diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index a1d614e..8321aed 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -26,6 +26,7 @@ mirror:
 snyk:
   stage: security
   script:
+    - npmci npm prepare
     - npmci command npm install -g snyk
     - npmci command npm install --ignore-scripts
     - npmci command snyk test
@@ -36,21 +37,11 @@ snyk:
 # ====================
 # test stage
 # ====================
-testLEGACY:
-  stage: test
-  script:
-  - npmci node install legacy
-  - npmci npm install
-  - npmci npm test
-  coverage: /\d+.?\d+?\%\s*coverage/
-  tags:
-  - docker
-  - notpriv
-  allow_failure: true
 
 testLTS:
   stage: test
   script:
+  - npmci npm prepare
   - npmci node install lts
   - npmci npm install
   - npmci npm test
@@ -62,6 +53,7 @@ testLTS:
 testSTABLE:
   stage: test
   script:
+  - npmci npm prepare
   - npmci node install stable
   - npmci npm install
   - npmci npm test
@@ -118,6 +110,7 @@ pages:
   stage: metadata
   script:
     - npmci command npm install -g typedoc typescript
+    - npmci npm prepare
     - npmci npm install
     - npmci command typedoc --module "commonjs" --target "ES2016" --out public/ ts/
   tags:
@@ -130,13 +123,3 @@ pages:
     paths:
     - public
   allow_failure: true
-
-windowsCompatibility:
-  image: stefanscherer/node-windows:10-build-tools
-  stage: metadata
-  script:
-  - npm install & npm test
-  coverage: /\d+.?\d+?\%\s*coverage/
-  tags:
-  - windows
-  allow_failure: true
diff --git a/package-lock.json b/package-lock.json
index 6b0aae0..b8bac37 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -236,6 +236,18 @@
       "integrity": "sha1-kQ3lDvzHwJ49gvL4er1rcAwYgYo=",
       "dev": true
     },
+    "ansi-regex": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/ansi-regex/-/ansi-regex-2.1.1.tgz",
+      "integrity": "sha1-w7M6te42DYbg5ijwRorn7yfWVN8=",
+      "dev": true
+    },
+    "ansi-styles": {
+      "version": "2.2.1",
+      "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-2.2.1.tgz",
+      "integrity": "sha1-tDLdM1i2NM914eRmQ2gkBTPB3b4=",
+      "dev": true
+    },
     "argparse": {
       "version": "1.0.10",
       "resolved": "https://registry.npmjs.org/argparse/-/argparse-1.0.10.tgz",
@@ -263,6 +275,32 @@
       "integrity": "sha1-x57Zf380y48robyXkLzDZkdLS3k=",
       "dev": true
     },
+    "babel-code-frame": {
+      "version": "6.26.0",
+      "resolved": "https://registry.npmjs.org/babel-code-frame/-/babel-code-frame-6.26.0.tgz",
+      "integrity": "sha1-Y/1D99weO7fONZR9uP42mj9Yx0s=",
+      "dev": true,
+      "requires": {
+        "chalk": "^1.1.3",
+        "esutils": "^2.0.2",
+        "js-tokens": "^3.0.2"
+      },
+      "dependencies": {
+        "chalk": {
+          "version": "1.1.3",
+          "resolved": "http://registry.npmjs.org/chalk/-/chalk-1.1.3.tgz",
+          "integrity": "sha1-qBFcVeSnAv5NFQq9OHKCKn4J/Jg=",
+          "dev": true,
+          "requires": {
+            "ansi-styles": "^2.2.1",
