diff --git a/.bash_aliases/all b/.bash_aliases/all
index deaa29c..f967326 100644
--- a/.bash_aliases/all
+++ b/.bash_aliases/all
@@ -11,6 +11,7 @@ alias eal="nvim ~/.bash_aliasrc"
 alias ev="edit_editor_config"
 
 # Navigation
+
 alias ..="cd .."
 alias .2="cd ../.."
 alias .3="cd ../../.."
@@ -72,3 +73,33 @@ alias r="R"
 alias azerty="setxkbmap be"
 alias qwerty="setxkbmap us"
 alias cole="setxkbmap us -variant colemak"
+
+yarn() {
+  if [[ -f "package-lock.json" ]]; then
+    echo "WARNING: package-lock.json exists"
+    read -p "Are you sure you want to run yarn? [y/N] " -n 1 -r
+    echo
+    if [[ $REPLY =~ ^[Yy]$ ]]; then
+      command yarn "$@"
+    else
+      echo "Aborted"
+    fi
+  else
+    command yarn "$@"
+  fi
+}
+
+npm() {
+  if [[ -f "yarn.lock" ]]; then
+    echo "WARNING: yarn.lock exists"
+    read -p "Are you sure you want to run npm? [y/N] " -n 1 -r
+    echo
+    if [[ $REPLY =~ ^[Yy]$ ]]; then
+      command npm "$@"
+    else
+      echo "Aborted"
+    fi
+  else
+    command npm "$@"
+  fi
+}