diff --git a/requirements-dev.txt b/requirements-dev.txt
index c78656b..48e520d 100644
--- a/requirements-dev.txt
+++ b/requirements-dev.txt
@@ -20,6 +20,7 @@ mccabe==0.6.1             # via prospector, pylint
 multidict==3.3.2          # via aiohttp
 pep8-naming==0.4.1        # via prospector
 pip-tools==1.11.0
+ply==3.10
 prospector==0.12.7
 pycodestyle==2.0.0        # via prospector
 pydocstyle==2.1.1         # via prospector
diff --git a/requirements.in b/requirements.in
index b783bee..a4b5ba7 100644
--- a/requirements.in
+++ b/requirements.in
@@ -1,2 +1,3 @@
 discord.py
 Django
+ply
diff --git a/requirements.txt b/requirements.txt
index 1948d29..4d78867 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -10,5 +10,6 @@ chardet==3.0.4            # via aiohttp
 discord.py==0.16.12
 django==2.0.1
 multidict==3.3.2          # via aiohttp
+ply==3.10
 pytz==2017.3              # via django
 websockets==3.4           # via discord.py