diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..b6f3827
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,265 @@
+NAME := avp
+
+# Required libraries.
+DEPS := libavcodec libavformat libavutil libswscale openal
+OBJS := \
+	src/avp/ai_sight.o \
+	src/avp/avpview.o \
+	src/avp/bh_agun.o \
+	src/avp/bh_ais.o \
+	src/avp/bh_alien.o \
+	src/avp/bh_binsw.o \
+	src/avp/bh_cable.o \
+	src/avp/bh_corpse.o \
+	src/avp/bh_deathvol.o \
+	src/avp/bh_debri.o \
+	src/avp/bh_dummy.o \
+	src/avp/bh_fan.o \
+	src/avp/bh_far.o \
+	src/avp/bh_fhug.o \
+	src/avp/bh_gener.o \
+	src/avp/bh_ldoor.o \
+	src/avp/bh_lift.o \
+	src/avp/bh_light.o \
+	src/avp/bh_lnksw.o \
+	src/avp/bh_ltfx.o \
+	src/avp/bh_marin.o \
+	src/avp/bh_mission.o \
+	src/avp/bh_near.o \
+	src/avp/bh_pargen.o \
+	src/avp/bh_plachier.o \
+	src/avp/bh_plift.o \
+	src/avp/bh_pred.o \
+	src/avp/bh_queen.o \
+	src/avp/bh_rubberduck.o \
+	src/avp/bh_selfdest.o \
+	src/avp/bh_snds.o \
+	src/avp/bh_spcl.o \
+	src/avp/bh_swdor.o \
+	src/avp/bh_track.o \
+	src/avp/bh_types.o \
+	src/avp/bh_videoscreen.o \
+	src/avp/bh_waypt.o \
+	src/avp/bh_weap.o \
+	src/avp/bh_xeno.o \
+	src/avp/bonusabilities.o \
+	src/avp/cconvars.o \
+	src/avp/cdtrackselection.o \
+	src/avp/cheatmodes.o \
+	src/avp/comp_map.o \
+	src/avp/comp_shp.o \
+	src/avp/consolelog.o \
+	src/avp/davehook.o \
+	src/avp/deaths.o \
+	src/avp/decal.o \
+	src/avp/detaillevels.o \
+	src/avp/dynamics.o \
+	src/avp/dynblock.o \
+	src/avp/equipmnt.o \
+	src/avp/extents.o \
+	src/avp/gamecmds.o \
+	src/avp/game.o \
+	src/avp/game_statistics.o \
+	src/avp/gamevars.o \
+	src/avp/hmodel.o \
+	src/avp/hud.o \
+	src/avp/inventry.o \
+	src/avp/language.o \
+	src/avp/lighting.o \
+	src/avp/load_shp.o \
+	src/avp/los.o \
+	src/avp/mempool.o \
+	src/avp/messagehistory.o \
+	src/avp/missions.o \
+	src/avp/movement.o \
+	src/avp/paintball.o \
+	src/avp/particle.o \
+	src/avp/pfarlocs.o \
+	src/avp/pheromon.o \
+	src/avp/player.o \
+	src/avp/pmove.o \
+	src/avp/psnd.o \
+	src/avp/psndproj.o \
+	src/avp/pvisible.o \
+	src/avp/savegame.o \
+	src/avp/scream.o \
+	src/avp/secstats.o \
+	src/avp/sfx.o \
+	src/avp/shapes/cube.o \
+	src/avp/stratdef.o \
+	src/avp/support/consbind.o \
+	src/avp/support/consbtch.o \
+	src/avp/support/coordstr.o \
+	src/avp/support/daemon.o \
+	src/avp/support/indexfnt.o \
+	src/avp/support/r2base.o \
+	src/avp/support/r2pos666.o \
+	src/avp/support/reflist.o \
+	src/avp/support/refobj.o \
+	src/avp/support/rentrntq.o \
+	src/avp/support/scstring.o \
+	src/avp/support/strtab.o \
+	src/avp/support/strutil.o \
+	src/avp/support/trig666.o \
+	src/avp/support/wrapstr.o \
+	src/avp/targeting.o \
+	src/avp/track.o \
+	src/avp/triggers.o \
+	src/avp/weapons.o \
+	src/avp/win95/avpchunk.o \
+	src/avp/win95/cheat.o \
+	src/avp/win95/chtcodes.o \
+	src/avp/win95/d3d_hud.o \
+	src/avp/win95/ddplat.o \
+	src/avp/win95/endianio.o \
+	src/avp/win95/ffread.o \
+	src/avp/win95/ffstdio.o \
+	src/avp/win95/frontend/avp_envinfo.o \
+	src/avp/win95/frontend/avp_intro.o \
+	src/avp/win95/frontend/avp_menudata.o \
+	src/avp/win95/frontend/avp_menus.o \
+	src/avp/win95/frontend/avp_mp_config.o \
+	src/avp/win95/frontend/avp_userprofile.o \
+	src/avp/win95/gadgets/ahudgadg.o \
+	src/avp/win95/gadgets/conscmnd.o \
+	src/avp/win95/gadgets/conssym.o \
+	src/avp/win95/gadgets/consvar.o \
+	src/avp/win95/gadgets/gadget.o \
+	src/avp/win95/gadgets/hudgadg.o \
+	src/avp/win95/gadgets/rootgadg.o \
+	src/avp/win95/gadgets/teletype.o \
+	src/avp/win95/gadgets/textexp.o \
+	src/avp/win95/gadgets/textin.o \
+	src/avp/win95/gadgets/t_ingadg.o \
+	src/avp/win95/gadgets/trepgadg.o \
