diff --git a/scripts/git-config.sh b/scripts/git-config.sh
index e15b718..48b1be5 100755
--- a/scripts/git-config.sh
+++ b/scripts/git-config.sh
@@ -1,6 +1,12 @@
 #!/bin/bash
 
-if [[ $1 == "-dry" ]]; then
+set -u
+
+ORIGIN=origin
+UPSTREAM=$ORIGIN
+MASTER=$UPSTREAM/master
+
+if [[ $# > 0 && "$1" == "-dry" ]]; then
   DRY=true
 else
   DRY=false
@@ -43,10 +49,11 @@ git_alias puf $'!sh -c \'git push -f origin $(git branch --show-current)\''
 
 git_alias rb rebase
 git_alias rbi "rebase -i --autosquash"
+git_alias rbim "rebase -i --autosquash $MASTER"
 git_alias rba "rebase --abort"
 git_alias rbc "rebase --continue"
 git_alias rbs "rebase --skip"
-git_alias rbom "rebase origin/master"
+git_alias rbm "rebase $MASTER"
 
 git_alias unstage "reset HEAD --"
 git_alias undo "reset --soft HEAD^"