diff --git a/.travis.yml b/.travis.yml
index 9a68c0c..65b8b0a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -1,5 +1,8 @@
 language: node_js
 node_js:
+  - "6"
   - "8"
+install:
+  - "npm install -g typescript"
+  - "npm install"
 script: "npm run-script tests"
-sudo: false
\ No newline at end of file
diff --git a/README.md b/README.md
index 904f26c..4517aca 100644
--- a/README.md
+++ b/README.md
@@ -15,90 +15,92 @@ $ npm install node-persistent-software
 
 ### Attributes
 
-* ``` string software ``` path to the software
-* ``` array arguments ``` arguments passed to the software
-* ``` object options ``` options passed to the software
-* ``` object currentChildProcess ``` current child_process
-* ``` boolean ended ``` if ended, don't restart it
-* ``` int maxCountRun ``` max start iteration
-* ``` int successCountRun ``` current success start iteration
-* ``` asynchronous-eventemitter eventEmitter ``` async events manager
+* ``` maxCountRun: number ``` max start iteration
+* ``` successCountRun: number ``` current success start iteration
 
 ### Constructor
 
-* ``` constructor(string software [, array arguments [, object options ] ] ) ``` => see [spawn documentation](https://nodejs.org/api/child_process.html#child_process_child_process_spawn_command_args_options)
+* ``` constructor(software: string, args?: Array<string>, options?: object) ``` => see [spawn documentation](https://nodejs.org/api/child_process.html#child_process_child_process_spawn_command_args_options)
 
 ### Methods
 
-* ``` max(int maxIteration) : this ``` change max iterations and reset current
+* ``` max(maxIteration: number) : this ``` change max iterations and reset current
 * ``` infinite() : this ``` no max iteration and reset current
 * ``` start() : this ``` run the software for the first time
-* ``` end() : this ``` stop the software and don't restart it
+* ``` end() : this ``` stop the software and does not restart it
 
 ### Events
 
-* ``` on("error", (string err) => {}) : this ``` fire if an error occurs (use try/catch to avoid loop)
+* ``` on("error", (err: Error) => void) : this ``` fire if an error occurs (use try/catch to avoid loop)
 
-* ``` on("firststart", () => {}) : this ``` fire if the software starts for the first time
-* ``` on("restart", () => {}) : this ``` fire if the software restarts
-* ``` on("start", (object child_process) => {}) : this ``` fire if the software starts (firststart && restart) => see [spawn documentation](https://nodejs.org/api/child_process.html#child_process_child_process_spawn_command_args_options)
+* ``` on("firststart", () => void) : this ``` fire if the software starts for the first time
+* ``` on("restart", () => void) : this ``` fire if the software restarts
+* ``` on("start", (child_process: child_process.ChildProcess) => void) : this ``` fire if the software starts (firststart && restart) => see [spawn documentation](https://nodejs.org/api/child_process.html#child_process_child_process_spawn_command_args_options)
 
-* ``` on("stop", () => {}) : this ``` fire if the software is killed
-* ``` on("end", () => {}) : this ``` fire if the software is killed and cannot be restarted
+* ``` on("stop", () => void) : this ``` fire if the software is killed
+* ``` on("end", () => void) : this ``` fire if the software is killed and cannot be restarted
 
 ## Examples
 
-```js
-const PersistantSoftware = require('node-persistent-software');
+### Native
 
-new PersistantSoftware(
-  "C:\\Program Files\\Mozilla Firefox\\firefox.exe",
-  [ "https://www.npmjs.com/package/node-persistent-software" ]
-).on("error", (msg) => {
+```javascript
+const PersistantSoftware = require("node-persistent-software");
+
+new PersistantSoftware("node", [ "-v" ]).on("error", (msg) => {
   console.log(msg);
 })
 
 .infinite()
 
