diff --git a/remix-tests/examples/simple_storage.sol b/remix-tests/examples/simple_storage.sol
index bc74b55c00..278155d1f1 100644
--- a/remix-tests/examples/simple_storage.sol
+++ b/remix-tests/examples/simple_storage.sol
@@ -13,5 +13,4 @@ contract SimpleStorage {
   function get() public view returns (uint retVal) {
     return storedData;
   }
-
 }
diff --git a/remix-tests/package.json b/remix-tests/package.json
index 24f876a21f..7285b8970f 100644
--- a/remix-tests/package.json
+++ b/remix-tests/package.json
@@ -38,6 +38,7 @@
   "homepage": "https://github.com/ethereum/remix-tests#readme",
   "dependencies": {
     "@types/async": "^2.4.0",
+    "@types/colors": "^1.2.1",
     "@types/web3": "^1.0.18",
     "async": "^2.6.0",
     "change-case": "^3.0.1",
@@ -54,6 +55,7 @@
     "yo-yoify": "latest"
   },
   "devDependencies": {
+    "@types/commander": "^2.12.2",
     "@types/mocha": "^5.2.5",
     "@types/node": "^10.12.21",
     "babel-preset-es2017": "^6.24.1",
diff --git a/remix-tests/src/run.ts b/remix-tests/src/run.ts
index 217a43e843..b4cd97fd15 100644
--- a/remix-tests/src/run.ts
+++ b/remix-tests/src/run.ts
@@ -1,17 +1,15 @@
-#!/usr/bin/env ts-node
-
-const commander = require('commander')
+import commander from 'commander'
 import Web3 from 'web3'
 import { runTestFiles } from './runTestFiles'
 import fs from './fileSystem'
 const Provider = require('remix-simulator').Provider
-import Log = require('./logger')
+import Log from './logger'
 const logger = new Log()
 const log = logger.logger
-require('colors')
+import colors from 'colors'
 
 // parse verbosity
-function mapVerbosity (v) {
+function mapVerbosity (v: number) {
     const levels = {
         0: 'error',
         1: 'warn',
@@ -39,7 +37,7 @@ commander
     .option('-v, --verbose <level>', 'run with verbosity', mapVerbosity)
     .action(function (filename) {
         // Console message
-        console.log(('\n\t👁 :: Running remix-tests - Unit testing for solidity :: 👁\t\n'),'color: white')
+        console.log(colors.white('\n\t👁\t:: Running remix-tests - Unit testing for solidity ::\t👁\n'))
         // set logger verbosity
         if (commander.verbose) {
             logger.setVerbosity(commander.verbose)
diff --git a/remix-tests/src/runTestFiles.ts b/remix-tests/src/runTestFiles.ts
index b6ea60ee3f..4b08d94595 100644
--- a/remix-tests/src/runTestFiles.ts
+++ b/remix-tests/src/runTestFiles.ts
@@ -1,13 +1,13 @@
-import async = require('async')
-import path = require('path')
+import async from 'async'
 import fs from './fileSystem'
-import { runTest } from './testRunner'
-require('colors')
+import { runTest, TestResultInterface, ResultsInterface } from './testRunner'
+import colors from 'colors'
+import Web3 from 'web3'
 
-import Compiler = require('./compiler')
-import Deployer = require('./deployer')
+import { compileFileOrFiles } from './compiler'
+import { deployAll } from './deployer'
 
-export function runTestFiles(filepath, isDirectory, web3, opts = {}) {
+export function runTestFiles(filepath: string, isDirectory: boolean, web3: Web3, opts?: object) {
     opts = opts || {}
     const { Signale } = require('signale')
     // signale configuration
@@ -33,38 +33,42 @@ export function runTestFiles(filepath, isDirectory, web3, opts = {}) {
     const signale = new Signale(options)
     let accounts = opts['accounts'] || null
     async.waterfall([
-        function getAccountList (next) {
+        function getAccountList (next: Function) {
             if (accounts) return next(null)
-            web3.eth.getAccounts((_err, _accounts) => {
+            web3.eth.getAccounts((_err: Error | null | undefined, _accounts) => {
                 accounts = _accounts
                 next(null)
             })
         },
-        function compile (next) {
-            Compiler.compileFileOrFiles(filepath, isDirectory, { accounts }, next)
+        function compile(next: Function) {
+            compileFileOrFiles(filepath, isDirectory, { accounts }, next)
         },
-        function deployAllContracts (compilationResult, next) {
-            Deployer.deployAll(compilationResult, web3, function (err, contracts) {
+        function deployAllContracts (compilationResult, next: Function) {
+            deployAll(compilationResult, web3, (err, contracts) => {
                 if (err) {
                     next(err)
                 }
                 next(null, compilationResult, contracts)
             })
         },
-        function determineTestContractsToRun (compilationResult, contracts, next) {
+        function determineTestContractsToRun (compilationResult, contracts, next: Function) {
             let contractsToTest: any[] = []
             let contractsToTestDetails: any[] = []
-            const gatherContractsFrom = (filename) => {
+            const gatherContractsFrom = function(filename: string) {
                 if (filename.indexOf('_test.sol') < 0) {
                     return
                 }
-                Object.keys(compilationResult[path.basename(filename)]).forEach(contractName => {
-                    contractsToTest.push(contractName)
-                    contractsToTestDetails.push(compilationResult[path.basename(filename)][contractName])
-                })
+                try {
+                  Object.keys(compilationResult[filename]).forEach(contractName => {
+                      contractsToTest.push(contractName)
+                      contractsToTestDetails.push(compilationResult[filename][contractName])
+                  })
+                } catch (e) {
+                  console.error(e)
+                }
             }
             if (isDirectory) {
-                fs.walkSync(filepath, foundpath => {
+                fs.walkSync(filepath, (foundpath: string) => {
                     gatherContractsFrom(foundpath)
                 })
             } else {
@@ -72,13 +76,14 @@ export function runTestFiles(filepath, isDirectory, web3, opts = {}) {
             }
             next(null, contractsToTest, contractsToTestDetails, contracts)
         },
-        function runTests (contractsToTest, contractsToTestDetails, contracts, next) {
-            let totalPassing = 0
-            let totalFailing = 0
-            let totalTime = 0
+        function runTests(contractsToTest, contractsToTestDetails, contracts, next: Function) {
+            let totalPassing: number = 0
+            let totalFailing: number = 0
+            let totalTime: number = 0
             let errors: any[] = []
 
