diff --git a/Cargo.toml b/Cargo.toml
new file mode 100644
index 0000000..6351443
--- /dev/null
+++ b/Cargo.toml
@@ -0,0 +1,30 @@
+[package]
+
+name = "rust-2048"
+version = "0.0.0"
+readme = "README.md"
+authors = ["coeuvre <coeuvre@gmail.com>"]
+tags = []
+
+[[bin]]
+
+name = "rust-2048"
+path = "src/main.rs"
+
+[dependencies.graphics]
+
+git = "https://github.com/pistondevelopers/rust-graphics"
+
+[dependencies.piston]
+
+git = "https://github.com/pistondevelopers/piston/"
+
+[dependencies.opengl_graphics]
+
+git = "https://github.com/pistondevelopers/opengl_graphics"
+
+[dependencies.sdl2_game_window]
+
+git = "https://github.com/pistondevelopers/sdl2_game_window"
+
+
diff --git a/Makefile b/Makefile
index 4a16777..723e7fa 100644
--- a/Makefile
+++ b/Makefile
@@ -27,6 +27,13 @@ SHELL := /bin/bash
 # The default make command.
 # Change this to 'lib' if you are building a library.
 DEFAULT = exe
+# The entry file of library source.
+# Change this to support multi-crate source structure.
+# For advanced usage, you can rename the file 'rust-empty.mk'
+# and call it with 'make -f rust-empty.mk <command>' from your Makefile.
+LIB_ENTRY_FILE = src/lib.rs
+# The entry file of executable source.
+EXE_ENTRY_FILE = src/main.rs
 
 EXAMPLE_FILES = examples/*.rs
 SOURCE_FILES = $(shell test -e src/ && find src -type f)
@@ -34,28 +41,29 @@ SOURCE_FILES = $(shell test -e src/ && find src -type f)
 COMPILER = rustc
 
 # For release:
-# COMPILER_FLAGS = -O
+  COMPILER_FLAGS = -O
 # For debugging:
-  COMPILER_FLAGS = -g
+# COMPILER_FLAGS = -g
 
 RUSTDOC = rustdoc
 
 # Extracts target from rustc.
-TARGET = $(shell rustc --version | awk "/host:/ { print \$$2 }")
+TARGET = $(shell rustc --version verbose 2> /dev/null | awk "/host:/ { print \$$2 }")
 # TARGET = x86_64-unknown-linux-gnu
 # TARGET = x86_64-apple-darwin
 
-TARGET_LIB_DIR = target/$(TARGET)/lib/
+TARGET_LIB_DIR = target/deps/
 
 # Ask 'rustc' the file name of the library and use a dummy name if the source has not been created yet.
 # The dummy file name is used to trigger the creation of the source first time.
 # Next time 'rustc' will return the right file name.
-RLIB_FILE = $(shell (rustc --crate-type=rlib --crate-file-name "src/lib.rs" 2> /dev/null) || (echo "dummy.rlib"))
+RLIB_FILE = $(shell (rustc --crate-type=rlib --crate-file-name "$(LIB_ENTRY_FILE)" 2> /dev/null) || (echo "dummy.rlib"))
 # You can't have quotes around paths because 'make' doesn't see it exists.
-RLIB = target/$(TARGET)/lib/$(RLIB_FILE)
-DYLIB_FILE = $(shell (rustc --crate-type=dylib --crate-file-name "src/lib.rs" 2> /dev/null) || (echo "dummy.dylib"))
-DYLIB = target/$(TARGET)/lib/$(DYLIB_FILE)
+RLIB = target/$(RLIB_FILE)
+DYLIB_FILE = $(shell (rustc --crate-type=dylib --crate-file-name "$(LIB_ENTRY_FILE)" 2> /dev/null) || (echo "dummy.dylib"))
+DYLIB = target/$(DYLIB_FILE)
 
