diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 648c669e..bf0bc1cb 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -43,6 +43,12 @@ yarn
 yarn build
 ```
 
+To use multiple cores while building:
+
+```sh
+CIVET_THREADS=4 yarn build
+```
+
 ## Testing
 
 You can run all tests via