+            "escape-string-regexp": "^1.0.2",
+            "has-ansi": "^2.0.0",
+            "strip-ansi": "^3.0.0",
+            "supports-color": "^2.0.0"
+          }
+        }
+      }
+    },
     "balanced-match": {
       "version": "1.0.0",
       "resolved": "https://registry.npmjs.org/balanced-match/-/balanced-match-1.0.0.tgz",
@@ -291,6 +329,12 @@
       "integrity": "sha512-MQcXEUbCKtEo7bhqEs6560Hyd4XaovZlO/k9V3hjVUF/zwW7KBVdSK4gIt/bzwS9MbR5qob+F5jusZsb0YQK2A==",
       "dev": true
     },
+    "builtin-modules": {
+      "version": "1.1.1",
+      "resolved": "https://registry.npmjs.org/builtin-modules/-/builtin-modules-1.1.1.tgz",
+      "integrity": "sha1-Jw8HbFpywC9bZaR9+Uxf46J4iS8=",
+      "dev": true
+    },
     "chai": {
       "version": "4.1.2",
       "resolved": "https://registry.npmjs.org/chai/-/chai-4.1.2.tgz",
@@ -320,6 +364,37 @@
       "integrity": "sha512-sydDC3S3pNAQMYwJrs6dQX0oBQ6KfIPuOZ78n7rocW0eJJlsHPh2t3kwW7xfwYA/1Bf6/arGtSUo16rxR2JFlw==",
       "dev": true
     },
+    "chalk": {
+      "version": "2.4.1",
+      "resolved": "https://registry.npmjs.org/chalk/-/chalk-2.4.1.tgz",
+      "integrity": "sha512-ObN6h1v2fTJSmUXoS3nMQ92LbDK9be4TV+6G+omQlGJFdcUX5heKi1LZ1YnRMIgwTLEj3E24bT6tYni50rlCfQ==",
+      "dev": true,
+      "requires": {
+        "ansi-styles": "^3.2.1",
+        "escape-string-regexp": "^1.0.5",
+        "supports-color": "^5.3.0"
+      },
+      "dependencies": {
+        "ansi-styles": {
+          "version": "3.2.1",
+          "resolved": "https://registry.npmjs.org/ansi-styles/-/ansi-styles-3.2.1.tgz",
+          "integrity": "sha512-VT0ZI6kZRdTh8YyJw3SMbYm/u+NqfsAxEpWO0Pf9sq8/e94WxxOpPKx9FR1FlyCtOVDNOQ+8ntlqFxiRc+r5qA==",
+          "dev": true,
+          "requires": {
+            "color-convert": "^1.9.0"
+          }
+        },
+        "supports-color": {
+          "version": "5.5.0",
+          "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-5.5.0.tgz",
+          "integrity": "sha512-QjVjwdXIt408MIiAqCX4oUKsgU2EqAGzs2Ppkm4aQYbjm+ZEWEcW4SfFNTr4uMNZma0ey4f5lgLrkB0aX0QMow==",
+          "dev": true,
+          "requires": {
+            "has-flag": "^3.0.0"
+          }
+        }
+      }
+    },
     "check-error": {
       "version": "1.0.2",
       "resolved": "https://registry.npmjs.org/check-error/-/check-error-1.0.2.tgz",
@@ -355,6 +430,21 @@
         "readable-stream": "^2.3.5"
       }
     },
+    "color-convert": {
+      "version": "1.9.3",
+      "resolved": "https://registry.npmjs.org/color-convert/-/color-convert-1.9.3.tgz",
+      "integrity": "sha512-QfAUtd+vFdAtFQcC8CCyYt1fYWxSqAiK2cSD6zDB8N3cpsEBAvRxp9zOGg6G/SHHJYAT88/az/IuDGALsNVbGg==",
+      "dev": true,
+      "requires": {
+        "color-name": "1.1.3"
+      }
+    },
+    "color-name": {
+      "version": "1.1.3",
+      "resolved": "https://registry.npmjs.org/color-name/-/color-name-1.1.3.tgz",
+      "integrity": "sha1-p9BVi9icQveV3UIyj3QIMcpTvCU=",
