diff --git a/python3/bin/entrypoint.sh b/python3/bin/entrypoint.sh
index 2607c77..475df5d 100755
--- a/python3/bin/entrypoint.sh
+++ b/python3/bin/entrypoint.sh
@@ -1,4 +1,7 @@
 #!/usr/bin/env bash
+DEFAULT_UID=10000
+DEFAULT_GID=10000
+
 set -e
 
 if [[ -v DEBUG  ]]
@@ -6,6 +9,72 @@ then
     set -x
 fi
 
+# Function to create user and group if needed
+create_user_and_group() {
+    local uid="$1"
+    local gid="$2"
+    local username="openconext"
+    local groupname="openconext"
+
+    # Check if the group already exists (when gid is provided)
+    if [ -n "$gid" ]; then
+        if getent group "$groupname" > /dev/null 2>&1; then
+            # Group exists, check if GID matches
+            existing_gid=$(getent group "$groupname" | cut -d: -f3)
+            if [ "$existing_gid" != "$gid" ]; then
+                echo "ERROR: Group '$groupname' already exists with GID $existing_gid, but requested GID is $gid" >&2
+                echo "       Please recreate the container with the updated gid" >&2
+                exit 1
+            fi
+            echo "Group '$groupname' already exists with correct GID $gid" >&2
+        else
+            # Group doesn't exist, create it
+            echo "Creating group '$groupname' with GID $gid" >&2
+            groupadd -g "$gid" "$groupname"
+        fi
+    fi
+
+    # Check if the user already exists
+    if getent passwd "$username" > /dev/null 2>&1; then
+        # User exists, check if UID matches
+        existing_uid=$(getent passwd "$username" | cut -d: -f3)
+        if [ "$existing_uid" != "$uid" ]; then
+            echo "ERROR: User '$username' already exists with UID $existing_uid, but requested UID is $uid" >&2
+            echo "       Please recreate the container with the updated uid" >&2
+            exit 1
+        fi
+
+        # If GID is provided, check if user's primary group matches
+        if [ -n "$gid" ]; then
+            existing_primary_gid=$(getent passwd "$username" | cut -d: -f4)
+            if [ "$existing_primary_gid" != "$gid" ]; then
+                echo "ERROR: User '$username' already exists with primary GID $existing_primary_gid, but requested GID is $gid" >&2
+                echo "       Please recreate the container with the updated gid" >&2
+                exit 1
+            fi
+        fi
+
+        echo "User '$username' already exists with correct UID $uid" >&2
+    else
+        # User doesn't exist, create it
+        if [ -n "$gid" ]; then
+            echo "Creating user '$username' with UID $uid and GID $gid" >&2
+            useradd -M -u "$uid" -g "$gid" "$username"
+        else
+            echo "Creating user '$username' with UID $uid" >&2
+            useradd -M -u "$uid" "$username"
+        fi
+    fi
+
+    # Return the appropriate privilege dropping command
+    if [ -n "$gid" ]; then
+        echo "runuser --user=$username --group=$groupname -- "
+    else
+        echo "runuser --user=$username -- "
+    fi
+}
+
+
 # handle privilege dropping
 if [ $UID -ne 0 ]
 then
@@ -15,6 +84,10 @@ then
     exit 1
 fi
 
+# set up privilege dropping to user and group
+PRIVDROP=$(create_user_and_group "${RUNAS_UID:-$DEFAULT_UID}" "${RUNAS_GID:-$DEFAULT_GID}")
+echo "Dropping privileges to $($PRIVDROP id -u):$($PRIVDROP id -g)"
+
 # run custom scripts before dropping privileges
 echo "Running custom scripts in /container-init as root"
 if [ -d "/container-init" ]
@@ -23,24 +96,6 @@ then
     run-parts --verbose --regex '.*' "/container-init"
 fi
 
-# set up privilege dropping to user and group
-PRIVDROP=
-if [ -n "$RUNAS_UID" ]
-then
-    if [ -n "$RUNAS_GID" ]
-    then
-        echo "Switching to user $RUNAS_UID and group $RUNAS_GID"
-        groupadd -g $RUNAS_GID openconext
-        useradd -M -u $RUNAS_UID -g $RUNAS_GID openconext
-        PRIVDROP="runuser --user=openconext --group=openconext -- "
-    else
-        echo "Switching to user $RUNAS_UID"
-        useradd -M -u $RUNAS_UID openconext
-        PRIVDROP="runuser --user=openconext -- "
-    fi
-    echo "Dropping privileges to $($PRIVDROP id -u):$($PRIVDROP id -g)"
-fi
-
 # run custom scripts after dropping privileges
 echo "Running custom scripts in /container-init-post"
 if  [ -d "/container-init-post" ]
diff --git a/python3/test.sh b/python3/test.sh
new file mode 100755
index 0000000..4603002
--- /dev/null
+++ b/python3/test.sh
@@ -0,0 +1,21 @@
+#!/bin/bash
+echo "Build image"
+docker build -t python3:test . --no-cache
+
+echo
+echo "Remove old container"
+docker rm python3
+
+# With RUNAS_UID and RUNAS_GID
+echo
+echo "Run image with env"
+docker run --name python3 --env RUNAS_UID=10001 --env RUNAS_GID=10001 python3:test
+
+# Without RUNAS_UID and RUNAS_GID
+# echo
+# echo "Run without env"
+# docker run --name python3 python3:mve
+
+echo
+echo "Start container"
+docker start -i python3