+	src/avp/win95/gammacontrol.o \
+	src/avp/win95/hierplace.o \
+	src/avp/win95/iofocus.o \
+	src/avp/win95/jsndsup.o \
+	src/avp/win95/kzsort.o \
+	src/avp/win95/langplat.o \
+	src/avp/win95/modcmds.o \
+	src/avp/win95/npcsetup.o \
+	src/avp/win95/objsetup.o \
+	src/avp/win95/pathchnk.o \
+	src/avp/win95/platsup.o \
+	src/avp/win95/pldghost.o \
+	src/avp/win95/pldnet.o \
+	src/avp/win95/progress_bar.o \
+	src/avp/win95/projload.o \
+	src/avp/win95/scrshot.o \
+	src/avp/win95/strachnk.o \
+	src/avp/win95/system.o \
+	src/avp/win95/usr_io.o \
+	src/avp/win95/vision.o \
+	src/bink.o \
+	src/cdplayer.o \
+	src/fmv.o \
+	src/frustum.o \
+	src/kshape.o \
+	src/map.o \
+	src/mathline.o \
+	src/maths.o \
+	src/md5.o \
+	src/mem3dc.o \
+	src/mem3dcpp.o \
+	src/menus.o \
+	src/module.o \
+	src/morph.o \
+	src/net.o \
+	src/object.o \
+	src/oglfunc.o \
+	src/openal.o \
+	src/opengl.o \
+	src/shpanim.o \
+	src/sphere.o \
+	src/stubs.o \
+	src/tables.o \
+	src/vdb.o \
+	src/version.o \
+	src/win95/animchnk.o \
+	src/win95/animobs.o \
+	src/win95/awbmpld.o \
+	src/win95/awiffld.o \
+	src/win95/awpnmld.o \
+	src/win95/awtexld.o \
+	src/win95/bmpnames.o \
+	src/win95/chnkload.o \
+	src/win95/chnktexi.o \
+	src/win95/chnktype.o \
+	src/win95/chunk.o \
+	src/win95/chunkpal.o \
+	src/win95/db.o \
+	src/win95/debuglog.o \
+	src/win95/dummyobjectchunk.o \
+	src/win95/enumchnk.o \
+	src/win95/enumsch.o \
+	src/win95/envchunk.o \
+	src/win95/fail.o \
+	src/win95/fragchnk.o \
+	src/win95/gsprchnk.o \
+	src/win95/hierchnk.o \
+	src/win95/huffman.o \
+	src/win95/iff_ilbm.o \
+	src/win95/iff.o \
+	src/win95/ilbm_ext.o \
+	src/win95/io.o \
+	src/win95/list_tem.o \
+	src/win95/ltchunk.o \
+	src/win95/media.o \
+	src/win95/mishchnk.o \
+	src/win95/obchunk.o \
+	src/win95/oechunk.o \
+	src/win95/our_mem.o \
+	src/win95/plat_shp.o \
+	src/win95/plspecfn.o \
+	src/win95/shpchunk.o \
+	src/win95/sndchunk.o \
+	src/win95/sprchunk.o \
+	src/win95/string.o \
+	src/win95/texio.o \
+	src/win95/toolchnk.o \
+	src/win95/txioctrl.o \
+	src/win95/wpchunk.o \
+	src/win95/zsp.o \
+	src/files.o \
+	src/winapi.o
+
+INCLUDE := \
+	-Isrc \
+	-Isrc/include \
+	-Isrc/avp \
+	-Isrc/avp/support \
+	-Isrc/avp/win95 \
+	-Isrc/avp/win95/frontend \
+	-Isrc/avp/win95/gadgets \
+	-Isrc/win95
+
+# Optional libraries.
+ifdef USE_SDL1
+	DEPS += sdl
+	OBJS += src/main.o
+else
+	DEPS += sdl2
+	OBJS += src/main2.o
+endif
+
+ifdef USE_GLES2
+	DEPS += egl glesv2
+else
+	DEPS += gl
+endif
+
+CFLAGS += $(INCLUDE) $$(pkg-config --cflags $(DEPS))
+CXXFLAGS += $(INCLUDE) $$(pkg-config --cflags $(DEPS))
+LDFLAGS += $$(pkg-config --libs $(DEPS))
+
+$(NAME): $(OBJS)
+	$(CXX) $(OBJS) -o $(NAME) $(LDFLAGS)
+
+install: $(NAME)
+	install -d $(DESTDIR)/bin
+	install -m755 avp $(DESTDIR)/bin
+
+clean:
+	rm -f $(OBJS) $(NAME)
diff --git a/guix.scm b/guix.scm
index 300e833..32061c8 100644
--- a/guix.scm
+++ b/guix.scm
@@ -13,7 +13,7 @@
  (gnu packages pkg-config)
  (gnu packages sdl)
  (gnu packages video)
- (guix build-system cmake)
+ (guix build-system gnu)
  (guix build utils)
  (guix gexp)
  (guix git-download)
@@ -34,9 +34,13 @@
     (name "avp")
     (version (git-version source-dir))
     (source (local-file source-dir #:recursive? #t #:select? (git-predicate source-dir)))
-    (build-system cmake-build-system)
+    (build-system gnu-build-system)
     (arguments
-     (list #:tests? #f))
+     (list
+      #:tests? #f
+      #:make-flags #~(list "CC=gcc" (string-append "DESTDIR=" #$output))
+      #:phases
+      #~(modify-phases %standard-phases (delete 'configure))))
     (inputs
      (list ffmpeg mesa openal sdl2))
     (native-inputs