+# Use 'VERBOSE=1' to echo all commands, for example 'make help VERBOSE=1'.
 ifdef VERBOSE
   Q :=
 else
@@ -65,35 +73,38 @@ endif
 all: $(DEFAULT)
 
 help:
-	$(Q)echo "--- rust-empty (0.3 005)" \
-	&& echo "make run               - Runs executable" \
-	&& echo "make exe               - Builds main executable" \
-	&& echo "make lib               - Both static and dynamic library" \
-	&& echo "make rlib              - Static library" \
-	&& echo "make dylib             - Dynamic library" \
-	&& echo "make test              - Tests library internally and externally" \
-	&& echo "make test-internal     - Tests library internally" \
-	&& echo "make test-external     - Tests library externally" \
-	&& echo "make bench             - Benchmarks library internally and externally" \
-	&& echo "make bench-internal    - Benchmarks library internally" \
-	&& echo "make bench-external    - Benchmarks library externally" \
-	&& echo "make doc               - Builds documentation for library" \
-	&& echo "make git-ignore        - Setup files to be ignored by Git" \
-	&& echo "make examples          - Builds examples" \
-	&& echo "make cargo-lite-exe    - Setup executable package" \
-	&& echo "make cargo-lite-lib    - Setup library package" \
-	&& echo "make cargo-exe         - EXPERIMENTAL: Setup executable package" \
-	&& echo "make cargo-lib         - EXPERIMENTAL: Setup library package" \
-	&& echo "make rust-ci-lib       - Setup Travis CI Rust library" \
-	&& echo "make rust-ci-exe       - Setup Travis CI Rust executable" \
-	&& echo "make rusti             - Setup 'rusti.sh' for interactive Rust" \
-	&& echo "make loc               - Count lines of code in src folder" \
-	&& echo "make nightly-install   - Installs Rust nightly built" \
-	&& echo "make nightly-uninstall - Uninstalls Rust nightly built" \
-	&& echo "make clean             - Deletes binaries and documentation." \
-	&& echo "make clear-project     - WARNING: Deletes project files except 'Makefile'" \
-	&& echo "make clear-git         - WARNING: Deletes Git setup" \
-	&& echo "make symlink-info      - Symlinked libraries dependency info"
+	$(Q)echo "--- rust-empty (0.6 003)"
+	$(Q)echo "make run               - Runs executable"
+	$(Q)echo "make exe               - Builds main executable"
+	$(Q)echo "make lib               - Both static and dynamic library"
+	$(Q)echo "make rlib              - Static library"
+	$(Q)echo "make dylib             - Dynamic library"
+	$(Q)echo "make test              - Tests library internally and externally"
+	$(Q)echo "make test-internal     - Tests library internally"
+	$(Q)echo "make test-external     - Tests library externally"
+	$(Q)echo "make bench             - Benchmarks library internally and externally"
+	$(Q)echo "make bench-internal    - Benchmarks library internally"
+	$(Q)echo "make bench-external    - Benchmarks library externally"
+	$(Q)echo "make doc               - Builds documentation for library"
+	$(Q)echo "make git-ignore        - Setup files to be ignored by Git"
+	$(Q)echo "make examples          - Builds examples"
+	$(Q)echo "make cargo-lite-exe    - Setup executable package"
+	$(Q)echo "make cargo-lite-lib    - Setup library package"
+	$(Q)echo "make cargo-exe         - Setup executable package"
+	$(Q)echo "make cargo-lib         - Setup library package"
+	$(Q)echo "make rust-ci-lib       - Setup Travis CI Rust library"
+	$(Q)echo "make rust-ci-exe       - Setup Travis CI Rust executable"
+	$(Q)echo "make rusti             - Setup 'rusti.sh' for interactive Rust"
+	$(Q)echo "make watch             - Setup 'watch.sh' for compilation on save"
+	$(Q)echo "make loc               - Count lines of code in src folder"
+	$(Q)echo "make nightly-install   - Installs Rust nightly build"
+	$(Q)echo "make nightly-uninstall - Uninstalls Rust nightly build"
+	$(Q)echo "make clean             - Deletes binaries and documentation."
+	$(Q)echo "make clear-project     - WARNING: Deletes project files except 'Makefile'"
+	$(Q)echo "make clear-git         - WARNING: Deletes Git setup"
+	$(Q)echo "make symlink-build     - Creates a script for building dependencies"
+	$(Q)echo "make symlink-info      - Symlinked libraries dependency info"
+	$(Q)echo "make target-dir        - Creates directory for current target"
 
