15,4 @@ _*.c*
 *.dylib
 .vscode
 .pytest_cache/
+*.tags
diff --git a/noxfile.py b/noxfile.py
index f00073b..530f41f 100644
--- a/noxfile.py
+++ b/noxfile.py
@@ -9,21 +9,21 @@ PYTHON_FILES = [
 ]
 
 
-@nox.session
+@nox.session(reuse_venv=True)
 def lint(session):
     session.install("flake8", "black")
     session.run("flake8", *PYTHON_FILES)
     session.run("black", "--line-length=79", "--check", *PYTHON_FILES)
 
 
-@nox.session(python=["2.7", "3.7", "3.8", "3.9"])
+@nox.session(python=["2.7", "3.7", "3.8", "3.9"], reuse_venv=True)
 def test(session):
     session.install("pytest")
     session.install(".")
     session.run("pytest", "-v", "test")
 
 
-@nox.session
+@nox.session(reuse_venv=True)
 def gendoc(session):
     session.install("sphinx", "sphinx-rtd-theme")
     session.install(".")
diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..486bbe6
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,3 @@
+[tool.black]
+line-length = 79
+target-version = ['py27']