diff --git a/README.md b/README.md
index ab597e6cabf301a34c95683875f22a7aeb95efe0..ed8e17060a95ab0202c560458c2391bdef4f0713 100644
--- a/README.md
+++ b/README.md
@@ -34,14 +34,6 @@ and:
 pip install -r requirements.dev.txt
 ```
 
-## Cython
-
-Run:
-
-```bash
-python setup.py build_ext --inplace
-```
-
 ## Local vs. Cloud
 
 Almost all of the commands can be run locally or in the cloud. Simply add `--cloud` to the command to run it in the cloud. You will have to have [gsutil](https://cloud.google.com/storage/docs/gsutil) installed even when running locally.
diff --git a/requirements.dev.txt b/requirements.dev.txt
index ffdf74ec17089d0879a5b42bda05ba6bd7836fd9..e232dd5f8d69d12a5428e2bbbd9a4a6a1554a552 100644
--- a/requirements.dev.txt
+++ b/requirements.dev.txt
@@ -1,5 +1,4 @@
 flake8==3.7.7
-Cython==0.29.10
 nose==1.3.7
 pylint==1.9.4
 pytest==4.6.2