 .PHONY: \
 		bench \
@@ -113,10 +124,13 @@ help:
 		rusti \
 		rust-ci-lib \
 		rust-ci-exe \
+		symlink-build \
 		symlink-info \
+		target-dir \
 		test \
 		test-internal \
-		test-external
+	    test-external \
+		watch
 
 nightly-install:
 	$(Q)cd ~ \
@@ -144,31 +158,31 @@ nightly-uninstall:
 		fi \
 	)
 
-cargo-lite-exe: src/main.rs
+cargo-lite-exe: $(EXE_ENTRY_FILE)
 	$(Q)( \
 		test -e cargo-lite.conf \
 		&& echo "--- The file 'cargo-lite.conf' already exists" \
 	) \
 	|| \
 	( \
-		echo -e "deps = [\n]\n\n[build]\ncrate_root = \"src/main.rs\"\nrustc_args = []\n" > cargo-lite.conf \
+		echo -e "deps = [\n]\n\n[build]\ncrate_root = \"$(EXE_ENTRY_FILE)\"\nrustc_args = []\n" > cargo-lite.conf \
 		&& echo "--- Created 'cargo-lite.conf' for executable" \
 		&& cat cargo-lite.conf \
 	)
 
-cargo-lite-lib: src/lib.rs
+cargo-lite-lib: $(LIB_ENTRY_FILE)
 	$(Q)( \
 		test -e cargo-lite.conf \
 		&& echo "--- The file 'cargo-lite.conf' already exists" \
 	) \
 	|| \
 	( \
-		echo -e "deps = [\n]\n\n[build]\ncrate_root = \"src/lib.rs\"\ncrate_type = \"library\"\nrustc_args = []\n" > cargo-lite.conf \
+		echo -e "deps = [\n]\n\n[build]\ncrate_root = \"$(LIB_ENTRY_FILE)\"\ncrate_type = \"library\"\nrustc_args = []\n" > cargo-lite.conf \
 		&& echo "--- Created 'cargo-lite.conf' for library" \
 		&& cat cargo-lite.conf \
 	)
 
-cargo-exe: src/main.rs
+cargo-exe: $(EXE_ENTRY_FILE)
 	$(Q)( \
 		test -e Cargo.toml \
 		&& echo "--- The file 'Cargo.toml' already exists" \
@@ -177,12 +191,12 @@ cargo-exe: src/main.rs
 	( \
 		name=$${PWD##/*/} ; \
 		readme=$$((test -e README.md && echo -e "readme = \"README.md\"") || ("")) ; \
-		echo -e "[project]\n\nname = \"$$name\"\nversion = \"0.0\"\n$$readme\nauthors = [\"Your Name <your@email.com>\"]\ntags = []\n\n[[bin]]\n\nname = \"$$name\"\npath = \"bin/main.rs\"\n" > Cargo.toml \
+		echo -e "[package]\n\nname = \"$$name\"\nversion = \"0.0.0\"\n$$readme\nauthors = [\"Your Name <your@email.com>\"]\ntags = []\n\n[[bin]]\n\nname = \"$$name\"\npath = \"$(EXE_ENTRY_FILE)\"\n" > Cargo.toml \
 		&& echo "--- Created 'Cargo.toml' for executable" \
 		&& cat Cargo.toml \
 	)
 
-cargo-lib: src/main.rs
+cargo-lib: $(LIB_ENTRY_FILE)
 	$(Q)( \
 		test -e Cargo.toml \
 		&& echo "--- The file 'Cargo.toml' already exists" \
@@ -191,47 +205,49 @@ cargo-lib: src/main.rs
 	( \
 		name=$${PWD##/*/} ; \
 		readme=$$((test -e README.md && echo -e "readme = \"README.md\"") || ("")) ; \
-		echo -e "[project]\n\nname = \"$$name\"\nversion = \"0.0\"\n$$readme\nauthors = [\"Your Name <your@email.com>\"]\ntags = []\n\n[[lib]]\n\nname = \"$$name\"\npath = \"bin/lib.rs\"\n" > Cargo.toml \
+		echo -e "[package]\n\nname = \"$$name\"\nversion = \"0.0.0\"\n$$readme\nauthors = [\"Your Name <your@email.com>\"]\ntags = []\n\n[[lib]]\n\nname = \"$$name\"\npath = \"$(LIB_ENTRY_FILE)\"\n" > Cargo.toml \
 		&& echo "--- Created 'Cargo.toml' for executable" \
 		&& cat Cargo.toml \
 	)
 
