diff --git a/batch_resolve.toml b/batch_resolve.toml
index d09453c..0fa62b7 100644
--- a/batch_resolve.toml
+++ b/batch_resolve.toml
@@ -9,3 +9,6 @@ dns = [
 
 # Times to retry on connection timeout
 retry = 5
+
+# Number of async tasks in execution buffer
+parallel_tasks = 1000
\ No newline at end of file
diff --git a/src/config.rs b/src/config.rs
index a2dac3f..a7f3206 100644
--- a/src/config.rs
+++ b/src/config.rs
@@ -19,15 +19,6 @@ lazy_static! {
     pub static ref CONFIG: StaticWrapper<Config> = StaticWrapper(Config::new());
 }
 
-macro_rules! uncell {
-    ($expr:expr) => (*$expr.borrow())
-}
-
-macro_rules! uncell_mut {
-    ($expr:expr) => (*$expr.borrow_mut())
-}
-
-
 #[derive(Clone, Debug)]
 pub struct Config {
     dns_servers: RefCell<Rc<Vec<SocketAddr>>>,
@@ -79,6 +70,10 @@ impl Config {
         if let Some(retry) = cfg_fmt.retry {
             uncell_mut!(self.timeout_retries) = retry;
         }
+
+        if let Some(par_tasks) = cfg_fmt.parallel_tasks {
+            uncell_mut!(self.task_buffer_size) = par_tasks;
+        }
     
         Ok(())
     }
@@ -88,6 +83,7 @@ impl Config {
 struct ConfigFormat {
     dns: Option<Vec<String>>,
     retry: Option<u32>,
+    parallel_tasks: Option<usize>,
 }
 
 #[derive(Debug)]
diff --git a/src/main.rs b/src/main.rs
index f14c908..2578f5c 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -1,8 +1,7 @@
 #[macro_use] extern crate lazy_static;
 #[macro_use] extern crate serde_derive;
-#[macro_use] extern crate derive_new;
 extern crate serde;
-extern crate serde_yaml;
+extern crate toml;
 
 #[macro_use] extern crate log;
 #[macro_use] extern crate clap;