diff --git a/fuzzers/034-iob-stag/Makefile b/fuzzers/034-iob-stag/Makefile
index 1c2bc8da..4e3685f8 100644
--- a/fuzzers/034-iob-stag/Makefile
+++ b/fuzzers/034-iob-stag/Makefile
@@ -9,7 +9,7 @@ build/segbits_liob33.rdb: $(SPECIMENS_OK)
 	${XRAY_SEGMATCH} -c -1 -o build/segbits_liob33.rdb $(SEGDATAS)
 
 build/segbits_liob33.db: build/segbits_liob33.rdb
-	${XRAY_DBFIXUP} --db-root build --zero-db bits.dbf --seg-fn-in $^ --seg-fn-out $@
+	python3 ${XRAY_DIR}/utils/groupmask.py $^ $@
 	${XRAY_MASKMERGE} build/mask_liob33.db $(SEGDATAS)
 
 pushdb:
diff --git a/fuzzers/034-iob-stag/bits.dbf b/fuzzers/034-iob-stag/bits.dbf
deleted file mode 100644
index e69de29b..00000000
diff --git a/fuzzers/034-iob-stag/groups.grp b/fuzzers/034-iob-stag/groups.grp
new file mode 100644
index 00000000..f9cca48f
--- /dev/null
+++ b/fuzzers/034-iob-stag/groups.grp
@@ -0,0 +1 @@
+LIOB33.IOB_Y1.MACRO