-rust-ci-lib: src/lib.rs
+rust-ci-lib: $(LIB_ENTRY_FILE)
 	$(Q)( \
 		test -e .travis.yml \
 		&& echo "--- The file '.travis.yml' already exists" \
 	) \
 	|| \
 	( \
-		echo -e "before_install:\n\t- yes | sudo add-apt-repository ppa:hansjorg/rust\n\t- sudo apt-get update\ninstall:\n\t- sudo apt-get install rust-nightly\nscript:\n\t- make lib\n" > .travis.yml \
+		echo -e "install:\n  - wget http://static.rust-lang.org/dist/rust-nightly-x86_64-unknown-linux-gnu.tar.gz -O - | sudo tar zxf - --strip-components 1 -C /usr/local\nscript:\n  - make lib\n" > .travis.yml \
 		&& echo "--- Created '.travis.yml' for library" \
 		&& cat .travis.yml \
 	)
 
-rust-ci-exe: src/main.rs
+rust-ci-exe: $(EXE_ENTRY_FILE)
 	$(Q)( \
 		test -e .travis.yml \
 		&& echo "--- The file '.travis.yml' already exists" \
 	) \
 	|| \
 	( \
-		echo -e "before_install:\n\t- yes | sudo add-apt-repository ppa:hansjorg/rust\n\t- sudo apt-get update\ninstall:\n\t- sudo apt-get install rust-nightly\nscript:\n\t- make exe\n" > .travis.yml \
+		echo -e "install:\n  - wget http://static.rust-lang.org/dist/rust-nightly-x86_64-unknown-linux-gnu.tar.gz -O - | sudo tar zxf - --strip-components 1 -C /usr/local\nscript:\n  - make exe\n" > .travis.yml \
 		&& echo "--- Created '.travis.yml' for executable" \
 		&& cat .travis.yml \
 	)
 
 doc: $(SOURCE_FILES) | src/
-	$(Q)$(RUSTDOC) src/lib.rs -L "target/$(TARGET)/lib" \
+	$(Q)$(RUSTDOC) $(LIB_ENTRY_FILE) -L "$(TARGET_LIB_DIR)" \
 	&& echo "--- Built documentation"
 
 run: exe
 	$(Q)cd bin/ \
 	&& ./main
 
+target-dir: $(TARGET_LIB_DIR)
+
 exe: bin/main | $(TARGET_LIB_DIR)
 
-bin/main: $(SOURCE_FILES) | bin/ src/main.rs
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) src/main.rs -o bin/main -L "target/$(TARGET)/lib" \
+bin/main: $(SOURCE_FILES) | bin/ $(EXE_ENTRY_FILE)
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) $(EXE_ENTRY_FILE) -o bin/main -L "$(TARGET_LIB_DIR)" -L "target" \
 	&& echo "--- Built executable" \
 	&& echo "--- Type 'make run' to run executable"
 
@@ -244,7 +260,7 @@ test-external: bin/test-external
 	&& ./test-external
 
 bin/test-external: $(SOURCE_FILES) | rlib bin/ src/test.rs
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --test src/test.rs -o bin/test-external -L "target/$(TARGET)/lib" \
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --test src/test.rs -o bin/test-external -L "$(TARGET_LIB_DIR)" -L "target" \
 	&& echo "--- Built external test runner"
 
 test-internal: bin/test-internal
@@ -252,7 +268,7 @@ test-internal: bin/test-internal
 	&& ./test-internal
 
 bin/test-internal: $(SOURCE_FILES) | rlib src/ bin/
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --test src/lib.rs -o bin/test-internal -L "target/$(TARGET)/lib" \
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --test $(LIB_ENTRY_FILE) -o bin/test-internal -L "$(TARGET_LIB_DIR)" -L "target" \
 	&& echo "--- Built internal test runner"
 
 bench: bench-internal bench-external
@@ -268,23 +284,23 @@ lib: rlib dylib
 
 rlib: $(RLIB)
 
-$(RLIB): $(SOURCE_FILES) | src/lib.rs $(TARGET_LIB_DIR)
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --crate-type=rlib src/lib.rs -L "target/$(TARGET)/lib" --out-dir "target/$(TARGET)/lib/" \
+$(RLIB): $(SOURCE_FILES) | $(LIB_ENTRY_FILE) $(TARGET_LIB_DIR)
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --crate-type=rlib $(LIB_ENTRY_FILE) -L "$(TARGET_LIB_DIR)" --out-dir "target" \
 	&& echo "--- Built rlib"
 
 dylib: $(DYLIB)
 
