diff --git a/src/environments/groupthm.pysty3 b/src/environments/groupthm.pysty3
index 79db9a1..7c9b389 100644
--- a/src/environments/groupthm.pysty3
+++ b/src/environments/groupthm.pysty3
@@ -6,10 +6,10 @@ __HEADER__(Grouping theorems for easier customization.)
 \RequirePackage{amsthm}
 \RequirePackage{thmtools}
 
-\NewHook { groupthm / prename }
-\NewHook { groupthm / postname }
-\NewHook { groupthm / mapname }
-\NewHook { groupthm / thmtools }
+\hook_new:n { groupthm / prename }
+\hook_new:n { groupthm / postname }
+\hook_new:n { groupthm / mapname }
+\hook_new:n { groupthm / thmtools }
 
 
 \newcounter{indocument}
@@ -88,22 +88,22 @@ __HEADER__(Grouping theorems for easier customization.)
 {
   \cs_new:cpn { group_use_#1: }
     {
-      \AddToHook { groupthm / prename } [ #1 ]
-      {
-          \tl_put_left:Nx \l_groupthm_prename_tl { #2 }
-      }
-      \AddToHook { groupthm / postname } [ #1 ]
-      {
-          \tl_put_right:Nx \l_groupthm_postname_tl { #3 }
-      }
-      \AddToHook { groupthm / mapname } [ #1 ]
-      {
-        \clist_put_right:Nn \l_groupthm_mapname_clist { #4 }
-      }
-      \AddToHook { groupthm / thmtools } [ #1 ]
-      {
-        \clist_put_right:Nn \l_groupthm_thmtools_clist { #5 }
-      }
+      \hook_gput_code:nnn { groupthm / prename } { #1 }
+        {
+            \tl_put_left:Nx \l_groupthm_prename_tl { #2 }
+        }
+      \hook_gput_code:nnn { groupthm / postname } { #1 }
+        {
+            \tl_put_right:Nx \l_groupthm_postname_tl { #3 }
+        }
+      \hook_gput_code:nnn { groupthm / mapname } { #1 }
+        {
+          \clist_put_right:Nn \l_groupthm_mapname_clist { #4 }
+        }
+      \hook_gput_code:nnn { groupthm / thmtools } { #1 }
+        {
+          \clist_put_right:Nn \l_groupthm_thmtools_clist { #5 }
+        }
     }
 }
 \cs_generate_variant:Nn \new_theorem_group:nnnnn { n V V V V }
@@ -154,10 +154,10 @@ __HEADER__(Grouping theorems for easier customization.)
   \clist_clear:N  \l_groupthm_mapname_clist
   \clist_set:Nn   \l_groupthm_thmtools_clist { #4 }
 
-  \RemoveFromHook { groupthm / prename  }[*]
-  \RemoveFromHook { groupthm / postname }[*]
-  \RemoveFromHook { groupthm / mapname  }[*]
-  \RemoveFromHook { groupthm / thmtools }[*]
+  \hook_gremove_code:nn { groupthm / prename  }{*}
+  \hook_gremove_code:nn { groupthm / postname }{*}
+  \hook_gremove_code:nn { groupthm / mapname  }{*}
+  \hook_gremove_code:nn { groupthm / thmtools }{*}
   
   \clist_map_function:nN { #2 } \group_use:n
   \hook_use:n { groupthm / prename }