 .on("firststart", () => {
-  console.log("Firefox is started for the first time !");
+  console.log("node is started for the first time !");
 }).on("restart", () => {
-  console.log("Firefox is started again...");
+  console.log("node is started again...");
 }).on("start", (child_process) => {
-  console.log("anyway, Firefox is started.");
+  console.log("anyway, node is started.");
 })
 
 .on("stop", () => {
-  console.log("Firefox is stopped, trying to restart...");
+  console.log("node is stopped, trying to restart...");
 }).on("end", () => {
-  console.log("/!\\ Firefox is stopped and cannot be restarted /!\\");
+  console.log("/!\\ node is stopped and cannot be restarted /!\\");
 }).start();
 
 
-new PersistantSoftware(
-  "C:\\Program Files\\Mozilla Firefox\\firefox.exe",
-  [ "https://github.com/Psychopoulet/node-persistent-software" ]
-).on("error", (msg) {
-  console.log(msg);
+new PersistantSoftware("node", [ "-v" ]).on("error", (err) => {
+  console.log(err);
 })
 
 .max(5)
 
 .on("firststart", () => {
-  console.log("Firefox is started for the first time !");
+  console.log("node is started for the first time !");
 }).on("restart", () => {
-  console.log("Firefox is started again...");
+  console.log("node is started again...");
 }).on("start", () => {
-  console.log("anyway, Firefox is started.");
+  console.log("anyway, node is started.");
 })
 
 .on("stop", () => {
-  console.log("Firefox is stopped, trying to restart...");
+  console.log("node is stopped, trying to restart...");
 }).on("end", () => {
-  console.log("/!\\ Firefox is stopped and cannot be restarted /!\\");
+  console.log("/!\\ node is stopped and cannot be restarted /!\\");
 }).start();
 ```
 
+### Typescript
+
+```typescript
+import PersistantSoftware = require("node-persistent-software");
+
+new PersistantSoftware("node", [ "-v" ]).on("error", (err) => {
+  console.log(err);
+})
+
+.infinite();
+```
+
 ## Tests
 
 ```bash
diff --git a/lib/index.d.ts b/lib/index.d.ts
new file mode 100644
index 0000000..4e1affa
--- /dev/null
+++ b/lib/index.d.ts
@@ -0,0 +1,26 @@
+/// <reference types="node" />
+
+declare module "node-persistent-software" {
+
+	class PersistantSoftware extends require("asynchronous-eventemitter") {
+
+		protected _software: string;
+		protected _args: Array<string>;
+		protected _options: object;
+		protected _ended: boolean;
+
+		public maxCountRun: number;
+		public successCountRun: number;
+
+		constructor(software: string, args?: Array<string>, options?: object);
+
+		public max(max: number): PersistantSoftware;
+		public infinite(): PersistantSoftware;
+		public start(): PersistantSoftware;
+		public end(): PersistantSoftware;
+
+	}
+
+	export = PersistantSoftware;
+
+}
diff --git a/lib/main.js b/lib/main.js
index 6afd741..302e9ee 100644
--- a/lib/main.js
+++ b/lib/main.js
@@ -9,17 +9,17 @@
 
 module.exports = class PersistantSoftware extends require("asynchronous-eventemitter") {
 
-	constructor (software, args, options) {
+	constructor (software, args = null, options = null) {
 
 		super();
 
-		this.software = software;
-		this.args = args && "object" === typeof args && args instanceof Array ? args : null;
-		this.options = options && "object" === typeof options ? options : null;
+		this._software = software;
+		this._args = args && "object" === typeof args && args instanceof Array ? args : null;
+		this._options = options && "object" === typeof options ? options : null;
 
-		this.currentChildProcess = null;
+		this._currentChildProcess = null;
 
-		this.ended = false;
+		this._ended = false;
 
 		this.infinite();
 
