diff --git a/Makefile b/Makefile
index f10476e..a13df16 100644
--- a/Makefile
+++ b/Makefile
@@ -8,12 +8,6 @@ SHAREDIR := $(PREFIX)/share
 INCLUDEDIR := $(PREFIX)/include
 MANDIR := $(SHAREDIR)/man
 
-CC := cc
-AR := ar
-RANLIB := ranlib
-CFLAGS := 
-LDFLAGS := 
-
 Q := @
 
 all: build.zsh build/binary.zsh build/crystal.zsh build/header.zsh build/library.zsh build/livescript.zsh build/man.zsh build/moon.zsh build/ofile.zsh build/sass.zsh build/scdocman.zsh build/script.zsh build/sharedlib.zsh build/staticlib.zsh
@@ -320,10 +314,6 @@ help:
 	@echo '    - uninstall      Deinstalls the project.'
 	@echo ''
 	@echo 'CLI-modifiable variables:'
-	@echo '    - CC             ${CC}'
-	@echo '    - CFLAGS         ${CFLAGS}'
-	@echo '    - LDFLAGS        ${LDFLAGS}'
-	@echo '    - DESTDIR        ${DESTDIR}'
 	@echo '    - PREFIX         ${PREFIX}'
 	@echo '    - BINDIR         ${BINDIR}'
 	@echo '    - LIBDIR         ${LIBDIR}'
diff --git a/build.zsh.in b/build.zsh.in
index 2da108a..a92e4c4 100644
--- a/build.zsh.in
+++ b/build.zsh.in
@@ -75,6 +75,18 @@ function has {
 	return 1
 }
 
+function has_array_key {
+	local element="$1"
+
+	shift 1
+
+	for key value ($@) {
+		[[ "$key" == "$element" ]] && return 0
+	}
+
+	return 1
+}
+
 # Specialized helpers
 
 function get_distfiles {
@@ -211,13 +223,6 @@ function main {
 
 	write
 
-	write "CC := ${CC:-cc}"
-	write "AR := ${AR:-ar}"
-	write "RANLIB := ${RANLIB:-ranlib}"
-	write "CFLAGS := ${CFLAGS}"
-	write "LDFLAGS := ${LDFLAGS}"
-	write
-
 	write "Q := @"
 	write
 
@@ -444,15 +449,12 @@ function main {
 
 	write "	@echo ''"
 	write "	@echo '${fg_bold[white]}CLI-modifiable variables:${reset_color}'"
-	for VAR in CC CFLAGS LDFLAGS DESTDIR; do
+	for VAR __ in ${variables}; do
 		printf "	@echo '    - ${fg_bold[blue]}%-14s${fg[white]} \${$VAR}${reset_color}'\n" "$VAR" >> $Makefile
 	done
 	for VAR __ in ${prefixes}; do
 		printf "	@echo '    - ${fg_bold[blue]}%-14s${fg[white]} \${$VAR}${reset_color}'\n" "$VAR" >> $Makefile
 	done
-	for VAR __ in ${variables}; do
-		printf "	@echo '    - ${fg_bold[blue]}%-14s${fg[white]} \${$VAR}${reset_color}'\n" "$VAR" >> $Makefile
-	done
 
 	write "	@echo ''"
 	write "	@echo '${fg_bold[white]}Project targets: ${reset_color}'"
diff --git a/build/binary.zsh b/build/binary.zsh
index ac70975..b42577f 100644
--- a/build/binary.zsh
+++ b/build/binary.zsh
@@ -1,4 +1,18 @@
 
+function binary.prelude {
+	has_array_key CC $variables || \
+		variables+=(CC "cc")
+	has_array_key CXX $variables || \
+		variables+=(CXX "c++")
+	has_array_key LD $variables || \
+		variables+=(LD "\${CC}")
+
+	for variable in CFLAGS CXXFLAGS LDFLAGS; do
+		has_array_key $variable $variables || \
+			variables+=($variable " ")
+	done
+}
+
 function binary.build {
 	write -n "${target}:"
 	for i in ${src[@]}; do
diff --git a/build/crystal.zsh b/build/crystal.zsh
index 01077f7..80a025d 100644
--- a/build/crystal.zsh
+++ b/build/crystal.zsh
@@ -1,15 +1,6 @@
 
 function crystal.prelude {
-	local has_crflags=false
-
-	for variable value in ${variables[@]}; do
-		if [[ "$variable" == "CRFLAGS" ]]; then
-			has_crflags=true
-			break
-		fi
-	done
-
-	if ! $has_crflags; then
+	if ! has_array_key CRFLAGS; then
 		variables+=(CRFLAGS "--release")
 	fi
 }
diff --git a/build/library.zsh b/build/library.zsh
index 6ad88f9..5e4291b 100644
--- a/build/library.zsh
+++ b/build/library.zsh
@@ -1,4 +1,8 @@
 
+function library.prelude {
+	binary.prelude "$@"
+}
+
 function library.build {
 	write -n "${target}: ${target}.so ${target}.a $(dirdep $target)"
 	write
diff --git a/build/ofile.zsh b/build/ofile.zsh
index 1136e69..c8fe8ca 100644
--- a/build/ofile.zsh
+++ b/build/ofile.zsh
@@ -1,4 +1,8 @@
 
+function ofile.prelude {
+	binary.prelude "$@"
+}
+
 function ofile.build {
 	local dirname="$(dirname "$target")"
 	write -n "${target}: ${target%.o}.c $(dirdep $target "${target%.o}.c ${sources[$target]}" "${depends[@target]}")"