diff --git a/sys/Cargo.toml b/sys/Cargo.toml
index 7543358..fafbc09 100644
--- a/sys/Cargo.toml
+++ b/sys/Cargo.toml
@@ -1,6 +1,7 @@
 [package]
 name    = "ffmpeg-sys"
 version = "2.8.0-1"
+build   = "build.rs"
 
 authors = ["meh. <meh@schizofreni.co>"]
 license = "WTFPL"
@@ -13,9 +14,15 @@ keywords    = ["audio", "video"]
 libc = "*"
 
 [features]
-default  = ["avcodec", "avdevice", "avfilter", "avformat", "avresample", "postproc", "swresample", "swscale"]
+default  = ["avcodec", "avdevice", "avfilter", "avformat", "avresample", "swresample", "swscale"]
+
+static = []
+
+build          = ["static"]
+build-gpl      = []
+build-nonfree  = []
+build-version3 = []
 
-static     = []
 avcodec    = []
 avdevice   = ["avformat"]
 avfilter   = []
diff --git a/sys/build.rs b/sys/build.rs
new file mode 100644
index 0000000..ba2128e
--- /dev/null
+++ b/sys/build.rs
@@ -0,0 +1,244 @@
+use std::env;
+use std::fs;
+use std::io;
+use std::path::PathBuf;
+use std::process::Command;
+
+fn version() -> String {
+	let major: u8 = env::var("CARGO_PKG_VERSION_MAJOR").unwrap().parse().unwrap();
+	let minor: u8 = env::var("CARGO_PKG_VERSION_MINOR").unwrap().parse().unwrap();
+	let patch: u8 = env::var("CARGO_PKG_VERSION_PATCH").unwrap().parse().unwrap();
+
+	if patch == 0 {
+		format!("{}.{}", major, minor)
+	}
+	else {
+		format!("{}.{}.{}", major, minor, patch)
+	}
+}
+
+fn output() -> PathBuf {
+	PathBuf::from(env::var("OUT_DIR").unwrap())
+}
+
+fn source() -> PathBuf {
+	output().join(format!("ffmpeg-{}", version()))
+}
+
+fn search() -> PathBuf {
+	let mut absolute = env::current_dir().unwrap();
+	absolute.push(&output());
+	absolute.push("dist");
+
+	absolute
+}
+
+fn fetch() -> io::Result<()> {
+	let url    = format!("http://ffmpeg.org/releases/ffmpeg-{}.tar.bz2", version());
+	let status = try!(if cfg!(target_os = "linux") {
+		Command::new("wget")
+			.current_dir(&output())
+			.arg(url)
+			.arg("-c")
+			.arg("-O")
+			.arg("ffmpeg.tar.bz2")
+			.status()
+	}
+	else {
+		unimplemented!();
+	});
+
+	if status.success() {
+		Ok(())
+	}
+	else {
+		Err(io::Error::new(io::ErrorKind::Other, "fetch failed"))
+	}
+}
+
+fn extract() -> io::Result<()> {
+	let status = try!(if cfg!(target_os = "linux") {
+		Command::new("tar")
+			.current_dir(&output())
+			.arg("xf")
+			.arg("ffmpeg.tar.bz2")
+			.status()
+	}
+	else {
+		unimplemented!();
+	});
+
+	if status.success() {
+		Ok(())
+	}
+	else {
+		Err(io::Error::new(io::ErrorKind::Other, "extract failed"))
+	}
+}
+
+fn build() -> io::Result<()> {
+	let mut configure = Command::new("./configure");
+	configure.current_dir(&source());
+	configure.arg(format!("--prefix={}", search().to_string_lossy()));
+
+	if env::var("TARGET").unwrap() != env::var("HOST").unwrap() {
+		configure.arg(format!("--cross-prefix={}-", env::var("TARGET").unwrap()));
+	}
+
+	// control debug build
+	if env::var("DEBUG").is_ok() {
+		configure.arg("--enable-debug");
+		configure.arg("--disable-stripping");
+	}
+	else {
+		configure.arg("--disable-debug");
+		configure.arg("--enable-stripping");
+	}
+
+	// make it static
+	configure.arg("--enable-static");
+	configure.arg("--disable-shared");
+
+	// the binary using ffmpeg-sys must comply with GPL
+	if env::var("CARGO_FEATURE_BUILD_GPL").is_ok() {
+		configure.arg("--enable-gpl");
+	}
+	
+	// the binary using ffmpeg-sys must comply with (L)GPLv3
+	if env::var("CARGO_FEATURE_BUILD_VERSION3").is_ok() {
+		configure.arg("--enable-version3");
+	}
+
+	// the binary using ffmpeg-sys cannot be redistributed
+	if env::var("CARGO_FEATURE_BUILD_NONFREE").is_ok() {
