Fix specialisation detection

I think

os/rebuild.sh

@@ -40,17 +40,31 @@ sudo nom build "$derivation^*" --no-link "$@"
 info "Showing diff"
 nvd diff "$(readlink -f /nix/var/nix/profiles/system)" "$toplevel"
 
-# Figure out specialisation
+info "Figuring current specialisation"
-specialisationArgs=()
+systemLink=
 currentSystem="$(readlink -f /run/current-system)"
-while read -r specialisation
+while read -r system
 do
-    if [ "$(readlink -f "/nix/var/nix/profiles/system/specialisation/$specialisation")" = "$currentSystem" ]
+    if [ "$(readlink -f "$system")" = "$currentSystem" ]
+    then
+        systemLink="$system"
+        break
+    fi
+done <<< "$(ls -d /nix/var/nix/profiles/system-*-link{,/specialisation/*})"
+
+specialisationArgs=()
+if [ -n "$systemLink" ]
+then
+    specialisation=$(echo "$systemLink" | cut -d/ -f8)
+    if [ -n "$specialisation" ]
     then
-        debug "Using specialisation: $specialisation"
         specialisationArgs=("--specialisation" "$specialisation")
     fi
-done <<< "$(ls /nix/var/nix/profiles/system/specialisation)"
+else
+    warning "Could not find link for $currentSystem, will switch to non-specialized system"
+fi
+
+
 
 # Apply
 confirm="n"