-$(DYLIB): $(SOURCE_FILES) | src/lib.rs $(TARGET_LIB_DIR)
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --crate-type=dylib src/lib.rs -L "target/$(TARGET)/lib" --out-dir "target/$(TARGET)/lib/" \
+$(DYLIB): $(SOURCE_FILES) | $(LIB_ENTRY_FILE) $(TARGET_LIB_DIR)
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) --crate-type=dylib $(LIB_ENTRY_FILE) -L "$(TARGET_LIB_DIR)" --out-dir "target/" \
 	&& echo "--- Built dylib"
 
-bin:
+bin/:
 	$(Q)mkdir -p bin
 
 $(TARGET_LIB_DIR):
 	$(Q)mkdir -p $(TARGET_LIB_DIR)
 
-src:
+src/:
 	$(Q)mkdir -p src
 
 examples-dir:
@@ -306,7 +322,7 @@ git-ignore:
 	) \
 	|| \
 	( \
-		echo -e ".DS_Store\n*~\n*#\n*.o\n*.so\n*.swp\n*.dylib\n*.dSYM\n*.dll\n*.rlib\n*.dummy\n*.exe\n*-test\n/bin/main\n/bin/test-internal\n/bin/test-external\n/doc/\n/target/\n/build/\n/.rust/\nrusti.sh\n" > .gitignore \
+		echo -e ".DS_Store\n*~\n*#\n*.o\n*.so\n*.swp\n*.dylib\n*.dSYM\n*.dll\n*.rlib\n*.dummy\n*.exe\n*-test\n/bin/main\n/bin/test-internal\n/bin/test-external\n/doc/\n/target/\n/build/\n/.rust/\nrusti.sh\nwatch.sh\n/examples/**\n!/examples/*.rs\n!/examples/assets/" > .gitignore \
 		&& echo "--- Created '.gitignore' for git" \
 		&& cat .gitignore \
 	)
@@ -314,14 +330,14 @@ git-ignore:
 examples: $(EXAMPLE_FILES)
 
 $(EXAMPLE_FILES): lib examples-dir
-	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) $@ -L "target/$(TARGET)/lib" --out-dir examples/ \
-	&& echo "--- Built examples"
+	$(Q)$(COMPILER) --target "$(TARGET)" $(COMPILER_FLAGS) $@ -L "$(TARGET_LIB_DIR)" -L "target" --out-dir examples/ \
+	&& echo "--- Built '$@' (make $@)"
 
-src/main.rs: | src/
-	$(Q)test -e src/main.rs \
+$(EXE_ENTRY_FILE): | src/
+	$(Q)test -e $(EXE_ENTRY_FILE) \
 	|| \
 	( \
-		echo -e "fn main() {\n\tprintln!(\"Hello world!\");\n}" > src/main.rs \
+		echo -e "fn main() {\n\tprintln!(\"Hello world!\");\n}" > $(EXE_ENTRY_FILE) \
 	)
 
 src/test.rs: | src/
@@ -331,11 +347,11 @@ src/test.rs: | src/
 		touch src/test.rs \
 	)
 
-src/lib.rs: | src/
-	$(Q)test -e src/lib.rs \
+$(LIB_ENTRY_FILE): | src/
+	$(Q)test -e $(LIB_ENTRY_FILE) \
 	|| \
 	( \
-		echo -e "#![crate_id = \"\"]\n#![deny(missing_doc)]\n\n//! Documentation goes here.\n" > src/lib.rs \
+		echo -e "#![crate_id = \"\"]\n#![deny(missing_doc)]\n\n//! Documentation goes here.\n" > $(LIB_ENTRY_FILE) \
 	)
 
