diff --git a/definition-files/ubuntu/Singularity.ubuntu-18.04-cuda-10.1.168 b/definition-files/ubuntu/Singularity.ubuntu-18.04-cuda-10.1.168
index 25f4f59d6d92e40ff9066a13aed6f2e0024d0c66..22a50b7ac757df30af3de911bd80f4aecd963a24 100644
--- a/definition-files/ubuntu/Singularity.ubuntu-18.04-cuda-10.1.168
+++ b/definition-files/ubuntu/Singularity.ubuntu-18.04-cuda-10.1.168
@@ -1,5 +1,5 @@
 Bootstrap: shub
-From: mkandes/ubuntu:ubuntu-18.04
+From: mkandes/naked-singularity:ubuntu-18.04
 
 %labels
 
@@ -10,7 +10,7 @@ From: mkandes/ubuntu:ubuntu-18.04
     AUTHOR_NAME Marty Kandes
     AUTHOR_EMAIL mkandes@sdsc.edu
 
-    LAST_UPDATED 20200714
+    LAST_UPDATED 20201226
 
 %setup
 
diff --git a/definition-files/ubuntu/Singularity.ubuntu-18.04-mvapich-2.3.2 b/definition-files/ubuntu/Singularity.ubuntu-18.04-mvapich-2.3.2
index 2b3798fce6819897ffb03954c959ca0016157d59..6668668c722b04555bcbc33618dd9b8a981df189 100644
--- a/definition-files/ubuntu/Singularity.ubuntu-18.04-mvapich-2.3.2
+++ b/definition-files/ubuntu/Singularity.ubuntu-18.04-mvapich-2.3.2
@@ -1,5 +1,5 @@
 Bootstrap: shub
-From: mkandes/ubuntu:ubuntu-18.04
+From: mkandes/naked-singularity:ubuntu-18.04
 
 %labels
 
@@ -10,7 +10,7 @@ From: mkandes/ubuntu:ubuntu-18.04
     AUTHOR_NAME Marty Kandes
     AUTHOR_EMAIL mkandes@sdsc.edu
 
-    LAST_UPDATED 20200714
+    LAST_UPDATED 20201226
 
 %setup
 
diff --git a/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.4 b/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.4
index 6e84fe5869dda408a9c4c6b46e310be1022d1df7..458c1effa28a5bb87c01fb37540ca37b77d6f7fe 100644
--- a/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.4
+++ b/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.4
@@ -1,5 +1,5 @@
 Bootstrap: shub
-From: mkandes/ubuntu:ubuntu-18.04
+From: mkandes/naked-singularity:ubuntu-18.04
 
 %labels
 
@@ -10,7 +10,7 @@ From: mkandes/ubuntu:ubuntu-18.04
     AUTHOR_NAME Marty Kandes
     AUTHOR_EMAIL mkandes@sdsc.edu
 
-    LAST_UPDATED 20200809
+    LAST_UPDATED 20201226
 
 %setup
 
diff --git a/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.6 b/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.6
index dcc6fd0f5d2fc7cd2129b9489b47391a65ad5d43..bee2ff3d85a4ad304741ebb0f0c0e88da8a9329c 100644
--- a/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.6
+++ b/definition-files/ubuntu/Singularity.ubuntu-18.04-openmpi-3.1.6
@@ -1,5 +1,5 @@
 Bootstrap: shub
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+From: mkandes/naked-singularity:ubuntu-18.04
 
 %labels
 
@@ -10,7 +10,7 @@ From: mkandes/ubuntu:ubuntu-18.04
     AUTHOR_NAME Marty Kandes
     AUTHOR_EMAIL mkandes@sdsc.edu
 
-    LAST_UPDATED 20200809
+    LAST_UPDATED 20201226
 
 %setup