diff --git a/README.md b/README.md
index 2dae8e8..027540c 100644
--- a/README.md
+++ b/README.md
@@ -1,2 +1,36 @@
-# circom_tester
+# circom tester
+## Setup
+1. Create new node js project.
+2. Install `circom_tester` and `chai` packges.
+3. Install `mocha` packge to run the tests.
 
+
+## Creating & Running a test file
+
+Create a js file contain the following code or use the src provided in the following section.
+<br>Execue `mocha -p -r ts-node/register 'multiplier2.js'` to run the test file.
+
+multiplier2.js ([src](test/multiplier2.js))
+``` multiplier2.js
+const chai = require("chai");
+const path = require("path");
+const wasm_tester = require("./../index").wasm;
+const c_tester = require("./../index").c;
+
+const F1Field = require("ffjavascript").F1Field;
+const Scalar = require("ffjavascript").Scalar;
+exports.p = Scalar.fromString("21888242871839275222246405745257275088548364400416034343698204186575808495617");
+const Fr = new F1Field(exports.p);
+
+const assert = chai.assert;
+
+describe("Simple test", function () {
+    this.timeout(100000);
+
+    it("Checking the compilation of a simple circuit generating wasm", async function () {
+        const circuit = await wasm_tester(path.join(__dirname, "Multiplier2circom"));
+        const w = await circuit.calculateWitness({a: 2, b: 4});
+        await circuit.checkConstraints(w);
+    });
+});
+```
diff --git a/c/tester.js b/c/tester.js
index 26922ad..c93f854 100644
--- a/c/tester.js
+++ b/c/tester.js
@@ -78,13 +78,13 @@ async function compile (baseName, fileName, options) {
     if (options.verbose) flags += "--verbose ";
 
     try {
-	b = await exec("circom " + flags + fileName);
-	if (options.verbose) {
+	      let b = await exec("circom " + flags + fileName);
+	      if (options.verbose) {
             console.log(b.stdout);
-	}
+	      }
     } catch (e) {
-	assert(false,
-	       "circom compiler error \n" + e);
+	      assert(false,
+	             "circom compiler error \n" + e);
     }
 
     const c_folder = path.join(options.output, baseName+"_cpp/")
@@ -245,7 +245,7 @@ function check_versions ( v1, v2 ) {
 async function compiler_above_version(v) {
     let output = (await exec('circom --version')).stdout;
     let compiler_version = version_to_list(output.slice(output.search(/\d/),-1));
-    vlist = version_to_list(v);
+    let vlist = version_to_list(v);
     return check_versions ( compiler_version, vlist );
 }
 
diff --git a/wasm/tester.js b/wasm/tester.js
index 42fbcf5..71e14b2 100644
--- a/wasm/tester.js
+++ b/wasm/tester.js
@@ -83,16 +83,16 @@ async function compile (fileName, options) {
     if (options.verbose) flags += "--verbose ";
 
     try {
-	b = await exec("circom " + flags + fileName);
-	if (options.verbose) {
+	      let b = await exec("circom " + flags + fileName);
+	      if (options.verbose) {
             console.log(b.stdout);
-	}
-	if (b.stderr != '') {
-		throw(b.stderr);
+	      }
+	      if (b.stderr != '') {
+		        throw(b.stderr);
         }
     } catch (e) {
-	assert(false,
-	       "circom compiler error \n" + e);
+	      assert(false,
+	             "circom compiler error \n" + e);
     }
 }
 
@@ -236,6 +236,6 @@ function check_versions ( v1, v2 ) {
 async function compiler_above_version(v) {
     let output = (await exec('circom --version')).stdout;
     let compiler_version = version_to_list(output.slice(output.search(/\d/),-1));
-    vlist = version_to_list(v);
+    let vlist = version_to_list(v);
     return check_versions ( compiler_version, vlist );
 }