diff --git a/.gitignore b/.gitignore
index 16b1b06..7981d18 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,3 +4,6 @@ docs/_build
 # Ignore irrelevant files from the Sublime Text editor
 *.sublime-workspace
 *.sublime-project
+
+# Ignore .hgignore for contributors using Mercurial.
+.hgignore