diff --git a/package-lock.json b/package-lock.json
index 013d300f..e6c2b38a 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -4758,7 +4758,7 @@
         },
         "onetime": {
           "version": "1.1.0",
-          "resolved": "https://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
+          "resolved": "http://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
           "integrity": "sha1-ofeDj4MUxRbwXs78vEzP4EtO14k=",
           "dev": true
         },
@@ -4900,7 +4900,7 @@
         },
         "onetime": {
           "version": "1.1.0",
-          "resolved": "https://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
+          "resolved": "http://registry.npmjs.org/onetime/-/onetime-1.1.0.tgz",
           "integrity": "sha1-ofeDj4MUxRbwXs78vEzP4EtO14k=",
           "dev": true
         },
@@ -7390,9 +7390,9 @@
       }
     },
     "typescript": {
-      "version": "3.5.3",
-      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.5.3.tgz",
-      "integrity": "sha512-ACzBtm/PhXBDId6a6sDJfroT2pOWt/oOnk4/dElG5G33ZL776N3Y6/6bKZJBFpd+b05F3Ct9qDjMeJmRWtE2/g==",
+      "version": "3.7.5",
+      "resolved": "https://registry.npmjs.org/typescript/-/typescript-3.7.5.tgz",
+      "integrity": "sha512-/P5lkRXkWHNAbcJIiHPfRoKqyd7bsyCma1hZNUGfn20qm64T6ZBlrzprymeu918H+mB/0rIg2gGK/BXkhhYgBw==",
       "dev": true
     },
     "uglify-es": {
@@ -7407,7 +7407,7 @@
       "dependencies": {
         "commander": {
           "version": "2.14.1",
-          "resolved": "https://registry.npmjs.org/commander/-/commander-2.14.1.tgz",
+          "resolved": "http://registry.npmjs.org/commander/-/commander-2.14.1.tgz",
           "integrity": "sha512-+YR16o3rK53SmWHU3rEM3tPAh2rwb1yPcQX5irVn7mb0gXbwuCCrnkbV5+PBfETdfg1vui07nM6PCG1zndcjQw==",
           "dev": true
         },
diff --git a/package.json b/package.json
index 981ba646..fee1d6c9 100644
--- a/package.json
+++ b/package.json
@@ -41,7 +41,7 @@
         "rollup-plugin-typescript2": "^0.23.0",
         "tslib": "^1.10.0",
         "tslint": "^5.19.0",
-        "typescript": "^3.5.3",
+        "typescript": "^3.7.5",
         "uglify-es": "^3.3.10",
         "ws": "^6.2.1"
     },
diff --git a/test/test.js b/test/test.js
index b1ac5f2f..32439e23 100644
--- a/test/test.js
+++ b/test/test.js
@@ -560,7 +560,7 @@ test.cb('connect, send, receive, reconnect', t => {
 });
 
 test.cb('immediately-failed connection should not timeout', t => {
-    const ws = new ReconnectingWebSocket('ws://thiswillfail.com', null, {
+    const ws = new ReconnectingWebSocket('ws://255.255.255.255', null, {
         maxRetries: 2,
         connectionTimeout: 500,
     });
@@ -570,7 +570,7 @@ test.cb('immediately-failed connection should not timeout', t => {
             t.fail();
         }
         if (ws.retryCount === 2) {
-            setTimeout(() => t.end(), 1500);
+            setTimeout(() => t.end(), 500);
         }
         if (ws.retryCount > 2) {
             t.fail();
@@ -579,9 +579,9 @@ test.cb('immediately-failed connection should not timeout', t => {
 });
 
 test.cb('immediately-failed connection with 0 maxRetries must not retry', t => {
-    const ws = new ReconnectingWebSocket('ws://thiswillfail.com', [], {
+    const ws = new ReconnectingWebSocket('ws://255.255.255.255', [], {
         maxRetries: 0,
-        connectionTimeout: 500,
+        connectionTimeout: 2000,
         minReconnectionDelay: 100,
         maxReconnectionDelay: 200,
     });
@@ -597,7 +597,7 @@ test.cb('immediately-failed connection with 0 maxRetries must not retry', t => {
         }
         setTimeout(() => {
             t.end();
-        }, 500);
+        }, 2100);
     });
 });
 
@@ -771,7 +771,7 @@ test.cb('closing from the other side should allow to keep closed', t => {
 });
 
 test.cb('reconnection delay grow factor', t => {
-    const ws = new ReconnectingWebSocket('wss://bad.url', [], {
+    const ws = new ReconnectingWebSocket('wss://255.255.255.255', [], {
         minReconnectionDelay: 100,
         maxReconnectionDelay: 1000,
         reconnectionDelayGrowFactor: 2,