diff --git a/lib/createdb.js b/lib/createdb.js
index bda00cd..0695e99 100755
--- a/lib/createdb.js
+++ b/lib/createdb.js
@@ -1,7 +1,6 @@
 #!/usr/bin/env node
 const args = require("commander");
 const packageInfo = require("../package");
-const { startsWith } = require("./mapper");
 var postgresClient = require("pg-native");
 var sqlite3 = require("sqlite3");
 
@@ -55,7 +54,7 @@ const createDbPostgres = function (sessions) {
 const main = function (argv_) {
   const argv = argv_ || process.argv;
   args.parse(argv);
-  if (startsWith(args.sessions, "postgresql://")) {
+  if (args.sessions.startsWith("postgresql://")) {
     createDbPostgres(args.sessions);
   } else {
     createDbSqlite(args.sessions);
diff --git a/lib/mapper.js b/lib/mapper.js
index 9dd3dcd..ae26584 100644
--- a/lib/mapper.js
+++ b/lib/mapper.js
@@ -3,19 +3,6 @@ var sqlite3 = require("sqlite3");
 var postgresClient = require("pg-native");
 var watchFile = require("node-watch");
 
-var startsWith = function (subjectString, searchString) {
-  var reversedSubjectString = subjectString.split('').reverse().join('');
-  var reversedSearchString = searchString.split('').reverse().join('');
-  return endsWith(reversedSubjectString, reversedSearchString);
-}
-
-var endsWith = function (subjectString, searchString) {
-  var position = subjectString.length;
-  position -= searchString.length;
-  var lastIndex = subjectString.indexOf(searchString, position);
-  return lastIndex !== -1 && lastIndex === position;
-};
-
 var updateFromJson = function (path, map) {
   var content = fs.readFileSync(path, "utf8");
   var keyToSession = JSON.parse(content);
@@ -155,12 +142,12 @@ var mapFor = function (path, pollingInterval) {
   var map = {};
   var loadMap;
   var watch;
-  if (endsWith(path, ".sqlite")) {
+  if (path.endsWith(".sqlite")) {
     loadMap = function () {
       updateFromSqlite(path, map);
     };
     watch = watchFile;
-  } else if (startsWith(path, "postgresql://")) {
+  } else if (path.startsWith("postgresql://")) {
     loadMap = function () {
       updateFromPostgres(path, map);
     };
@@ -179,6 +166,4 @@ var mapFor = function (path, pollingInterval) {
   return map;
 };
 
-exports.endsWith = endsWith;
 exports.mapFor = mapFor;
-exports.startsWith = startsWith;