diff --git a/pyproject.toml b/pyproject.toml
index 526cbee..b746f26 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -19,6 +19,7 @@ classifiers = [
 
 [tool.poetry.dependencies]
 python = "^3.5"
+cryptography = "2.7"
 pyOpenSSL = "~19"
 requests = "~2"
 
@@ -30,5 +31,5 @@ pytest-cov = "~2.7"
 responses = "~0.10"
 
 [build-system]
-requires = ["poetry>=0.12"]
+requires = ["poetry==1.0","cryptography==2.7","setuptools==51.0.0","wheel==0.35.1"]
 build-backend = "poetry.masonry.api"