diff --git a/poetry.lock b/poetry.lock
index f4f871b..2fac3b4 100644
--- a/poetry.lock
+++ b/poetry.lock
@@ -1,5 +1,5 @@
 [[package]]
-category = "main"
+category = "dev"
 description = "A configurable sidebar-enabled Sphinx theme"
 name = "alabaster"
 optional = false
@@ -7,7 +7,7 @@ python-versions = "*"
 version = "0.7.12"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Internationalization utilities"
 name = "babel"
 optional = false
@@ -18,7 +18,7 @@ version = "2.8.0"
 pytz = ">=2015.7"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python package for providing Mozilla's CA Bundle."
 name = "certifi"
 optional = false
@@ -26,7 +26,7 @@ python-versions = "*"
 version = "2019.11.28"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Universal encoding detector for Python 2 and 3"
 name = "chardet"
 optional = false
@@ -34,7 +34,7 @@ python-versions = "*"
 version = "3.0.4"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Cross-platform colored terminal text."
 marker = "sys_platform == \"win32\""
 name = "colorama"
@@ -43,7 +43,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 version = "0.4.3"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Style checker for Sphinx (or other) RST documentation"
 name = "doc8"
 optional = false
@@ -58,7 +58,7 @@ six = "*"
 stevedore = "*"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Docutils -- Python Documentation Utilities"
 name = "docutils"
 optional = false
@@ -66,7 +66,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 version = "0.16"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Discover and load entry points from installed packages."
 name = "entrypoints"
 optional = false
@@ -74,7 +74,7 @@ python-versions = ">=2.7"
 version = "0.3"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "the modular source code checker: pep8, pyflakes and co"
 name = "flake8"
 optional = false
@@ -88,7 +88,7 @@ pycodestyle = ">=2.5.0,<2.6.0"
 pyflakes = ">=2.1.0,<2.2.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Internationalized Domain Names in Applications (IDNA)"
 name = "idna"
 optional = false
@@ -96,7 +96,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "2.9"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Getting image size from png/jpeg/jpeg2000/gif file"
 name = "imagesize"
 optional = false
@@ -104,7 +104,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "1.2.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "A very fast and expressive template engine."
 name = "jinja2"
 optional = false
@@ -118,7 +118,7 @@ MarkupSafe = ">=0.23"
 i18n = ["Babel (>=0.8)"]
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Safely add untrusted strings to HTML/XML markup."
 name = "markupsafe"
 optional = false
@@ -126,7 +126,7 @@ python-versions = ">=2.7,!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*"
 version = "1.1.1"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "McCabe checker, plugin for flake8"
 name = "mccabe"
 optional = false
@@ -134,7 +134,7 @@ python-versions = "*"
 version = "0.6.1"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Core utilities for Python packages"
 name = "packaging"
 optional = false
@@ -146,7 +146,7 @@ pyparsing = ">=2.0.2"
 six = "*"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python Build Reasonableness"
 name = "pbr"
 optional = false
@@ -154,7 +154,7 @@ python-versions = "*"
 version = "5.4.4"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python style guide checker"
 name = "pycodestyle"
 optional = false
@@ -162,7 +162,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "2.5.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "passive checker of Python programs"
 name = "pyflakes"
 optional = false
@@ -170,7 +170,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
 version = "2.1.1"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Pygments is a syntax highlighting package written in Python."
 name = "pygments"
 optional = false
@@ -178,7 +178,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
 version = "2.5.2"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python parsing module"
 name = "pyparsing"
 optional = false
@@ -186,7 +186,7 @@ python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*"
 version = "2.4.6"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "World timezone definitions, modern and historical"
 name = "pytz"
 optional = false
@@ -194,7 +194,7 @@ python-versions = "*"
 version = "2019.3"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python HTTP for Humans."
 name = "requests"
 optional = false
@@ -212,7 +212,7 @@ security = ["pyOpenSSL (>=0.14)", "cryptography (>=1.3.4)"]
 socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7)", "win-inet-pton"]
 
 [[package]]
-category = "main"
+category = "dev"
 description = "reStructuredText linter"
 name = "restructuredtext-lint"
 optional = false
@@ -223,7 +223,7 @@ version = "1.3.0"
 docutils = ">=0.11,<1.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python 2 and 3 compatibility utilities"
 name = "six"
 optional = false
@@ -231,7 +231,7 @@ python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*"
 version = "1.14.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "This package provides 26 stemmers for 25 languages generated from Snowball algorithms."
 name = "snowballstemmer"
 optional = false
@@ -239,7 +239,7 @@ python-versions = "*"
 version = "2.0.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Python documentation generator"
 name = "sphinx"
 optional = false
@@ -266,7 +266,7 @@ test = ["mock", "pytest", "pytest-cov", "html5lib", "flake8 (>=3.5.0)", "flake8-
 websupport = ["sqlalchemy (>=0.9)", "whoosh (>=2.0)"]
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Read the Docs theme for Sphinx"
 name = "sphinx-rtd-theme"
 optional = false
@@ -277,7 +277,7 @@ version = "0.4.3"
 sphinx = "*"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Sphinx \"contentui\" extension"
 name = "sphinxcontrib-contentui"
 optional = false
@@ -288,7 +288,7 @@ version = "0.2.2"
 Sphinx = ">=1.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Sphinx API for Web Apps"
 name = "sphinxcontrib-websupport"
 optional = false
@@ -300,7 +300,7 @@ lint = ["flake8"]
 test = ["pytest", "sqlalchemy", "whoosh", "sphinx"]
 
 [[package]]
-category = "main"
+category = "dev"
 description = "Manage dynamic plugins for Python applications"
 name = "stevedore"
 optional = false
@@ -312,7 +312,7 @@ pbr = ">=2.0.0,<2.1.0 || >2.1.0"
 six = ">=1.10.0"
 
 [[package]]
-category = "main"
+category = "dev"
 description = "HTTP library with thread-safe connection pooling, file post, and more."
 name = "urllib3"
 optional = false
@@ -325,7 +325,7 @@ secure = ["pyOpenSSL (>=0.14)", "cryptography (>=1.3.4)", "idna (>=2.0.0)", "cer
 socks = ["PySocks (>=1.5.6,<1.5.7 || >1.5.7,<2.0)"]
 
 [metadata]
-content-hash = "cfdc758b3080a5936922c4ed5c24bb32b1d729927a10c6bfd7d0a915f6d2f88f"
+content-hash = "419b4f06d75db3d41cdb67158a54fb7e2b5527bf1e59bd2671e65db6c8e6a321"
 python-versions = "^3.5"
 
 [metadata.files]
diff --git a/pyproject.toml b/pyproject.toml
index 2a02c2c..6323e25 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -7,13 +7,13 @@ license = "MIT"
 
 [tool.poetry.dependencies]
 python = "^3.5"
-sphinx = "==1.7.9"
-flake8 = "*"
-sphinx-rtd-theme = "==0.4.3"
-sphinxcontrib-contentui = "==0.2.2"
-doc8 = "*"
 
 [tool.poetry.dev-dependencies]
+doc8 = "*"
+flake8 = "*"
+sphinx = "==1.7.9"
+sphinx-rtd-theme = "==0.4.3"
+sphinxcontrib-contentui = "==0.2.2"
 
 [build-system]
 requires = ["poetry>=0.12"]