 clean:
@@ -350,8 +366,10 @@ clean:
 clear-project:
 	$(Q)rm -f ".symlink-info"
 	$(Q)rm -f "cargo-lite.conf"
+	$(Q)rm -f "Cargo.toml"
 	$(Q)rm -f ".travis.yml"
 	$(Q)rm -f "rusti.sh"
+	$(Q)rm -f "watch.sh"
 	$(Q)rm -rf "target/"
 	$(Q)rm -rf "src/"
 	$(Q)rm -rf "bin/"
@@ -378,7 +396,7 @@ while true; do
   echo -n "> "
   read line
   TMP="`mktemp r.XXXXXX`"
-  $(COMPILER) - -o $$TMP -L "target/$(TARGET)/lib/" <<EOF
+  $(COMPILER) - -o $$TMP -L "$(TARGET_LIB_DIR)" <<EOF
   #![feature(globs, macro_rules, phase, struct_variant)]
   extern crate arena;
   extern crate collections;
@@ -392,6 +410,8 @@ while true; do
   extern crate native;
   extern crate num;
   extern crate rand;
+  extern crate regex;
+  #[phase(syntax)] extern crate regex_macros;
   extern crate rustc;
   extern crate rustdoc;
   extern crate rustuv;
@@ -430,6 +450,206 @@ rusti: $(TARGET_LIB_DIR)
 		&& echo "--- Type './rusti.sh' to start interactive Rust" \
 	)
 
