diff --git a/.flake8 b/.flake8
new file mode 100644
index 0000000..5376b8a
--- /dev/null
+++ b/.flake8
@@ -0,0 +1,4 @@
+[flake8]
+max-line-length = 80
+select = C,E,F,W,B,B950
+ignore = E203, E501, W503
diff --git a/.pre-commit-config.yaml b/.pre-commit-config.yaml
index 1729ddd..88d2704 100644
--- a/.pre-commit-config.yaml
+++ b/.pre-commit-config.yaml
@@ -10,6 +10,10 @@ repos:
   rev: 19.10b0
   hooks:
   - id: black
+- repo: https://gitlab.com/pycqa/flake8
+  rev: 3.7.9
+  hooks:
+  - id: flake8
 - repo: https://github.com/pre-commit/mirrors-mypy
   rev: v0.770
   hooks:
diff --git a/Makefile b/Makefile
index cb479ad..8c4fc17 100644
--- a/Makefile
+++ b/Makefile
@@ -2,7 +2,7 @@ POETRY ?= poetry
 PYTHON ?= $(POETRY) run python
 
 .PHONY: lint
-lint: mypy black
+lint: black flake8 mypy
 
 .PHONY: test
 test:
@@ -19,3 +19,7 @@ mypy:
 .PHONY: black
 black:
 	$(POETRY) run black .
+
+.PHONY: flake8
+flake8:
+	$(POETRY) run flake8 .
diff --git a/poetry.lock b/poetry.lock
index 33c4821..0c403b8 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -95,6 +95,14 @@ optional = false
 python-versions = "*"
 version = "0.3.0"
 
+[[package]]
+category = "dev"
+description = "Discover and load entry points from installed packages."
+name = "entrypoints"
+optional = false
+python-versions = ">=2.7"
+version = "0.3"
+
 [[package]]
 category = "dev"
 description = "A platform independent file lock."
@@ -104,6 +112,32 @@ optional = false
 python-versions = "*"
 version = "3.0.12"
 
+[[package]]
+category = "dev"
+description = "the modular source code checker: pep8, pyflakes and co"
+name = "flake8"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "3.7.9"
+
+[package.dependencies]
+entrypoints = ">=0.3.0,<0.4.0"
+mccabe = ">=0.6.0,<0.7.0"
+pycodestyle = ">=2.5.0,<2.6.0"
+pyflakes = ">=2.1.0,<2.2.0"
+
+[[package]]
+category = "dev"
+description = "A plugin for flake8 finding likely bugs and design problems in your program. Contains warnings that don't belong in pyflakes and pycodestyle."
+name = "flake8-bugbear"
+optional = false
+python-versions = ">=3.6"
+version = "20.1.4"
+
+[package.dependencies]
+attrs = ">=19.2.0"
+flake8 = ">=3.0.0"
+
 [[package]]
 category = "dev"
 description = "File identification library for Python"
@@ -153,6 +187,14 @@ version = ">=0.4"
 [package.extras]
 docs = ["sphinx", "rst.linker", "jaraco.packaging"]
 
+[[package]]
+category = "dev"
+description = "McCabe checker, plugin for flake8"
+name = "mccabe"
+optional = false
+python-versions = "*"
+version = "0.6.1"
+
 [[package]]
 category = "dev"
 description = "More routines for operating on iterables, beyond itertools"
@@ -188,7 +230,7 @@ description = "Utility library for gitignore style pattern matching of file path
 name = "pathspec"
 optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
-version = "0.7.0"
+version = "0.8.0"
 
 [[package]]
 category = "dev"
@@ -239,6 +281,22 @@ optional = false
 python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "1.8.1"
 
+[[package]]
+category = "dev"
+description = "Python style guide checker"
+name = "pycodestyle"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "2.5.0"
+
+[[package]]
+category = "dev"
+description = "passive checker of Python programs"
+name = "pyflakes"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "2.1.1"
+
 [[package]]
 category = "dev"
 description = "Python parsing module"
@@ -321,7 +379,7 @@ marker = "python_version >= \"3.6.1\" and python_version < \"4.0.0\""
 name = "virtualenv"
 optional = false
 python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,>=2.7"
-version = "20.0.16"
+version = "20.0.17"
 
 [package.dependencies]
 appdirs = ">=1.4.3,<2"
@@ -339,7 +397,7 @@ version = ">=1.0,<2"
 
