diff --git a/shenvs/chrome.nix b/shenvs/chrome.nix
deleted file mode 100644
index 7c15d87..0000000
--- a/shenvs/chrome.nix
+++ /dev/null
@@ -1,5 +0,0 @@
-pkgs: {
-  paths = with pkgs; [
-    google-chrome
-  ];
-}
diff --git a/shenvs/config.nix b/shenvs/config.nix
index 9563aaa..2a40a4a 100644
--- a/shenvs/config.nix
+++ b/shenvs/config.nix
@@ -2,5 +2,6 @@ shenvs: {
   gcKeep = with shenvs; [
     armasm
     anpi
+    jupyter
   ];
 }
diff --git a/shenvs/mad.nix b/shenvs/mad.nix
new file mode 100644
index 0000000..2b7db52
--- /dev/null
+++ b/shenvs/mad.nix
@@ -0,0 +1,8 @@
+pkgs: {
+  paths = with pkgs; [
+    octave
+    (python39.withPackages ( packages: with packages; [
+      psycopg2	
+    ] )) 
+  ];
+}