move env to a nix flake

st/config.mk

@@ -1,29 +1,21 @@
 # st version
 VERSION = 0.9.3-odweta
 
-# Customize below to fit your system
-
 # paths
 PREFIX = /usr
 MANPREFIX = $(PREFIX)/share/man
 
-X11INC = /usr/X11R6/include
-X11LIB = /usr/X11R6/lib
-
+CC = cc
 PKG_CONFIG = pkg-config
 
-# includes and libs
-INCS = -I$(X11INC) \
-       `$(PKG_CONFIG) --cflags fontconfig` \
-       `$(PKG_CONFIG) --cflags freetype2`
-LIBS = -L$(X11LIB) -lm -lrt -lX11 -lutil -lXft \
-       `$(PKG_CONFIG) --libs fontconfig` \
-       `$(PKG_CONFIG) --libs freetype2`
+# compiler and linker flags
+X11INC = $(shell $(PKG_CONFIG) --cflags x11 xft xrandr xinerama fontconfig freetype2)
+X11LIB = $(shell $(PKG_CONFIG) --libs x11 xft xrandr xinerama fontconfig freetype2)
+
+INCS = $(X11INC)
+LIBS = $(X11LIB) -lm -lrt -lutil
 
-# flags
 STCPPFLAGS = -DVERSION=\"$(VERSION)\" -D_XOPEN_SOURCE=600
 STCFLAGS = $(INCS) $(STCPPFLAGS) $(CPPFLAGS) $(CFLAGS)
-STLDFLAGS = $(LIBS) $(LDFLAGS)
+STLDFLAGS = $(LDFLAGS) $(LIBS)
 
-# compiler and linker
-CC = cc