+# borrowed from http://stackoverflow.com/q/649246/1256624
+define WATCH_SCRIPT
+#!/bin/bash
+
+#written by zzmp
+
+# This script will recompile a rust project using `make`
+# every time something in the specified directory changes.
+
+# Watch files in infinite loop
+watch () {
+  UNAME=$$(uname)
+  if [ -e "$$2" ]; then
+    echo "Watching files in $$2.."
+    CTIME=$$(date "+%s")
+    while :; do
+      sleep 1
+      for f in `find $$2 -type f -name "*.rs"`; do
+        if [[ $$UNAME == "Darwin" ]]; then
+          st_mtime=$$(stat -f "%m" "$$f")
+        elif [[ $$UNAME == "FreeBSD" ]]; then
+          st_mtime=$$(stat -f "%m" "$$f")
+        else
+          st_mtime=$$(stat -c "%Y" "$$f")
+        fi
+        if [ $$st_mtime -gt $$CTIME ]; then
+          CTIME=$$(date "+%s")
+          echo "~~~ Rebuilding"
+          $$1
+          if [ ! $$? -eq 0 ]; then
+            echo ""
+          fi
+        fi
+      done
+    done
+  else
+    echo "$$2 is not a valid directory"
+  fi
+}
+
+# Capture user input with defaults
+CMD=$${1:-make}
+DIR=$${2:-src}
+
+if [ $${CMD:0:2} = '-h' ]; then
+echo '
+This script will recompile a rust project using `make`
+every time something in the specified directory changes.
+
+Use: ./watch.sh [CMD] [DIR]
+Example: ./watch.sh "make run" src
+
+CMD: Command to execute
+     Complex commands may be passed as strings
+     `make` by default
+DIR: Directory to watch
+     src by default
+
+If DIR is supplied, CMD must be as well.\n'
+else
+  watch "$$CMD" "$$DIR"
+fi
+
+endef
+export WATCH_SCRIPT
+
+watch: $(TARGET_LIB_DIR)
+	$(Q)( \
+		test -e watch.sh \
+		&& echo "--- The file 'watch.sh' already exists" \
+	) \
+	|| \
+	( \
+		echo -e "$$WATCH_SCRIPT" > watch.sh \
+		&& chmod +x watch.sh \
+		&& echo "--- Created 'watch.sh'" \
+		&& echo "--- Type './watch.sh' to start compilation on save" \
+		&& echo "--- Type './watch.sh -h' for more options" \
+	)
+
+# borrowed from http://stackoverflow.com/q/649246/1256624
+define SYMLINK_BUILD_SCRIPT
+#!/bin/bash
+# written by bvssvni
+# Modify the setting to do conditional compilation.
+# For example "--cfg my_feature"
+SETTINGS=""
+# ================================================
+
+MAKE=make
+if [ "$$OS" == "Windows_NT" ]; then
+    MAKE=mingw32-make
+fi
+
+# Checks if an item exists in an array.
+# Copied from http://stackoverflow.com/questions/3685970/check-if-an-array-contains-a-value
+function contains() {
+    local n=$$#
+    local value=$${!n}
+    for ((i=1;i < $$#;i++)) {
+        if [ "$${!i}" == "$${value}" ]; then
+            echo "y"
+            return 0
+        fi
+    }
+    echo "n"
+    return 1
+}
+
+# This is a counter used to insert dependencies.
+# It is global because we need an array of all the
+# visited dependencies.
+i=0
+function build_deps {
+    local current=$$(pwd)
+    for symlib in $$(find $(TARGET_LIB_DIR) -type l) ; do
+        cd $$current
+        echo $$symlib
+        local original_file=$$(readlink $$symlib)
+        local original_dir=$$(dirname $$original_file)
+        cd $$original_dir
+
+        # Go to the git root directory.
+        local current_git_dir=$$(git rev-parse --show-toplevel)
+        echo "--- Parent $$current"
+        echo "--- Child $$current_git_dir"
+        cd $$current_git_dir
+
+        # Skip building if it is already built.
+        if [ $$(contains "$${git_dir[@]}" $$current_git_dir) == "y" ]; then
+            echo "--- Visited $$current_git_dir"
+            continue
+        fi
+
+        # Remember git directory to not build it twice
+        git_dir[i]=$$current_git_dir
+        let i+=1
+
+        # Visit the symlinks and build the dependencies
+        build_deps
+
+        # First check for a 'build.sh' script with default settings.
+        # Check for additional 'rust-empty.mk' file. \
+        # Compile with the settings flags. \
+        # If no other options, build with make.
+        ( \
+            test -e build.sh \
+            && ./build.sh \
+        ) \
+        || \
+        ( \
+            test -e rust-empty.mk \
+            && $$MAKE -f rust-empty.mk clean \
+            && $$MAKE -f rust-empty.mk \
+        ) \
+        || \
+        ( \
+            echo "--- Building $$current_git_dir" \
+            && $$MAKE clean \
+            && $$MAKE \
+        )
+    done
+    cd $$current
+}
+
+# Mark main project as visited to avoid infinite loop.
+git_dir[i]=$$(pwd)
+let i+=1
+if [ "$$1" == "deps" ]; then
+    build_deps
+fi
+
+echo "--- Building $$(pwd)"
+( \
+    test -e rust-empty.mk \
+    && $$MAKE -f rust-empty.mk clean \
+    && $$MAKE -f rust-empty.mk COMPILER_FLAGS+="$$SETTINGS" \
+) \
+|| \
+( \
+    $$MAKE clean
+    $$MAKE COMPILER_FLAGS+="$$SETTINGS"
+)
+
+endef
+export SYMLINK_BUILD_SCRIPT
+
+symlink-build:
+	$(Q)( \
+		test -e build.sh \
+		&& echo "--- The file 'build.sh' already exists" \
+	) \
+	|| \
+	( \
+		echo -e "$$SYMLINK_BUILD_SCRIPT" > build.sh \
+		&& chmod +x build.sh \
+		&& echo "--- Created 'build.sh'" \
+		&& echo "--- Type './build.sh deps' to build everything" \
+	)
+
 loc:
 	$(Q)echo "--- Counting lines of .rs files in 'src' (LOC):" \
 	&& find src/ -type f -name "*.rs" -exec cat {} \; | wc -l
@@ -438,7 +658,7 @@ loc:
 # prints the commit hash with remote branches containing that commit.
 symlink-info:
 	$(Q)	current=$$(pwd) ; \
-	for symlib in $$(find target/*/lib -type l) ; do \
+	for symlib in $$(find $(TARGET_LIB_DIR) -type l) ; do \
 		cd $$current ; \
 		echo $$symlib ; \
 		original_file=$$(readlink $$symlib) ; \
@@ -446,7 +666,11 @@ symlink-info:
 		cd $$original_dir ; \
 		commit=$$(git rev-parse HEAD) ; \
 		echo $$commit ; \
+		echo "origin:" ; \
 		git config --get remote.origin.url ; \
+		echo "upstream:" ; \
+		git config --get remote.upstream.url ; \
+		echo "available in remote branches:" ; \
 		git branch -r --contains $$commit ; \
 		echo "" ; \
 	done \
diff --git a/build.sh b/build.sh
new file mode 100755
index 0000000..da9b733
--- /dev/null
+++ b/build.sh
@@ -0,0 +1,78 @@
+#!/bin/bash
+# written by bvssvni
+# Modify the setting to do conditional compilation.
+# For example "--cfg my_feature"
+SETTINGS=""
+# ================================================
+
+MAKE=make
+if [ "$OS" == "Windows_NT" ]; then
+    MAKE=mingw32-make
+fi
+
+# Checks if an item exists in an array.
+# Copied from http://stackoverflow.com/questions/3685970/check-if-an-array-contains-a-value
+function contains() {
+    local n=$#
+    local value=${!n}
+    for ((i=1;i < $#;i++)) {
+        if [ "${!i}" == "${value}" ]; then
+            echo "y"
+            return 0
+        fi
+    }
+    echo "n"
+    return 1
+}
+
+# This is a counter used to insert dependencies.
+# It is global because we need an array of all the
+# visited dependencies.
+i=0
+function build_deps {
+    local current=$(pwd)
+    for symlib in $(find target/deps/ -type l) ; do
+        cd $current
+        echo $symlib
+        local original_file=$(readlink $symlib)
+        local original_dir=$(dirname $original_file)
+        cd $original_dir
+
+        # Go to the git root directory.
+        local current_git_dir=$(git rev-parse --show-toplevel)
+        echo "--- Parent $current"
+        echo "--- Child $current_git_dir"
+        cd $current_git_dir
+
+        # Skip building if it is already built.
+        if [ $(contains "${git_dir[@]}" $current_git_dir) == "y" ]; then
+            echo "--- Visited $current_git_dir"
+            continue
+        fi
+
+        # Remember git directory to not build it twice
+        git_dir[i]=$current_git_dir
+        let i+=1
+
+        # Visit the symlinks and build the dependencies
+        build_deps
+
+        # First check for a 'build.sh' script with default settings.
+        # Check for additional 'rust-empty.mk' file. # Compile with the settings flags. # If no other options, build with make.
+        ( test -e build.sh && ./build.sh ) || ( test -e rust-empty.mk && $MAKE -f rust-empty.mk clean && $MAKE -f rust-empty.mk ) || ( echo "--- Building $current_git_dir" && $MAKE clean && $MAKE )
+    done
+    cd $current
+}
+
+# Mark main project as visited to avoid infinite loop.
+git_dir[i]=$(pwd)
+let i+=1
+if [ "$1" == "deps" ]; then
+    build_deps
+fi
+
+echo "--- Building $(pwd)"
+( test -e rust-empty.mk && $MAKE -f rust-empty.mk clean && $MAKE -f rust-empty.mk COMPILER_FLAGS+="$SETTINGS" ) || ( $MAKE clean
+    $MAKE COMPILER_FLAGS+="$SETTINGS"
+)
+
diff --git a/src/app.rs b/src/app.rs
index e842913..f86559c 100644
--- a/src/app.rs
+++ b/src/app.rs
@@ -18,6 +18,7 @@ pub struct App<'a> {
     logo: Option<Texture>,
     comment1: Option<Texture>,
     comment2: Option<Texture>,
+    window_background_color: [f32, ..4],
 
