diff --git a/host/Makefile b/host/Makefile
index 0cef5ab..dba6e9c 100644
--- a/host/Makefile
+++ b/host/Makefile
@@ -1,14 +1,23 @@
 HOST_BINARY := host.prg
 
 BUILD_DIR := ./build
+
+BUILD_TYPE ?= release
 SRC_DIR := ./src
 
+
 HOST_PRG := $(BUILD_DIR)/$(HOST_BINARY)
 PREVIEW_PRG := $(BUILD_DIR)/$(PREVIEW_BINARY)
 
 SRCS := $(shell find $(SRC_DIR) -name '*.s' -or -name '*.inc')
 TOPLEVEL := source.s
 
+ifeq ($(BUILD_TYPE), test)
+	TOPLEVEL := test.s
+endif
+
+
+
 CL := cl65
 
 CLFLAGS := -u __EXEHDR__ -t c64 -C c64-asm.cfg -l $(BUILD_DIR)/host.lst -Ln $(BUILD_DIR)/host.lbl
diff --git a/host/run.sh b/host/run.sh
index bbd27a5..378ea18 100755
--- a/host/run.sh
+++ b/host/run.sh
@@ -1,4 +1,4 @@
 # !/bin/bash
 killall x64sc
-make; \
+make BUILD_TYPE=test; \
 nohup flatpak run net.sf.VICE -windowypos 0 -windowxpos 960 -windowwidth 945 -windowheight 720 -moncommands build/host.lbl build/host.prg  </dev/null &>/dev/null &
diff --git a/host/src/source.s b/host/src/source.s
index 72f87e6..50d7fec 100644
--- a/host/src/source.s
+++ b/host/src/source.s
@@ -1,51 +1,39 @@
 ;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*-
+
+;; Source file for the project. Will compile inte a program that run programs
+;; injected through the game-port.
 .debuginfo      +       ; Generate debug info
-.org $080D
+.org $080D              ; Make listing file have the right offset.
 ;;Macros
 .include "macros/16aritmatic.s"
 ;;inc files
 .include "routines/memory/mem.inc"
 ;;Code to run
 .include "STARTUP.s"
+;; WIP, do not work.
 ;.include "dubbel_buffer/raster_irqs.s"
 
 .include "mainloop.s"
 .include "loader.s"
 
-;; Note that arithmatic tests may use upp all the memory and the compiler dont complain!
-;.include "routines/arithmatic/mult_test.s"
-;.include "routines/arithmatic/div_test.s"
-;.include "routines/arithmatic/div_test_zero.s"
-
-;.include "routines/circle/circle_test.s"
-;.include "routines/circle/circle_test_size.s"
-;.include "routines/circle/circle_test_position.s"
-;.include "routines/line/line_test.s"
-;.include "routines/line/line_test_extensive.s"
-;.include "routines/text/char_draw_test.s"
-;.include "routines/pixel/pixel_test.s"
-;.include "routines/memory/memcpy_test.s"
-;.include "routines/memory/memset_test.s"
-
-;.include "routines/triangle/triangle_test.s"
-exit:
-JMP exit
 .include "public.inc"
 .include "routines/line/line.s"
 .include "routines/circle/circle.s"
-.include "routines/triangle/triangle.s"
 .include "routines/pixel/pixel_draw.s"
 .include "routines/pixel/pixel_calc.s"
 .include "routines/pixel/misc_pixel.s"
 .include "routines/text/char_draw.s"
 .include "routines/memory/memset.s"
 .include "routines/memory/clear_screen.s"
-.include "routines/memory/memcpy.s"
 .include "routines/arithmatic/mult.s"
 .include "routines/arithmatic/div.s"
-
 .include "lookup_tables.s"
 
+;; WIP, will not work
+;.include "routines/triangle/triangle.s"
+;; Works but disabled because no use yet.
+;.include "routines/memory/memcpy.s"
+
 batch_userprog:
 .incbin "../userprog.bin"
 
diff --git a/host/src/test.s b/host/src/test.s
new file mode 100644
index 0000000..54fd2cb
--- /dev/null
+++ b/host/src/test.s
@@ -0,0 +1,51 @@
+;;; -*- Mode: asm; indent-tabs-mode: t; tab-width: 8 -*-
+.debuginfo      +       ; Generate debug info
+.org $080D
+;;Macros
+.include "macros/16aritmatic.s"
+;;inc files
+.include "routines/memory/mem.inc"
+;;Code to run
+.include "STARTUP.s"
+;; WIP, do not use.
+;.include "dubbel_buffer/raster_irqs.s"
+
+mainsetup:
+;; Note that arithmetic tests may use upp all the memory and the compiler don't complain!
+;.include "routines/arithmatic/mult_test.s"
+;.include "routines/arithmatic/div_test.s"
+.include "routines/arithmatic/div_test_zero.s"
+
+;.include "routines/circle/circle_test.s"
+;.include "routines/circle/circle_test_size.s"
+;.include "routines/circle/circle_test_position.s"
+;.include "routines/line/line_test.s"
+;.include "routines/line/line_test_extensive.s"
+;.include "routines/text/char_draw_test.s"
+;.include "routines/pixel/pixel_test.s"
+;.include "routines/memory/memcpy_test.s"
+;.include "routines/memory/memset_test.s"
+
+;.include "routines/triangle/triangle_test.s"
+exit:
+JMP exit
+.include "public.inc"
+;.include "routines/line/line.s"
+;.include "routines/circle/circle.s"
+;.include "routines/triangle/triangle.s"
+.include "routines/pixel/pixel_draw.s"
+;.include "routines/pixel/pixel_calc.s"
+;.include "routines/pixel/misc_pixel.s"
+;.include "routines/text/char_draw.s"
+.include "routines/memory/memset.s"
+.include "routines/memory/clear_screen.s"
+;.include "routines/memory/memcpy.s"
+;.include "routines/arithmatic/mult.s"
+.include "routines/arithmatic/div.s"
+
+.include "lookup_tables.s"
+
+batch_userprog:
+.incbin "../userprog.bin"
+
+.include "END.s"