diff --git a/Cargo.toml b/Cargo.toml
index 326de10..3736f15 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -1,7 +1,12 @@
 [package]
 name = "merkletree-rs"
 version = "0.0.1"
-authors = ["arnaucube <arnaucube@gmail.com>"]
+authors = ["arnaucube <root@arnaucube.com>"]
+edition = "2018"
+license = "GPL-3.0"
+description = "Sparse MerkleTree"
+repository = "https://github.com/arnaucube/merkletree-rs"
+readme = "README.md"
 
 [dependencies]
 tiny-keccak = "1.4.2"
diff --git a/README.md b/README.md
index 8dbfce4..a403d4b 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,4 @@
-# merkletree-rs [![Build Status](https://travis-ci.org/arnaucube/merkletree-rs.svg?branch=master)](https://travis-ci.org/arnaucube/merkletree-rs)
+# merkletree-rs [![Crates.io](https://img.shields.io/crates/v/merkletree-rs.svg)](https://crates.io/crates/merkletree-rs) [![Build Status](https://travis-ci.org/arnaucube/merkletree-rs.svg?branch=master)](https://travis-ci.org/arnaucube/merkletree-rs)
 Sparse MerkleTree implementation in Rust.
 
 The MerkleTree is optimized in the design and concepts, to have a faster and lighter MerkleTree, maintaining compatibility with a non optimized MerkleTree. In this way, the MerkleRoot of the optimized MerkleTree will be the same that the MerkleRoot of the non optimized MerkleTree.
diff --git a/src/db.rs b/src/db.rs
index 4ac917a..fa5c4c5 100644
--- a/src/db.rs
+++ b/src/db.rs
@@ -2,7 +2,7 @@ extern crate rusty_leveldb;
 
 use self::rusty_leveldb::DB;
 
-use constants;
+use super::constants;
 
 pub struct Db {
     storage: DB,
diff --git a/src/lib.rs b/src/lib.rs
index aa28009..cee5f5c 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -6,10 +6,10 @@ extern crate tiny_keccak;
 
 use rustc_hex::ToHex;
 
-mod constants;
-mod db;
-mod node;
-mod utils;
+pub mod constants;
+pub mod db;
+pub mod node;
+pub mod utils;
 
 type Result<T> = std::result::Result<T, String>;
 
diff --git a/src/node.rs b/src/node.rs
index 337c772..d556878 100644
--- a/src/node.rs
+++ b/src/node.rs
@@ -1,5 +1,5 @@
-use constants;
-use utils;
+use super::constants;
+use super::utils;
 
 pub struct TreeNode {
     pub child_l: [u8; 32],
diff --git a/src/utils.rs b/src/utils.rs
index b544ad1..ef1693b 100644
--- a/src/utils.rs
+++ b/src/utils.rs
@@ -1,5 +1,5 @@
-use constants;
-use node;
+use super::constants;
+use super::node;
 use tiny_keccak::Keccak;
 
 pub fn hash_vec(b: Vec<u8>) -> [u8; 32] {