diff --git a/client/dom/events/index.js b/client/dom/events/index.js
index 195987da..85c24a3d 100644
--- a/client/dom/events/index.js
+++ b/client/dom/events/index.js
@@ -32,7 +32,7 @@ function EventsProto() {
         
         switch(type) {
         default:
-            if (!/element$/.test(type))
+            if (!type.endsWith('element'))
                 throw Error('unknown eventName: ' + type);
             
             parseArgs(
diff --git a/client/dom/files.js b/client/dom/files.js
index dce0ac39..6d9627d4 100644
--- a/client/dom/files.js
+++ b/client/dom/files.js
@@ -36,8 +36,8 @@ function check(name) {
 }
 
 function getModule(name) {
-    const regExpHTML = new RegExp(FILES_HTML + '|' + FILES_HTML_ROOT);
-    const regExpJSON = new RegExp(FILES_JSON);
+    const regExpHTML = RegExp(FILES_HTML + '|' + FILES_HTML_ROOT);
+    const regExpJSON = RegExp(FILES_JSON);
     
     const isHTML = regExpHTML.test(name);
     const isJSON = regExpJSON.test(name);
@@ -54,7 +54,7 @@ function getModule(name) {
 
 function getPath(name, isHTML, isJSON) {
     let path;
-    const regExp = new RegExp(FILES_HTML_ROOT);
+    const regExp = RegExp(FILES_HTML_ROOT);
     const isRoot = regExp.test(name);
     
     if (isHTML) {
diff --git a/client/modules/user-menu/parse-user-menu.js b/client/modules/user-menu/parse-user-menu.js
index 78ce016f..d4013405 100644
--- a/client/modules/user-menu/parse-user-menu.js
+++ b/client/modules/user-menu/parse-user-menu.js
@@ -14,7 +14,7 @@ module.exports = (userMenu) => {
             continue;
         }
         
-        if (/^_/.test(str)) {
+        if (str.startsWith('_')) {
             continue;
         }
         
diff --git a/client/sw/sw.js b/client/sw/sw.js
index 3c849bd8..ff9a23fe 100644
--- a/client/sw/sw.js
+++ b/client/sw/sw.js
@@ -15,7 +15,7 @@ const respondWith = currify((f, e) => {
     const {url} = request;
     const pathname = getPathName(url);
     
-    if (/\/$/.test(url) || /\^\/fs/.test(pathname))
+    if (url.endsWith('/') || /\^\/fs/.test(pathname))
         return;
     
     if (!isGet(request))
@@ -24,7 +24,7 @@ const respondWith = currify((f, e) => {
     if (!isBasic(request))
         return;
     
-    if (/^\/api/.test(pathname))
+    if (pathname.startsWith('/api'))
         return;
     
     if (/^socket.io/.test(pathname))
diff --git a/server/markdown/index.spec.js b/server/markdown/index.spec.js
index d6e9c338..bc736bef 100644
--- a/server/markdown/index.spec.js
+++ b/server/markdown/index.spec.js
@@ -27,14 +27,14 @@ const {request} = require('serve-once')(cloudcmd, {
 test('cloudcmd: markdown: error', async (t) => {
     const {body} = await request.get('/api/v1/markdown/not-found');
     
-    t.ok(/ENOENT/.test(body), 'should not found');
+    t.match(body, 'ENOENT', 'should not found');
     t.end();
 });
 
 test('cloudcmd: markdown: relative: error', async (t) => {
     const {body} = await request.get('/api/v1/markdown/not-found?relative');
     
-    t.ok(/ENOENT/.test(body), 'should not found');
+    t.match(body, 'ENOENT', 'should not found');
     t.end();
 });
 
diff --git a/server/rest/index.js b/server/rest/index.js
index cbd65d44..b3989191 100644
--- a/server/rest/index.js
+++ b/server/rest/index.js
@@ -87,7 +87,7 @@ function rest(config, request, response) {
  */
 function sendData(params, config, callback) {
     const p = params;
-    const isMD = /^\/markdown/.test(p.name);
+    const isMD = p.name.startsWith('/markdown');
     const rootDir = config('root');
     
     if (isMD)
@@ -122,7 +122,7 @@ function onGET(params, config, callback) {
     if (p.name[0] === '/')
         cmd = p.name.replace('/', '');
     
-    if (/^pack/.test(cmd)) {
+    if (cmd.startsWith('pack')) {
         cmd = cmd.replace(/^pack/, '');
         streamPack(root(cmd, rootDir), p.response, packer);
         return;
diff --git a/test/rest/pack.js b/test/rest/pack.js
index aff32c61..8ad25b7a 100644
--- a/test/rest/pack.js
+++ b/test/rest/pack.js
@@ -137,7 +137,7 @@ test('cloudcmd: rest: pack: tar: put: error', async (t) => {
         ]),
     });
     
-    t.ok(/^ENOENT: no such file or directory/.test(body), 'should return error');
+    t.match(body, /^ENOENT: no such file or directory/, 'should return error');
     t.end();
 });
 
@@ -219,7 +219,7 @@ test('cloudcmd: rest: pack: zip: put: error', async (t) => {
         ]),
     });
     
-    t.ok(/^ENOENT: no such file or directory/.test(body), 'should return error');
+    t.match(body, /^ENOENT: no such file or directory/, 'should return error');
     t.end();
 });