+      "dev": true
+    },
     "combined-stream": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/combined-stream/-/combined-stream-1.0.6.tgz",
@@ -364,6 +454,12 @@
         "delayed-stream": "~1.0.0"
       }
     },
+    "commander": {
+      "version": "2.19.0",
+      "resolved": "https://registry.npmjs.org/commander/-/commander-2.19.0.tgz",
+      "integrity": "sha512-6tvAOO+D6OENvRAh524Dh9jcfKTYDQAqvqezbCW82xj5X0pSrcpxtvRKHLG0yBY6SD7PSDrJaj+0AiOcKVd1Xg==",
+      "dev": true
+    },
     "concat-map": {
       "version": "0.0.1",
       "resolved": "https://registry.npmjs.org/concat-map/-/concat-map-0.0.1.tgz",
@@ -415,6 +511,12 @@
       "integrity": "sha512-eGuFFw7Upda+g4p+QHvnW0RyTX/SVeJBDM/gCtMARO0cLuT2HcEKnTPvhjV6aGeqrCB/sbNop0Kszm0jsaWU4A==",
       "dev": true
     },
+    "esutils": {
+      "version": "2.0.2",
+      "resolved": "https://registry.npmjs.org/esutils/-/esutils-2.0.2.tgz",
+      "integrity": "sha1-Cr9PHKpbyx96nYrMbepPqqBLrJs=",
+      "dev": true
+    },
     "figures": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/figures/-/figures-2.0.0.tgz",
@@ -487,6 +589,21 @@
       "integrity": "sha1-Dovf5NHduIVNZOBOp8AOKgJuVlg=",
       "dev": true
     },
+    "has-ansi": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/has-ansi/-/has-ansi-2.0.0.tgz",
+      "integrity": "sha1-NPUEnOHs3ysGSa8+8k5F7TVBbZE=",
+      "dev": true,
+      "requires": {
+        "ansi-regex": "^2.0.0"
+      }
+    },
+    "has-flag": {
+      "version": "3.0.0",
+      "resolved": "https://registry.npmjs.org/has-flag/-/has-flag-3.0.0.tgz",
+      "integrity": "sha1-tdRU3CGZriJWmfNGfloH87lVuv0=",
+      "dev": true
+    },
     "inflight": {
       "version": "1.0.6",
       "resolved": "https://registry.npmjs.org/inflight/-/inflight-1.0.6.tgz",
@@ -521,6 +638,12 @@
       "integrity": "sha1-6PvzdNxVb/iUehDcsFctYz8s+hA=",
       "dev": true
     },
+    "js-tokens": {
+      "version": "3.0.2",
+      "resolved": "https://registry.npmjs.org/js-tokens/-/js-tokens-3.0.2.tgz",
+      "integrity": "sha1-mGbfOVECEw449/mWvOtlRDIJwls=",
+      "dev": true
+    },
     "js-yaml": {
       "version": "3.12.0",
       "resolved": "https://registry.npmjs.org/js-yaml/-/js-yaml-3.12.0.tgz",
@@ -633,6 +756,12 @@
       "integrity": "sha1-F0uSaHNVNP+8es5r9TpanhtcX18=",
       "dev": true
     },
+    "path-parse": {
+      "version": "1.0.6",
+      "resolved": "https://registry.npmjs.org/path-parse/-/path-parse-1.0.6.tgz",
+      "integrity": "sha512-GSmOT2EbHrINBf9SR7CDELwlJ8AENk3Qn7OikK4nFYAu3Ote2+JYNVvkpAEQm3/TLNEJFD/xZJjzyxg3KBWOzw==",
+      "dev": true
+    },
     "pathval": {
       "version": "1.1.0",
       "resolved": "https://registry.npmjs.org/pathval/-/pathval-1.1.0.tgz",
@@ -684,12 +813,27 @@
       "integrity": "sha1-3mMSg3P8v3w8z6TeWkgMRaZ5WOs=",
       "dev": true
     },
+    "resolve": {
+      "version": "1.8.1",
+      "resolved": "https://registry.npmjs.org/resolve/-/resolve-1.8.1.tgz",
