diff --git a/package-lock.json b/package-lock.json
index de6dae4..06f82de 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,6 +1,6 @@
 {
   "name": "ethereum-htlc",
-  "version": "0.0.10",
+  "version": "0.0.11",
   "lockfileVersion": 1,
   "requires": true,
   "dependencies": {
@@ -2083,7 +2083,8 @@
         "console-control-strings": {
           "version": "1.1.0",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "core-util-is": {
           "version": "1.0.2",
@@ -2200,7 +2201,8 @@
         "inherits": {
           "version": "2.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "ini": {
           "version": "1.3.5",
@@ -2242,6 +2244,7 @@
           "version": "2.3.5",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "safe-buffer": "^5.1.2",
             "yallist": "^3.0.0"
@@ -2260,6 +2263,7 @@
           "version": "0.5.1",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "minimist": "0.0.8"
           }
@@ -2353,6 +2357,7 @@
           "version": "1.4.0",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "wrappy": "1"
           }
@@ -2438,7 +2443,8 @@
         "safe-buffer": {
           "version": "5.1.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "safer-buffer": {
           "version": "2.1.2",
@@ -2474,6 +2480,7 @@
           "version": "1.0.2",
           "bundled": true,
           "dev": true,
+          "optional": true,
           "requires": {
             "code-point-at": "^1.0.0",
             "is-fullwidth-code-point": "^1.0.0",
@@ -2537,12 +2544,14 @@
         "wrappy": {
           "version": "1.0.2",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         },
         "yallist": {
           "version": "3.0.3",
           "bundled": true,
-          "dev": true
+          "dev": true,
+          "optional": true
         }
       }
     },
@@ -4036,6 +4045,15 @@
         }
       }
     },
+    "map-age-cleaner": {
+      "version": "0.1.3",
+      "resolved": "https://registry.npmjs.org/map-age-cleaner/-/map-age-cleaner-0.1.3.tgz",
+      "integrity": "sha512-bJzx6nMoP6PDLPBFmg7+xRKeFZvFboMrGlxmNj9ClvX53KrmvM5bXFXEWjbz4cz1AFn+jWJ9z/DJSz7hrs0w3w==",
+      "dev": true,
+      "requires": {
+        "p-defer": "^1.0.0"
+      }
+    },
     "map-cache": {
       "version": "0.2.2",
       "resolved": "https://registry.npmjs.org/map-cache/-/map-cache-0.2.2.tgz",
@@ -4596,11 +4614,23 @@
       "resolved": "https://registry.npmjs.org/p-cancelable/-/p-cancelable-1.1.0.tgz",
       "integrity": "sha512-s73XxOZ4zpt1edZYZzvhqFa6uvQc1vwUa0K0BdtIZgQMAJj9IbebH+JkgKZc9h+B05PKHLOTl4ajG1BmNrVZlw=="
     },
+    "p-defer": {
+      "version": "1.0.0",
+      "resolved": "https://registry.npmjs.org/p-defer/-/p-defer-1.0.0.tgz",
+      "integrity": "sha1-n26xgvbJqozXQwBKfU+WsZaw+ww=",
+      "dev": true
+    },
     "p-finally": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/p-finally/-/p-finally-1.0.0.tgz",
       "integrity": "sha1-P7z7FbiZpEEjs0ttzBi3JDNqLK4="
     },
+    "p-is-promise": {
+      "version": "2.1.0",
+      "resolved": "https://registry.npmjs.org/p-is-promise/-/p-is-promise-2.1.0.tgz",
+      "integrity": "sha512-Y3W0wlRPK8ZMRbNq97l4M5otioeA5lm1z7bkNkxCka8HSPjR0xRWmpCmc9utiaLP9Jb1eD8BgeIxTW4AIF45Pg==",
+      "dev": true
+    },
     "p-limit": {
       "version": "1.3.0",
       "resolved": "https://registry.npmjs.org/p-limit/-/p-limit-1.3.0.tgz",
@@ -6708,7 +6738,7 @@
       "requires": {
         "underscore": "1.9.1",
         "web3-core-helpers": "1.2.1",
-        "websocket": "github:web3-js/WebSocket-Node#905deb4812572b344f5801f8c9ce8bb02799d82e"
+        "websocket": "github:web3-js/WebSocket-Node#polyfill/globalThis"
       },
       "dependencies": {
         "nan": {
@@ -6924,16 +6954,16 @@
       "dev": true
