diff --git a/.gitignore b/.gitignore
index 2c2c152..0f94d33 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,5 +1,6 @@
 Makefile
 **/__pycache__
+doc/build/doctrees/environment.pickle
 *.eps
 *.pdf
 *~