 [package.extras]
 docs = ["sphinx (>=2.0.0,<3)", "sphinx-argparse (>=0.2.5,<1)", "sphinx-rtd-theme (>=0.4.3,<1)", "towncrier (>=19.9.0rc1)", "proselint (>=0.10.2,<1)"]
-testing = ["pytest (>=4.0.0,<6)", "coverage (>=4.5.1,<6)", "pytest-mock (>=2.0.0,<3)", "pytest-env (>=0.6.2,<1)", "pytest-timeout (>=1.3.4,<2)", "packaging (>=20.0)", "xonsh (>=0.9.13,<1)"]
+testing = ["pytest (>=4.0.0,<6)", "coverage (>=4.5.1,<6)", "pytest-mock (>=2.0.0,<3)", "pytest-env (>=0.6.2,<1)", "pytest-timeout (>=1.3.4,<2)", "packaging (>=20.0)", "xonsh (>=0.9.16,<1)"]
 
 [[package]]
 category = "dev"
@@ -363,7 +421,7 @@ docs = ["sphinx", "jaraco.packaging (>=3.2)", "rst.linker (>=1.9)"]
 testing = ["jaraco.itertools", "func-timeout"]
 
 [metadata]
-content-hash = "54c63a7523fa5d4fcfb42aebee8e7642e3143596cec113d764a51ccbf5acde76"
+content-hash = "4fe644f7a4afd82b031b88d45aae88527e3216e49825661881afd7a59f4741d7"
 python-versions = "^3.6"
 