     gl: Gl,
 }
@@ -32,6 +33,7 @@ impl<'a> App<'a> {
             logo: None,
             comment1: None,
             comment2: None,
+            window_background_color: [1.0, 1.0, 1.0, 1.0],
 
             gl: Gl::new(),
         }
@@ -90,17 +92,16 @@ impl<'a> Game for App<'a> {
         self.comment2 = Some(Texture::from_path(&asset_store.path("comment2.png").unwrap()).unwrap());
     }
 
-    fn render(&mut self, args: &mut RenderArgs) {
+    fn render(&mut self, args: &RenderArgs) {
+        self.gl.viewport(0, 0, args.width as i32, args.height as i32);
         let ref c = Context::abs(args.width as f64, args.height as f64);
-
-        let bg = c.rgba(self.settings.window_background_color[0], self.settings.window_background_color[1], self.settings.window_background_color[2], 1.0);
-        bg.draw(&mut self.gl);
+        c.color(self.window_background_color).draw(&mut self.gl);
 
         self.render_ui(c);
         self.board.render(self.number_renderer.get_ref(), c, &mut self.gl);
     }
 
-    fn update(&mut self, args: &mut UpdateArgs) {
+    fn update(&mut self, args: &UpdateArgs) {
         self.board.update(args.dt);
     }