diff --git a/Makefile b/Makefile
index 270caaa..068fc57 100644
--- a/Makefile
+++ b/Makefile
@@ -66,7 +66,7 @@ SLIC3R_FLAGS=\
 	--skirts 3
 # --brim-width 10  #< combine with raft, if first layer fails to adhere well
 
-all: build/case.stl build/case.gcode build/case.sl1 build/case.ctb
+all: build/case.stl build/case.gcode build/case.sl1 build/case.ctb build/case.goo
 
 install:
 	mkdir -p $(SHAREDIR)
@@ -110,11 +110,17 @@ build/case.stl: main.py src/*.py
 %.sl1: %.stl
 	prusa-slicer --export-sla $<
 
-# .ctb: for Elegoo printers (requires `uvtools` package)
+# .ctb: for Gen 3 Elegoo printers (requires `uvtools` package)
 %.ctb: %.sl1
 	# XXX: UVtoolsCmd exits `1` on success ?? (what does it exit on failure? bleh)
 	UVtoolsCmd convert $< Chitubox $@  || test -f $@
 
+# .goo: for Gen 4+ Elegoo printers (requires `mslicer` package)
+%.goo: %.stl
+	# N.B. we rotate the model 90-degrees when slicing else it doesn't fit within print bounds.
+	# XXX: slicer's --rotation argument is radians; it may change to degrees in the future.
+	slicer --mesh $< --rotation 0,0,1.570796 $@
+
 readme: readme_files/pinephone_front_case_with_phone.png readme_files/pinephone_back_case_with_phone.png readme_files/pinephone_side_case_with_phone.png
 
 doc: readme build/web-viewer/index.html
diff --git a/README.md b/README.md
index 0740905..a4460bf 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,7 @@ you'll need a browser which supports webGL (e.g. chromium).
   - slic3r (if you want .gcode files, for FDM printers)
   - prusa-slicer (if you want .sl1 files, for resin printers)
   - uvtools (if you want .ctb files, for resin printers)
+  - mslicer (if you want .goo files, for later Elegoo printers)
 
 ## Building