@@ -42,23 +42,23 @@ module.exports = class PersistantSoftware extends require("asynchronous-eventemi
 
 		try {
 
-			if (!this.ended) {
+			if (!this._ended) {
 
-				if (!this.args) {
-					this.currentChildProcess = spawn(this.software);
+				if (!this._args) {
+					this._currentChildProcess = spawn(this._software);
 				}
-				else if (!this.options) {
-					this.currentChildProcess = spawn(this.software, this.args);
+				else if (!this._options) {
+					this._currentChildProcess = spawn(this._software, this._args);
 				}
 				else {
-					this.currentChildProcess = spawn(this.software, this.args, this.options);
+					this._currentChildProcess = spawn(this._software, this._args, this._options);
 				}
 
-				this.currentChildProcess.on("error", (err) => {
+				this._currentChildProcess.on("error", (err) => {
 					this.emit("error", err);
 				});
 
-				if (!this.currentChildProcess || !this.currentChildProcess.pid) {
+				if (!this._currentChildProcess || !this._currentChildProcess.pid) {
 					this.end();
 				}
 				else {
@@ -72,13 +72,13 @@ module.exports = class PersistantSoftware extends require("asynchronous-eventemi
 						this.emit("firststart");
 					}
 
-					this.emit("start", this.currentChildProcess);
+					this.emit("start", this._currentChildProcess);
 
-					this.currentChildProcess.on("exit", () => {
+					this._currentChildProcess.on("exit", () => {
 
 						this.emit("stop");
 
-						if (!this.ended) {
+						if (!this._ended) {
 
 							if (0 >= this.maxCountRun) {
 								this.start();
@@ -109,14 +109,14 @@ module.exports = class PersistantSoftware extends require("asynchronous-eventemi
 
 	end () {
 
-		this.ended = true;
+		this._ended = true;
 
-		if (this.currentChildProcess) {
+		if (this._currentChildProcess) {
 
-			if (this.currentChildProcess.pid) {
+			if (this._currentChildProcess.pid) {
 
 				try {
-					process.kill(this.currentChildProcess.pid);
+					process.kill(this._currentChildProcess.pid);
 				}
 				catch (e) {
 					// nothing to do here
@@ -124,18 +124,11 @@ module.exports = class PersistantSoftware extends require("asynchronous-eventemi
 
 			}
 
-			this.currentChildProcess = null;
+			this._currentChildProcess = null;
 
 		}
 
-		this.emit("end")
-			.removeAllListeners("start")
-			.removeAllListeners("firststart")
-			.removeAllListeners("restart")
-			.removeAllListeners("stop")
-			.removeAllListeners("end");
-
-		return this;
+		return this.emit("end");
 
 	}
 
diff --git a/package.json b/package.json
index 53c4102..dfbedfe 100644
--- a/package.json
+++ b/package.json
@@ -1,14 +1,14 @@
 {
   "name": "node-persistent-software",
-  "version": "1.3.0",
+  "version": "1.4.0",
   "description": "Spawn a software and keep it running",
   "main": "lib/main.js",
+  "typings": "lib/index.d.ts",
   "scripts": {
-    "start": "node lib/main.js",
     "tests": "gulp tests"
   },
-  "pre-commit": [
-    "test"
+  "pre-push": [
+    "tests"
   ],
   "repository": {
     "type": "git",
@@ -28,16 +28,17 @@
     "url": "https://github.com/Psychopoulet/node-persistent-software/issues"
   },
   "dependencies": {
-    "asynchronous-eventemitter": "0.3.0"
+    "asynchronous-eventemitter": "0.3.2"
   },
   "devDependencies": {
+    "@types/node": "9.6.6",
     "gulp": "3.9.1",
     "gulp-plumber": "1.1.0",
     "gulp-eslint": "4.0.0",
     "gulp-mocha": "3.0.1",
     "gulp-istanbul": "1.1.2",
     "gulp-coveralls": "0.1.4",
-    "pre-commit": "1.2.2"
+    "pre-push": "0.1.1"
   },
   "homepage": "https://github.com/Psychopoulet/node-persistent-software#readme",
   "engines": {
diff --git a/tests/0_compilation_typescript.js b/tests/0_compilation_typescript.js
new file mode 100644
index 0000000..82b619d
--- /dev/null
+++ b/tests/0_compilation_typescript.js
@@ -0,0 +1,37 @@
+
+"use strict";
+
+// deps
+
+	const { exec } = require("child_process");
+	const { join } = require("path");
+	const { unlink } = require("fs");
+
+// consts
+
+	const MAX_TIMEOUT = 10000;
+
+// tests
+
+describe("compilation typescript", () => {
+
+	after((done) => {
+
+		unlink(join(__dirname, "typescript", "compilation.js"), (err) => {
+			return err ? done(err) : done();
+		});
+
+	});
+
+	it("should compile typescript file", (done) => {
+
+		exec("tsc " + join(__dirname, "typescript", "compilation.ts"), {
+			"cwd": join(__dirname, ".."),
+			"windowsHide": true
+		}, (err) => {
+			return err ? done(err) : done();
+		});
+
+	}).timeout(MAX_TIMEOUT);
+
+});
diff --git a/tests/tests.js b/tests/tests.js
index 65e479b..fca9bcc 100644
--- a/tests/tests.js
+++ b/tests/tests.js
@@ -9,6 +9,7 @@
 // consts
 