+		configure.arg("--enable-nonfree");
+	}
+
+	// do not build programs since we don't need them
+	configure.arg("--disable-programs");
+
+	// disable/enable building libraries based on features
+	if env::var("CARGO_FEATURE_AVCODEC").is_ok() {
+		configure.arg("--enable-avcodec");
+	}
+	else {
+		configure.arg("--disable-avcodec");
+	}
+
+	if env::var("CARGO_FEATURE_AVDEVICE").is_ok() {
+		configure.arg("--enable-avdevice");
+	}
+	else {
+		configure.arg("--disable-avdevice");
+	}
+
+	if env::var("CARGO_FEATURE_AVFILTER").is_ok() {
+		configure.arg("--enable-avfilter");
+	}
+	else {
+		configure.arg("--disable-avfilter");
+	}
+
+	if env::var("CARGO_FEATURE_AVFORMAT").is_ok() {
+		configure.arg("--enable-avformat");
+	}
+	else {
+		configure.arg("--disable-avformat");
+	}
+
+	if env::var("CARGO_FEATURE_AVRESAMPLE").is_ok() {
+		configure.arg("--enable-avresample");
+	}
+	else {
+		configure.arg("--disable-avresample");
+	}
+
+	if env::var("CARGO_FEATURE_POSTPROC").is_ok() {
+		if env::var("CARGO_FEATURE_BUILD_GPL").is_err() {
+			return Err(io::Error::new(io::ErrorKind::Other, "postproc is GPL"));
+		}
+
+		configure.arg("--enable-postproc");
+	}
+	else {
+		configure.arg("--disable-postproc");
+	}
+
+	if env::var("CARGO_FEATURE_SWRESAMPLE").is_ok() {
+		configure.arg("--enable-swresample");
+	}
+	else {
+		configure.arg("--disable-swresample");
+	}
+
+	if env::var("CARGO_FEATURE_SWSCALE").is_ok() {
+		configure.arg("--enable-swscale");
+	}
+	else {
+		configure.arg("--disable-swscale");
+	}
+
+	// enable external codecs
+	configure.arg("--enable-avisynth");
+	configure.arg("--enable-avresample");
+	configure.arg("--enable-fontconfig");
+	configure.arg("--enable-gnutls");
+	configure.arg("--enable-ladspa");
+	configure.arg("--enable-libass");
+	configure.arg("--enable-libbluray");
+	configure.arg("--enable-libfreetype");
+	configure.arg("--enable-libfribidi");
+	configure.arg("--enable-libgsm");
+	configure.arg("--enable-libmodplug");
+	configure.arg("--enable-libmp3lame");
+	configure.arg("--enable-libopenjpeg");
+	configure.arg("--enable-libopus");
+	configure.arg("--enable-libpulse");
+	configure.arg("--enable-libschroedinger");
+	configure.arg("--enable-libsoxr");
+	configure.arg("--enable-libspeex");
+	configure.arg("--enable-libssh");
+	configure.arg("--enable-libtheora");
+	configure.arg("--enable-libv4l2");
+	configure.arg("--enable-libvorbis");
+	configure.arg("--enable-libvpx");
+	configure.arg("--enable-libwebp");
+
+	if env::var("CARGO_FEATURE_BUILD_GPL").is_ok() {
+		configure.arg("--enable-libx264");
+		configure.arg("--enable-libx265");
+		configure.arg("--enable-libxvid");
+	}
+
+	if env::var("CARGO_FEATURE_BUILD_VERSION3").is_ok() {
+		configure.arg("--enable-libopencore_amrnb");
+		configure.arg("--enable-libopencore_amrwb");
+	}
+
+	if !try!(configure.status()).success() {
+		return Err(io::Error::new(io::ErrorKind::Other, "configure failed"));
+	}
+
+	if !try!(Command::new("make").current_dir(&source()).status()).success() {
+		return Err(io::Error::new(io::ErrorKind::Other, "make failed"));
+	}
+
+	if !try!(Command::new("make").current_dir(&source()).arg("install").status()).success() {
+		return Err(io::Error::new(io::ErrorKind::Other, "install failed"));
+	}
+
+	Ok(())
+}
+
+fn main() {
+	println!("cargo:rustc-link-search=native={}", search().join("lib").to_string_lossy());
+
+	if fs::metadata(&search().join("lib").join("libavutil.a")).is_ok() {
+		return;
+	}
+
+	fs::create_dir_all(&output()).ok().expect("failed to create build directory");
+	fetch().unwrap();
+	extract().unwrap();
+	build().unwrap();
+}