diff --git a/gitconfig.d/base.gitconfig b/gitconfig.d/base.gitconfig
index 212658d..3809aec 100644
--- a/gitconfig.d/base.gitconfig
+++ b/gitconfig.d/base.gitconfig
@@ -7,3 +7,8 @@
 	excludesfile = ~/.gitignore_global
 [pull]
 	rebase = true
+[alias]
+        undo = "!u() { \
+                NUM="${1:-1}"; \
+                git reset --soft HEAD~$1; \
+                };u"