diff --git a/Cargo.toml b/Cargo.toml
index c9dc02143..75e7899b2 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -17,30 +17,30 @@ keywords = ["search", "information", "retrieval"]
 [dependencies]
 byteorder = "0.4"
 memmap = "0.2"
-lazy_static = "0.1.15"
+lazy_static = "0.1"
 regex = "0.1"
-fst = "0.1.34"
+fst = "0.1"
 atomicwrites = "0.0.14"
-tempfile = "2.0.0"
-rustc-serialize = "0.3.16"
-log = "0.3.5"
-combine = "1.3.0"
-tempdir = "0.3.4"
-bincode = "0.4.0"
+tempfile = "2.0"
+rustc-serialize = "0.3"
+log = "0.3"
+combine = "1.3"
+tempdir = "0.3"
+bincode = "0.4"
 libc = "0.2.6"
 num_cpus = "0.2"
-itertools = "0.4.16"
-lz4 = "1.13.131"
-time = "0.1.34"
+itertools = "0.4"
+lz4 = "1.13"
+time = "0.1"
 uuid = "0.1"
-chan = "0.1.18"
-crossbeam = "0.2.10"
+chan = "0.1"
+crossbeam = "0.2"
 
 [dev-dependencies]
-rand = "0.3.13"
+rand = "0.3"
 
 [build-dependencies]
-gcc = "0.3.24"
+gcc = "0.3"
 
 # [profile.release]
 # debug = true
diff --git a/src/datastruct/stacker/heap.rs b/src/datastruct/stacker/heap.rs
index ac5ee5bd8..18142e584 100644
--- a/src/datastruct/stacker/heap.rs
+++ b/src/datastruct/stacker/heap.rs
@@ -123,7 +123,7 @@ impl InnerHeap {
         }
         else {
             if self.next_heap.is_none() {
-                println!("exceed heap size");
+                warn!("Exceeded heap size. The margin was apparently unsufficient. The segment will be committed right after indexing this very last document.");
                 self.next_heap = Some(Box::new(InnerHeap::with_capacity(self.buffer_len as usize)));
             }
             self.next_heap.as_mut().unwrap().allocate(num_bytes) + self.buffer_len
diff --git a/src/indexer/index_writer.rs b/src/indexer/index_writer.rs
index 1cce1c5b1..e15f63bbb 100644
--- a/src/indexer/index_writer.rs
+++ b/src/indexer/index_writer.rs
@@ -51,8 +51,7 @@ fn index_documents(heap: &mut Heap,
 	for doc in document_iterator {
 		try!(segment_writer.add_document(&doc, &schema));
 		if segment_writer.is_buffer_full() {
-			println!("no more space committing.");
-			println!("seg max doc {}", segment_writer.max_doc());
+			info!("Buffer limit reached, flushing segment with maxdoc={}.", segment_writer.max_doc());
 			break;
 		}
 	}
diff --git a/src/lib.rs b/src/lib.rs
index 2c0105a93..257897112 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -15,6 +15,9 @@ Tantivy is a search engine library.
 #[macro_use]
 extern crate lazy_static;
 
+#[macro_use]
+extern crate log;
+
 #[macro_use]
 extern crate fst;
 extern crate byteorder;
@@ -35,6 +38,8 @@ extern crate itertools;
 extern crate chan;
 extern crate crossbeam;
 
+
+
 #[cfg(test)] extern crate test;
 #[cfg(test)] extern crate rand;