-            var testCallback = function (result) {
+            var _testCallback = function (err: Error | null | undefined, result: TestResultInterface) {
+                if(err) throw err;
                 if (result.type === 'contract') {
                     signale.name(result.value.white)
                 } else if (result.type === 'testPass') {
@@ -88,20 +93,25 @@ export function runTestFiles(filepath, isDirectory, web3, opts = {}) {
                     errors.push(result)
                 }
             }
-            var resultsCallback = function (_err, result, cb) {
+            var _resultsCallback = (_err: Error | null | undefined, result: ResultsInterface, cb) => {
                 totalPassing += result.passingNum
                 totalFailing += result.failureNum
                 totalTime += result.timePassed
                 cb()
             }
 
-            async.eachOfLimit(contractsToTest, 1, (contractName, index, cb) => {
-                runTest(contractName, contracts(contractName), contractsToTestDetails[index], { accounts }, testCallback, (err, result) => {
+            async.eachOfLimit(contractsToTest, 1, (contractName: string, index, cb) => {
+              try {
+                runTest(contractName, contracts[contractName], contractsToTestDetails[index], { accounts }, _testCallback, (err, result) => {
                     if (err) {
+                      console.log(err)
                         return cb(err)
                     }
-                    resultsCallback(null, result, cb)
+                    _resultsCallback(null, result, cb)
                 })
+              } catch(e) {
+                console.error(e)
+              }
             }, function (err) {
                 if (err) {
                     return next(err)
@@ -109,23 +119,23 @@ export function runTestFiles(filepath, isDirectory, web3, opts = {}) {
 
                 console.log('\n')
                 if (totalPassing > 0) {
-                    console.log(('%c  ' + totalPassing + ' passing ') + ('%c(' + totalTime + 's)'),'color: green','color: grey')
+                    console.log(colors.green(totalPassing + ' passing ') + colors.grey('(' + totalTime + 's)'))
                 }
                 if (totalFailing > 0) {
-                    console.log(('%c  ' + totalFailing + ' failing'),'color: red')
+                    console.log(colors.red(totalFailing + ' failing'))
                 }
                 console.log('')
 
                 errors.forEach((error, index) => {
                     console.log('  ' + (index + 1) + ') ' + error.context + ' ' + error.value)
                     console.log('')
-                    console.log(('%c\t error: ' + error.errMsg),'color: red')
+                    console.log(colors.red('\t error: ' + error.errMsg))
                 })
                 console.log('')
 
                 next()
             })
         }
-    ], function () {
+    ], () => {
     })
 }
diff --git a/remix-tests/src/runTestSources.ts b/remix-tests/src/runTestSources.ts
index 34da06f5f6..ee989b11a5 100644
--- a/remix-tests/src/runTestSources.ts
+++ b/remix-tests/src/runTestSources.ts
@@ -37,7 +37,7 @@ export function runTestSources(contractSources, testCallback, resultCallback, fi
             compileContractSources(contractSources, importFileCb, opts, next)
         },
         function deployAllContracts (compilationResult, next) {
-            deployAll(compilationResult, web3, function (err, contracts) {
+            deployAll(compilationResult, web3, (err, contracts) => {
                 if (err) {
                     next(err)
                 }
@@ -58,10 +58,9 @@ export function runTestSources(contractSources, testCallback, resultCallback, fi
                     contractsToTest.push(contractName)
                 })
             }
-
             next(null, contractsToTest, contractsToTestDetails, contracts)
         },
-        function runTests (contractsToTest, contractsToTestDetails, contracts, next) {
+        function runTests(contractsToTest, contractsToTestDetails, contracts, next) {
             let totalPassing = 0
             let totalFailing = 0
             let totalTime = 0
diff --git a/remix-tests/src/testRunner.ts b/remix-tests/src/testRunner.ts
index b6d38470d2..72ed491331 100644
--- a/remix-tests/src/testRunner.ts
+++ b/remix-tests/src/testRunner.ts
@@ -2,7 +2,7 @@ import async from 'async'
 import * as changeCase from 'change-case'
 import Web3 from 'web3'
 
