diff --git a/pyproject.toml b/pyproject.toml
index 9643a97b..9503a311 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -27,30 +27,29 @@ classifiers = [
 ]
 
 [tool.poetry.dependencies]
-python = "^3.6"
+python = "^3.5"
+blinker = "^1.4"
+docutils = "^0.16"
 feedgenerator = "^1.9"
 jinja2 = "~2.11"
 pygments = "~2.6.1"
-pytz = "^2019.1"
-blinker = "^1.4"
-unidecode = "^1.1"
 python-dateutil = "^2.8"
-docutils = "^0.15"
-markdown = {version = "~3.1.1", optional = true}
+pytz = "^2020.1"
+unidecode = "^1.1"
+markdown = {version = "~3.2.2", optional = true}
 
 [tool.poetry.dev-dependencies]
 BeautifulSoup4 = "^4.7"
 lxml = "^4.3"
-markdown = "~3.1.1"
+markdown = "~3.2.2"
 typogrify = "^2.0"
-sphinx = "=1.4.9"
+sphinx = "^3.0"
 sphinx_rtd_theme = "^0.4.3"
 livereload = "^2.6"
-mock = "^3.0"
-pytest = "~5.3.5"
+pytest = "^5.0"
 pytest-cov = "^2.8"
 pytest-pythonpath = "^0.7.3"
-pytest-sugar = "^0.9.2"
+pytest-sugar = "^0.9.3"
 pytest-xdist = "^1.31"
 tox = "^3.13"
 flake8 = "^3.7"