 	const IPCONFIG = "win32" === require("os").platform() ? "ipconfig" : "ifconfig";
+	const MAX_TIMEOUT = 10000;
 
 // tests
 
@@ -36,7 +37,7 @@ describe("run", () => {
 
 		});
 
-	}).timeout(1 * 1000);
+	}).timeout(MAX_TIMEOUT);
 
 	it("should check no args running", () => {
 
@@ -63,7 +64,7 @@ describe("run", () => {
 
 		});
 
-	}).timeout(1 * 1000);
+	}).timeout(MAX_TIMEOUT);
 
 	it("should check normal running with max", () => {
 
@@ -90,7 +91,7 @@ describe("run", () => {
 
 		});
 
-	}).timeout(1 * 1000);
+	}).timeout(MAX_TIMEOUT);
 
 	it("should check normal running with infinite and end", () => {
 
@@ -113,7 +114,7 @@ describe("run", () => {
 
 		});
 
-	}).timeout(1 * 1000);
+	}).timeout(MAX_TIMEOUT);
 
 	it("should check normal running with infinite and end", () => {
 
@@ -151,6 +152,6 @@ describe("run", () => {
 
 		});
 
-	}).timeout(5 * 1000);
+	}).timeout(MAX_TIMEOUT);
 
 });
diff --git a/tests/typescript/compilation.ts b/tests/typescript/compilation.ts
new file mode 100644
index 0000000..f7cd573
--- /dev/null
+++ b/tests/typescript/compilation.ts
@@ -0,0 +1,44 @@
+/// <reference path="../../lib/index.d.ts" />
+
+import PersistantSoftware = require("../../lib/main.js");
+
+new PersistantSoftware("node", [ "-v" ]).on("error", (err: Error) => {
+  console.log(err);
+})
+
+.infinite()
+
+.on("firststart", () => {
+  console.log("node is started for the first time !");
+}).on("restart", () => {
+  console.log("node is started again...");
+}).on("start", (child_process) => {
+  console.log("anyway, node is started.");
+})
+
+.on("stop", () => {
+  console.log("node is stopped, trying to restart...");
+}).on("end", () => {
+  console.log("/!\\ node is stopped and cannot be restarted /!\\");
+}).start();
+
+
+new PersistantSoftware("node", [ "-v" ]).on("error", (err: Error) => {
+  console.log(err);
+})
+
+.max(5)
+
+.on("firststart", () => {
+  console.log("node is started for the first time !");
+}).on("restart", () => {
+  console.log("node is started again...");
+}).on("start", () => {
+  console.log("anyway, node is started.");
+})
+
+.on("stop", () => {
+  console.log("node is stopped, trying to restart...");
+}).on("end", () => {
+  console.log("/!\\ node is stopped and cannot be restarted /!\\");
+}).start();