-interface CbReturnInterface {
+export interface TestResultInterface {
   type: string,
   value: any,
   time?: number,
@@ -10,13 +10,19 @@ interface CbReturnInterface {
   errMsg?: string
   filename?: string
 }
+interface RunListInterface {
+  name: string,
+  type: string,
+  constant: boolean,
+  signature?: any
+}
 export interface ResultsInterface {
     passingNum: number,
     failureNum: number,
     timePassed: number
 }
 export interface TestCbInterface {
-  (error: Error | null | undefined, result?: CbReturnInterface) : void;
+  (error: Error | null | undefined, result: TestResultInterface) : void;
 }
 export interface ResultCbInterface {
   (error: Error | null | undefined, result: ResultsInterface) : void;
@@ -47,27 +53,27 @@ function getTestFunctions (jsonInterface) {
     return jsonInterface.filter((x) => specialFunctions.indexOf(x.name) < 0 && x.type === 'function')
 }
 
-function createRunList (jsonInterface) {
+function createRunList(jsonInterface): RunListInterface[] {
     let availableFunctions = getAvailableFunctions(jsonInterface)
     let testFunctions = getTestFunctions(jsonInterface)
-    let runList: any[] = []
+    let runList: RunListInterface[] = []
 
     if (availableFunctions.indexOf('beforeAll') >= 0) {
-        runList.push({name: 'beforeAll', type: 'internal', constant: false})
+        runList.push({ name: 'beforeAll', type: 'internal', constant: false })
     }
 
     for (let func of testFunctions) {
         if (availableFunctions.indexOf('beforeEach') >= 0) {
-            runList.push({name: 'beforeEach', type: 'internal', constant: false})
+            runList.push({ name: 'beforeEach', type: 'internal', constant: false })
         }
-        runList.push({name: func.name, signature: func.signature, type: 'test', constant: func.constant})
+        runList.push({ name: func.name, signature: func.signature, type: 'test', constant: func.constant })
         if (availableFunctions.indexOf('afterEach') >= 0) {
-            runList.push({name: 'afterEach', type: 'internal', constant: false})
+            runList.push({ name: 'afterEach', type: 'internal', constant: false })
         }
     }
 
     if (availableFunctions.indexOf('afterAll') >= 0) {
-        runList.push({name: 'afterAll', type: 'internal', constant: false})
+        runList.push({ name: 'afterAll', type: 'internal', constant: false })
     }
 
     return runList
@@ -90,7 +96,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
         signale.warn('e.g: the following code won\'t work in the current context:')
         signale.warn('TestsAccounts.getAccount(' + opts.accounts.length + ')')
     }
-    const resp: CbReturnInterface = {
+    const resp: TestResultInterface = {
       type: 'contract',
       value: testName,
       filename: testObject.filename
@@ -113,7 +119,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
             method.call(sendParams).then((result) => {
                 let time = Math.ceil((Date.now() - startTime) / 1000.0)
                 if (result) {
-                    const resp: CbReturnInterface = {
+                    const resp: TestResultInterface = {
                       type: 'testPass',
                       value: changeCase.sentenceCase(func.name),
                       time: time,
@@ -123,7 +129,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
                     passingNum += 1
                     timePassed += time
                 } else {
-                    const resp: CbReturnInterface = {
+                    const resp: TestResultInterface = {
                       type: 'testFailure',
                       value: changeCase.sentenceCase(func.name),
                       time: time,
@@ -147,7 +153,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
                         if (event.raw.topics.indexOf(topic) >= 0) {
                             var testEvent = web3.eth.abi.decodeParameters(['bool', 'string'], event.raw.data)
                             if (!testEvent[0]) {
-                                const resp: CbReturnInterface = {
+                                const resp: TestResultInterface = {
                                   type: 'testFailure',
                                   value: changeCase.sentenceCase(func.name),
                                   time: time,
@@ -163,7 +169,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
                     }
 
                     if (testPassed) {
-                        const resp: CbReturnInterface = {
+                        const resp: TestResultInterface = {
                           type: 'testPass',
                           value: changeCase.sentenceCase(func.name),
                           time: time,
@@ -175,8 +181,7 @@ export function runTest(testName, testObject: any, contractDetails: any, opts: a
 
                     return next()
                 } catch (err) {
-                    console.log('error!')
-                    console.dir(err)
+                    console.error(err)
                     return next(err)
                 }
             }).on('error', function (err: Error | null | undefined) {