diff --git a/stackrc b/stackrc
index 2dd56e8..ff82140 100644
--- a/stackrc
+++ b/stackrc
@@ -705,6 +705,53 @@
 
 # Following entries need to be last items in file
 
+# Compatibility bits required by other callers like Grenade
+
+# Old way was using SCREEN_LOGDIR to locate those logs and LOGFILE for the stack.sh trace log.
+# LOGFILE       SCREEN_LOGDIR       output
+# not set       not set             no log files
+# set           not set             stack.sh log to LOGFILE
+# not set       set                 screen logs to SCREEN_LOGDIR
+# set           set                 stack.sh log to LOGFILE, screen logs to SCREEN_LOGDIR
+
+# New way is LOGDIR for all logs and LOGFILE for stack.sh trace log, but if not fully-qualified will be in LOGDIR
+# LOGFILE       LOGDIR              output
+# not set       not set             (new) set LOGDIR from default
+# set           not set             stack.sh log to LOGFILE, (new) set LOGDIR from LOGFILE
+# not set       set                 screen logs to LOGDIR
+# set           set                 stack.sh log to LOGFILE, screen logs to LOGDIR
+
+# For compat, if SCREEN_LOGDIR is set, it will be used to create back-compat symlinks to the LOGDIR
+# symlinks to SCREEN_LOGDIR (compat)
+
+
+# Set up new logging defaults
+if [[ -z "${LOGDIR:-}" ]]; then
+    default_logdir=$DEST/logs
+    if [[ -z "${LOGFILE:-}" ]]; then
+        # Nothing is set, we need a default
+        LOGDIR="$default_logdir"
+    else
+        # Set default LOGDIR
+        LOGDIR="${LOGFILE%/*}"
+        logfile="${LOGFILE##*/}"
+        if [[ -z "$LOGDIR" || "$LOGDIR" == "$logfile" ]]; then
+            # LOGFILE had no path, set a default
+            LOGDIR="$default_logdir"
+        fi
+
+        # Check for duplication
+        if [[ "${SCREEN_LOGDIR:-}" == "${LOGDIR}" ]]; then
+            # We don't need the symlinks since it's the same directory
+            unset SCREEN_LOGDIR
+        fi
+    fi
+    unset default_logdir logfile
+fi
+
+# LOGDIR is always set at this point so it is not useful as a 'enable' for service logs
+# SCREEN_LOGDIR may be set, it is useful to enable the compat symlinks
+
 # Local variables:
 # mode: shell-script
 # End: