diff --git a/src/main.rs b/src/bin/main.rs
similarity index 93%
rename from src/main.rs
rename to src/bin/main.rs
index b4ec3ec..41dcbe4 100644
--- a/src/main.rs
+++ b/src/bin/main.rs
@@ -1,3 +1,6 @@
+extern crate httpserve;
+use httpserve::ThreadPool;
+
 use std::io::prelude::*;
 use std::fs;
 use std::net::TcpStream;
@@ -10,13 +13,13 @@ fn main() {
     let listener = TcpListener::bind("127.0.0.1:7878").unwrap();
     let counter = Arc::new(Mutex::new(0usize));
 
-    //let pool = ThreadPool::new(100);
+    let tasks = ThreadPool::new(100);
 
     for stream in listener.incoming() {
         let stream = stream.unwrap();
         let counter = Arc::clone(&counter);
 
-        thread::spawn(move || {
+        tasks.queue(move || {
             {
                 // in a subscope to release borrow automatically
                 let mut count = counter.lock().unwrap();
diff --git a/src/lib.rs b/src/lib.rs
new file mode 100644
index 0000000..c16aabc
--- /dev/null
+++ b/src/lib.rs
@@ -0,0 +1,69 @@
+use std::sync::{Arc, Mutex};
+use std::sync::mpsc;
+use std::thread;
+
+trait FnBox {
+  fn call_box(self: Box<Self>);
+}
+
+impl<F: FnOnce()> FnBox for F {
+    fn call_box(self: Box<F>) {
+        (*self)();
+    }
+}
+
+type Job = Box<dyn FnOnce() + Send + 'static>;
+
+struct Worker {
+    id: usize,
+    thread: thread::JoinHandle<()>,
+}
+
+impl Worker {
+    pub fn new(id: usize, receiver: Arc<Mutex<mpsc::Receiver<Job>>>) -> Worker {
+        Worker {
+            id,
+            thread: thread::spawn(move || {
+                loop {
+                    let job = receiver.lock().expect("unrecoverable poisened panicked thread state").recv().unwrap();
+
+                    println!("such busy, so worker #{}!", id);
+
+                    job.call_box();
+                }
+            }),
+        }
+    }
+}
+
+pub struct ThreadPool {
+    workers: Vec<Worker>,
+    sender: mpsc::Sender<Job>,
+}
+
+impl ThreadPool {
+    pub fn new(size: usize) -> ThreadPool {
+        assert!(size > 0);
+
+        let (sender, receiver) = mpsc::channel();
+        let receiver = Arc::new(Mutex::new(receiver));
+
+        let mut workers = Vec::with_capacity(size);
+
+        for id in 0..size {
+            workers.push(Worker::new(id, Arc::clone(&receiver)))
+        }
+
+        //ThreadPool.max = size;
+        ThreadPool {
+            workers,
+            sender,
+        }
+    }
+
+    pub fn run<F: FnOnce() + Send + 'static>(&self, task: F)
+    {
+        let task = Box::new(task);
+        self.sender.send(task).unwrap();
+    }
+}