 [metadata.files]
@@ -431,10 +489,22 @@ coverage = [
 distlib = [
     {file = "distlib-0.3.0.zip", hash = "sha256:2e166e231a26b36d6dfe35a48c4464346620f8645ed0ace01ee31822b288de21"},
 ]
+entrypoints = [
+    {file = "entrypoints-0.3-py2.py3-none-any.whl", hash = "sha256:589f874b313739ad35be6e0cd7efde2a4e9b6fea91edcc34e58ecbb8dbe56d19"},
+    {file = "entrypoints-0.3.tar.gz", hash = "sha256:c70dd71abe5a8c85e55e12c19bd91ccfeec11a6e99044204511f9ed547d48451"},
+]
 filelock = [
     {file = "filelock-3.0.12-py3-none-any.whl", hash = "sha256:929b7d63ec5b7d6b71b0fa5ac14e030b3f70b75747cef1b10da9b879fef15836"},
     {file = "filelock-3.0.12.tar.gz", hash = "sha256:18d82244ee114f543149c66a6e0c14e9c4f8a1044b5cdaadd0f82159d6a6ff59"},
 ]
+flake8 = [
+    {file = "flake8-3.7.9-py2.py3-none-any.whl", hash = "sha256:49356e766643ad15072a789a20915d3c91dc89fd313ccd71802303fd67e4deca"},
+    {file = "flake8-3.7.9.tar.gz", hash = "sha256:45681a117ecc81e870cbf1262835ae4af5e7a8b08e40b944a8a6e6b895914cfb"},
+]
+flake8-bugbear = [
+    {file = "flake8-bugbear-20.1.4.tar.gz", hash = "sha256:bd02e4b009fb153fe6072c31c52aeab5b133d508095befb2ffcf3b41c4823162"},
+    {file = "flake8_bugbear-20.1.4-py36.py37.py38-none-any.whl", hash = "sha256:a3ddc03ec28ba2296fc6f89444d1c946a6b76460f859795b35b77d4920a51b63"},
+]
 identify = [
     {file = "identify-1.4.14-py2.py3-none-any.whl", hash = "sha256:2bb8760d97d8df4408f4e805883dad26a2d076f04be92a10a3e43f09c6060742"},
     {file = "identify-1.4.14.tar.gz", hash = "sha256:faffea0fd8ec86bb146ac538ac350ed0c73908326426d387eded0bcc9d077522"},
@@ -447,6 +517,10 @@ importlib-resources = [
     {file = "importlib_resources-1.4.0-py2.py3-none-any.whl", hash = "sha256:dd98ceeef3f5ad2ef4cc287b8586da4ebad15877f351e9688987ad663a0a29b8"},
     {file = "importlib_resources-1.4.0.tar.gz", hash = "sha256:4019b6a9082d8ada9def02bece4a76b131518866790d58fdda0b5f8c603b36c2"},
 ]
+mccabe = [
+    {file = "mccabe-0.6.1-py2.py3-none-any.whl", hash = "sha256:ab8a6258860da4b6677da4bd2fe5dc2c659cff31b3ee4f7f5d64e79735b80d42"},
+    {file = "mccabe-0.6.1.tar.gz", hash = "sha256:dd8d182285a0fe56bace7f45b5e7d1a6ebcbf524e8f3bd87eb0f125271b8831f"},
+]
 more-itertools = [
     {file = "more-itertools-8.2.0.tar.gz", hash = "sha256:b1ddb932186d8a6ac451e1d95844b382f55e12686d51ca0c68b6f61f2ab7a507"},
     {file = "more_itertools-8.2.0-py3-none-any.whl", hash = "sha256:5dd8bcf33e5f9513ffa06d5ad33d78f31e1931ac9a18f33d37e77a180d393a7c"},
@@ -459,8 +533,8 @@ packaging = [
     {file = "packaging-20.3.tar.gz", hash = "sha256:3c292b474fda1671ec57d46d739d072bfd495a4f51ad01a055121d81e952b7a3"},
 ]
 pathspec = [
-    {file = "pathspec-0.7.0-py2.py3-none-any.whl", hash = "sha256:163b0632d4e31cef212976cf57b43d9fd6b0bac6e67c26015d611a647d5e7424"},
-    {file = "pathspec-0.7.0.tar.gz", hash = "sha256:562aa70af2e0d434367d9790ad37aed893de47f1693e4201fd1d3dca15d19b96"},
+    {file = "pathspec-0.8.0-py2.py3-none-any.whl", hash = "sha256:7d91249d21749788d07a2d0f94147accd8f845507400749ea19c1ec9054a12b0"},
+    {file = "pathspec-0.8.0.tar.gz", hash = "sha256:da45173eb3a6f2a5a487efba21f050af2b41948be6ab52b6a1e3ff22bb8b7061"},
 ]
 pluggy = [
     {file = "pluggy-0.13.1-py2.py3-none-any.whl", hash = "sha256:966c145cd83c96502c3c3868f50408687b38434af77734af1e9ca461a4081d2d"},
@@ -474,6 +548,14 @@ py = [
     {file = "py-1.8.1-py2.py3-none-any.whl", hash = "sha256:c20fdd83a5dbc0af9efd622bee9a5564e278f6380fffcacc43ba6f43db2813b0"},
     {file = "py-1.8.1.tar.gz", hash = "sha256:5e27081401262157467ad6e7f851b7aa402c5852dbcb3dae06768434de5752aa"},
 ]
+pycodestyle = [
+    {file = "pycodestyle-2.5.0-py2.py3-none-any.whl", hash = "sha256:95a2219d12372f05704562a14ec30bc76b05a5b297b21a5dfe3f6fac3491ae56"},
+    {file = "pycodestyle-2.5.0.tar.gz", hash = "sha256:e40a936c9a450ad81df37f549d676d127b1b66000a6c500caa2b085bc0ca976c"},
+]
+pyflakes = [
+    {file = "pyflakes-2.1.1-py2.py3-none-any.whl", hash = "sha256:17dbeb2e3f4d772725c777fabc446d5634d1038f234e77343108ce445ea69ce0"},
+    {file = "pyflakes-2.1.1.tar.gz", hash = "sha256:d976835886f8c5b31d47970ed689944a0262b5f3afa00a5a7b4dc81e5449f8a2"},
+]
 pyparsing = [
     {file = "pyparsing-2.4.7-py2.py3-none-any.whl", hash = "sha256:ef9d7589ef3c200abe66653d3f1ab1033c3c419ae9b9bdb1240a85b024efc88b"},
     {file = "pyparsing-2.4.7.tar.gz", hash = "sha256:c203ec8783bf771a155b207279b9bccb8dea02d8f0c9e5f8ead507bc3246ecc1"},
@@ -551,8 +633,8 @@ typed-ast = [
     {file = "typed_ast-1.4.1.tar.gz", hash = "sha256:8c8aaad94455178e3187ab22c8b01a3837f8ee50e09cf31f1ba129eb293ec30b"},
 ]
 virtualenv = [
-    {file = "virtualenv-20.0.16-py2.py3-none-any.whl", hash = "sha256:94f647e12d1e6ced2541b93215e51752aecbd1bbb18eb1816e2867f7532b1fe1"},
-    {file = "virtualenv-20.0.16.tar.gz", hash = "sha256:6ea131d41c477f6c4b7863948a9a54f7fa196854dbef73efbdff32b509f4d8bf"},
+    {file = "virtualenv-20.0.17-py2.py3-none-any.whl", hash = "sha256:00cfe8605fb97f5a59d52baab78e6070e72c12ca64f51151695407cc0eb8a431"},
+    {file = "virtualenv-20.0.17.tar.gz", hash = "sha256:c8364ec469084046c779c9a11ae6340094e8a0bf1d844330fc55c1cefe67c172"},
 ]
 wcwidth = [
     {file = "wcwidth-0.1.9-py2.py3-none-any.whl", hash = "sha256:cafe2186b3c009a04067022ce1dcd79cb38d8d65ee4f4791b8888d6599d1bbe1"},
diff --git a/pyproject.toml b/pyproject.toml
index 48f27c0..83f41e2 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,6 +19,8 @@ pre-commit = { version = "^2.2.0", python = "^3.6.1" }
 black = "^19.10b0"
 pytest = "^5.4.1"
 coverage = "^5.0.4"
+flake8 = "^3.7.9"
+flake8-bugbear = "^20.1.4"
 
 [build-system]
 requires = ["poetry>=0.12"]