     },
     "yargs": {
-      "version": "11.1.0",
-      "resolved": "https://registry.npmjs.org/yargs/-/yargs-11.1.0.tgz",
-      "integrity": "sha512-NwW69J42EsCSanF8kyn5upxvjp5ds+t3+udGBeTbFnERA+lF541DDpMawzo4z6W/QrzNM18D+BPMiOBibnFV5A==",
+      "version": "11.1.1",
+      "resolved": "https://registry.npmjs.org/yargs/-/yargs-11.1.1.tgz",
+      "integrity": "sha512-PRU7gJrJaXv3q3yQZ/+/X6KBswZiaQ+zOmdprZcouPYtQgvNU35i+68M4b1ZHLZtYFT5QObFLV+ZkmJYcwKdiw==",
       "dev": true,
       "requires": {
         "cliui": "^4.0.0",
         "decamelize": "^1.1.1",
         "find-up": "^2.1.0",
         "get-caller-file": "^1.0.1",
-        "os-locale": "^2.0.0",
+        "os-locale": "^3.1.0",
         "require-directory": "^2.1.1",
         "require-main-filename": "^1.0.1",
         "set-blocking": "^2.0.0",
@@ -6941,6 +6971,75 @@
         "which-module": "^2.0.0",
         "y18n": "^3.2.1",
         "yargs-parser": "^9.0.2"
+      },
+      "dependencies": {
+        "execa": {
+          "version": "1.0.0",
+          "resolved": "https://registry.npmjs.org/execa/-/execa-1.0.0.tgz",
+          "integrity": "sha512-adbxcyWV46qiHyvSp50TKt05tB4tK3HcmF7/nxfAdhnox83seTDbwnaqKO4sXRy7roHAIFqJP/Rw/AuEbX61LA==",
+          "dev": true,
+          "requires": {
+            "cross-spawn": "^6.0.0",
+            "get-stream": "^4.0.0",
+            "is-stream": "^1.1.0",
+            "npm-run-path": "^2.0.0",
+            "p-finally": "^1.0.0",
+            "signal-exit": "^3.0.0",
+            "strip-eof": "^1.0.0"
+          }
+        },
+        "get-stream": {
+          "version": "4.1.0",
+          "resolved": "https://registry.npmjs.org/get-stream/-/get-stream-4.1.0.tgz",
+          "integrity": "sha512-GMat4EJ5161kIy2HevLlr4luNjBgvmj413KaQA7jt4V8B4RDsfpHk7WQ9GVqfYyyx8OS/L66Kox+rJRNklLK7w==",
+          "dev": true,
+          "requires": {
+            "pump": "^3.0.0"
+          }
+        },
+        "invert-kv": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/invert-kv/-/invert-kv-2.0.0.tgz",
+          "integrity": "sha512-wPVv/y/QQ/Uiirj/vh3oP+1Ww+AWehmi1g5fFWGPF6IpCBCDVrhgHRMvrLfdYcwDh3QJbGXDW4JAuzxElLSqKA==",
+          "dev": true
+        },
+        "lcid": {
+          "version": "2.0.0",
+          "resolved": "https://registry.npmjs.org/lcid/-/lcid-2.0.0.tgz",
+          "integrity": "sha512-avPEb8P8EGnwXKClwsNUgryVjllcRqtMYa49NTsbQagYuT1DcXnl1915oxWjoyGrXR6zH/Y0Zc96xWsPcoDKeA==",
+          "dev": true,
+          "requires": {
+            "invert-kv": "^2.0.0"
+          }
+        },
+        "mem": {
+          "version": "4.3.0",
+          "resolved": "https://registry.npmjs.org/mem/-/mem-4.3.0.tgz",
+          "integrity": "sha512-qX2bG48pTqYRVmDB37rn/6PT7LcR8T7oAX3bf99u1Tt1nzxYfxkgqDwUwolPlXweM0XzBOBFzSx4kfp7KP1s/w==",
+          "dev": true,
+          "requires": {
+            "map-age-cleaner": "^0.1.1",
+            "mimic-fn": "^2.0.0",
+            "p-is-promise": "^2.0.0"
+          }
+        },
+        "mimic-fn": {
+          "version": "2.1.0",
+          "resolved": "https://registry.npmjs.org/mimic-fn/-/mimic-fn-2.1.0.tgz",
+          "integrity": "sha512-OqbOk5oEQeAZ8WXWydlu9HJjz9WVdEIvamMCcXmuqUYjTknH/sqsWvhQ3vgwKFRR1HpjvNBKQ37nbJgYzGqGcg==",
+          "dev": true
+        },
+        "os-locale": {
+          "version": "3.1.0",
+          "resolved": "https://registry.npmjs.org/os-locale/-/os-locale-3.1.0.tgz",
+          "integrity": "sha512-Z8l3R4wYWM40/52Z+S265okfFj8Kt2cC2MKY+xNi3kFs+XGI7WXu/I309QQQYbRW4ijiZ+yxs9pqEhJh0DqW3Q==",
+          "dev": true,
+          "requires": {
+            "execa": "^1.0.0",
+            "lcid": "^2.0.0",
+            "mem": "^4.0.0"
+          }
+        }
       }
     },
     "yargs-parser": {