diff --git a/backend/cmd/threads/main.ha b/backend/cmd/threads/main.ha
index 9c259c4..e73b8aa 100644
--- a/backend/cmd/threads/main.ha
+++ b/backend/cmd/threads/main.ha
@@ -1,45 +1,16 @@
 use types::c;
 use fmt;
+use thread;
 
-export type pthread_t = u64;
-export type pthread_attr_t = opaque;
-export type pthread_fn = fn(nullable *opaque) nullable *opaque;
-
-export @symbol("pthread_create") fn pthread_create(thread: nullable *pthread_t, attr: nullable *pthread_attr_t, start_routine: *pthread_fn, arg: nullable *opaque) int;
-export @symbol("pthread_join") fn pthread_join(thread: pthread_t, nullable *nullable *opaque) int;
-
-fn thread_start(arg: nullable *opaque) nullable *opaque = {
+fn thread_start() void = {
 	fmt::println("hello from another thread")!;
-	return null;
 };
 
 export fn main() void = {
 	fmt::println("starting a thread")!;
-	let tid: pthread_t = 0;
-	let ret = pthread_create(&tid, null, &thread_start, null);
-	fmt::printfln("ret: {}", ret)!;
+	let tid = thread::spawn(&thread_start)!;
 
 	fmt::println("joining")!;
-	ret = pthread_join(tid, null);
-	fmt::printfln("ret: {}", ret)!;
-};
-
-
-// spawn a thread
-//
-// returns a handle or an error
-fn spawn(f: *pthread_fn) (join_handle | error) = {
-	void;
-};
-
-// join a thread
-//
-// no return value or an error on join
-fn join(handle: join_handle) (void | error) = {
-	void;
-};
-
-// detach a thread.
-fn detach(join_handle) (void | error) = {
-	void;
+	thread::join(tid)!;
+	fmt::println("joined. good bye.")!;
 };
diff --git a/backend/vendor/hare-thread/thread/thread.ha b/backend/vendor/hare-thread/thread/thread.ha
new file mode 100644
index 0000000..b0b51ad
--- /dev/null
+++ b/backend/vendor/hare-thread/thread/thread.ha
@@ -0,0 +1,56 @@
+use types::c;
+
+export type pthread_t = [8]u8;
+type pthread_attr_t = opaque;
+type pthread_fn = fn(nullable *opaque) nullable *opaque;
+export type thread_fn = fn() void;
+
+@symbol("pthread_create") fn pthread_create(thread: nullable *pthread_t, attr: nullable *pthread_attr_t, start_routine: *pthread_fn, arg: nullable *opaque) int;
+@symbol("pthread_join") fn pthread_join(thread: pthread_t, nullable *nullable *opaque) int;
+@symbol("pthread_detach") fn pthread_detach(thread: pthread_t) int;
+
+fn thread_spawn_wrapper(data: nullable *opaque) nullable *opaque = {
+	let f = data: *thread_fn;
+	f();
+	return null;
+};
+
+export type error = !void;
+export type join_handle = struct {
+	thread: pthread_t,
+};
+
+// spawn a thread
+//
+// returns a handle or an error
+export fn spawn(f: *thread_fn) (join_handle | error) = {
+	let data = f: *opaque;
+
+	let tid: pthread_t = [0...];
+	let ret = pthread_create(&tid, null, &thread_spawn_wrapper, f);
+	if (ret != 0) {
+		return error;
+	};
+
+	return join_handle {
+		thread = tid
+	};
+};
+
+// join a thread
+//
+// no return value or an error on join
+export fn join(handle: join_handle) (void | error) = {
+	let ret = pthread_join(handle.thread, null);
+	if (ret != 0) {
+		return error;
+	};
+};
+
+// detach a thread.
+export fn detach(handle: join_handle) (void | error) = {
+	let ret = pthread_detach(handle.thread);
+	if (ret != 0) {
+		return error;
+	};
+};