diff --git a/.gitignore b/.gitignore
index c6ad37e..f39f9ff 100644
--- a/.gitignore
+++ b/.gitignore
@@ -15,6 +15,11 @@
 # Editorconfig.
 !/.editorconfig
 
+# Parallel.
+!/.parallel/
+/.parallel/*
+!/.parallel/will-cite
+
 # Doc.
 !/.doc/
 !/.doc/**
diff --git a/.parallel/will-cite b/.parallel/will-cite
new file mode 100644
index 0000000..e69de29