+      "integrity": "sha512-AicPrAC7Qu1JxPCZ9ZgCZlY35QgFnNqc+0LtbRNxnVw4TXvjQ72wnuL9JQcEBgXkI9JM8MsT9kaQoHcpCRJOYA==",
+      "dev": true,
+      "requires": {
+        "path-parse": "^1.0.5"
+      }
+    },
     "safe-buffer": {
       "version": "5.1.2",
       "resolved": "https://registry.npmjs.org/safe-buffer/-/safe-buffer-5.1.2.tgz",
       "integrity": "sha512-Gd2UZBJDkXlY7GbJxfsE8/nvKkUEU1G38c1siN6QP6a9PT9MmHB8GnpscSmMJSoF8LOIrt8ud/wPtojys4G6+g==",
       "dev": true
     },
+    "semver": {
+      "version": "5.6.0",
+      "resolved": "https://registry.npmjs.org/semver/-/semver-5.6.0.tgz",
+      "integrity": "sha512-RS9R6R35NYgQn++fkDWaOmqGoj4Ek9gGs+DPxNUZKuwE183xjJroKvyo1IzVFeXvUrvmALy6FWD5xrdJT25gMg==",
+      "dev": true
+    },
     "smartchai": {
       "version": "2.0.1",
       "resolved": "https://registry.npmjs.org/smartchai/-/smartchai-2.0.1.tgz",
@@ -735,6 +879,15 @@
         "safe-buffer": "~5.1.0"
       }
     },
+    "strip-ansi": {
+      "version": "3.0.1",
+      "resolved": "http://registry.npmjs.org/strip-ansi/-/strip-ansi-3.0.1.tgz",
+      "integrity": "sha1-ajhfuIU9lS1f8F0Oiq+UJ43GPc8=",
+      "dev": true,
+      "requires": {
+        "ansi-regex": "^2.0.0"
+      }
+    },
     "strip-bom": {
       "version": "2.0.0",
       "resolved": "https://registry.npmjs.org/strip-bom/-/strip-bom-2.0.0.tgz",
@@ -763,6 +916,12 @@
         "strip-bom": "^2.0.0"
       }
     },
+    "supports-color": {
+      "version": "2.0.0",
+      "resolved": "https://registry.npmjs.org/supports-color/-/supports-color-2.0.0.tgz",
+      "integrity": "sha1-U10EXOa2Nj+kARcIRimZXp3zJMc=",
+      "dev": true
+    },
     "ts-node": {
       "version": "7.0.1",
       "resolved": "https://registry.npmjs.org/ts-node/-/ts-node-7.0.1.tgz",
@@ -779,6 +938,47 @@
         "yn": "^2.0.0"
       }
     },
+    "tslib": {
+      "version": "1.9.3",
+      "resolved": "https://registry.npmjs.org/tslib/-/tslib-1.9.3.tgz",
+      "integrity": "sha512-4krF8scpejhaOgqzBEcGM7yDIEfi0/8+8zDRZhNZZ2kjmHJ4hv3zCbQWxoJGz1iw5U0Jl0nma13xzHXcncMavQ==",
+      "dev": true
+    },
+    "tslint": {
+      "version": "5.11.0",
+      "resolved": "https://registry.npmjs.org/tslint/-/tslint-5.11.0.tgz",
+      "integrity": "sha1-mPMMAurjzecAYgHkwzywi0hYHu0=",
+      "dev": true,
+      "requires": {
+        "babel-code-frame": "^6.22.0",
+        "builtin-modules": "^1.1.1",
+        "chalk": "^2.3.0",
+        "commander": "^2.12.1",
+        "diff": "^3.2.0",
+        "glob": "^7.1.1",
+        "js-yaml": "^3.7.0",
+        "minimatch": "^3.0.4",
+        "resolve": "^1.3.2",
+        "semver": "^5.3.0",
+        "tslib": "^1.8.0",
+        "tsutils": "^2.27.2"
+      }
+    },
+    "tslint-config-prettier": {
+      "version": "1.17.0",
+      "resolved": "https://registry.npmjs.org/tslint-config-prettier/-/tslint-config-prettier-1.17.0.tgz",
+      "integrity": "sha512-NKWNkThwqE4Snn4Cm6SZB7lV5RMDDFsBwz6fWUkTxOKGjMx8ycOHnjIbhn7dZd5XmssW3CwqUjlANR6EhP9YQw==",
+      "dev": true
+    },
+    "tsutils": {
+      "version": "2.29.0",
+      "resolved": "https://registry.npmjs.org/tsutils/-/tsutils-2.29.0.tgz",
+      "integrity": "sha512-g5JVHCIJwzfISaXpXE1qvNalca5Jwob6FjI4AoPlqMusJ6ftFE7IkkFoMhVLRgK+4Kx3gkzb8UZK5t5yTTvEmA==",
+      "dev": true,
+      "requires": {
+        "tslib": "^1.8.1"
+      }
+    },
     "type-detect": {
       "version": "4.0.8",
       "resolved": "https://registry.npmjs.org/type-detect/-/type-detect-4.0.8.tgz",
diff --git a/package.json b/package.json
index dc63735..a240dcc 100644
--- a/package.json
+++ b/package.json
@@ -27,6 +27,8 @@
     "@gitzone/tsrun": "^1.1.12",
     "@gitzone/tstest": "^1.0.15",
     "@pushrocks/tapbundle": "^3.0.5",
-    "@types/node": "^10.9.4"
+    "@types/node": "^10.9.4",
+    "tslint": "^5.11.0",
+    "tslint-config-prettier": "^1.17.0"
   }
 }
diff --git a/test/test.ts b/test/test.ts
index 8bf245b..e5d2042 100644
--- a/test/test.ts
+++ b/test/test.ts
@@ -9,12 +9,12 @@ tap.test('should create an emitter ->', async () => {
   expect(myEventEmitter).to.be.instanceof(smartevent.EventEmitter);
 });
 
-tap.test('smartevent.once -> should return a promise', async () => {
-  let oncePromise = smartevent.once(myEventEmitter, 'customEvent');
+tap.test('smartevent.once -> should return a promise', async (tools) => {
+  const oncePromise = smartevent.once(myEventEmitter, 'customEvent');
   expect(oncePromise).to.be.instanceof(Promise);
-  expect(oncePromise).to.not.be.fulfilled;
-  myEventEmitter.emit('customEvent');
-  await expect(oncePromise).to.eventually.be.fulfilled;
+  expect(oncePromise).to.not.be.rejected;
+  myEventEmitter.emit('customEvent', 'hithere');
+  await expect(oncePromise).to.eventually.be.fulfilled.with.equal('hithere');
 });
 
 tap.start();
diff --git a/ts/index.ts b/ts/index.ts
index 951202e..0cc803d 100644
--- a/ts/index.ts
+++ b/ts/index.ts
@@ -3,8 +3,10 @@ import { EventEmitter } from 'events';
 
 export { EventEmitter };
 
-export let once = async <T>(eventEmitter: EventEmitter, eventName: string): Promise<T> => {
-  let done = plugins.smartpromise.defer<T>();
-  eventEmitter.once(eventName, done.resolve);
+export const once = async <T>(eventEmitter: EventEmitter, eventName: string): Promise<T> => {
+  const done = plugins.smartpromise.defer<T>();
+  eventEmitter.once(eventName, eventPayload => {
+    done.resolve(eventPayload);
+  });
   return await done.promise;
 };
diff --git a/tslint.json b/tslint.json
index 45052ad..d4ea2e9 100644
--- a/tslint.json
+++ b/tslint.json
@@ -1,3 +1,17 @@
 {
-    "extends": "tslint-config-standard"
+  "extends": ["tslint:latest", "tslint-config-prettier"],
+  "rules": {
+    "semicolon": [true, "always"],
+    "no-console": false,
+    "ordered-imports": false,
+    "object-literal-sort-keys": false,
+    "member-ordering": {
+      "options":{
+        "order": [
+          "static-method"
+        ]
+      }
+    }
+  },
+  "defaultSeverity": "warning"
 }