diff --git a/demo/gl-bench.js b/demo/gl-bench.js
index 66ceed95..72ffffcb 100644
--- a/demo/gl-bench.js
+++ b/demo/gl-bench.js
@@ -1,4 +1,3 @@
-// @ts-nocheck
 /* eslint-disable max-len */
 
 // based on: https://github.com/munrocket/gl-bench
diff --git a/demo/menu.js b/demo/menu.js
index fa16af5e..3eeac1f6 100644
--- a/demo/menu.js
+++ b/demo/menu.js
@@ -1,5 +1,3 @@
-// @ts-nocheck
-
 let instance = 0;
 let CSScreated = false;
 
diff --git a/package.json b/package.json
index 95ae6f87..a330369a 100644
--- a/package.json
+++ b/package.json
@@ -46,7 +46,7 @@
     "seedrandom": "^3.0.5",
     "simple-git": "^2.34.2",
     "tslib": "^2.1.0",
-    "typescript": "^4.1.3"
+    "typescript": "^4.2.0-dev.20210208"
   },
   "scripts": {
     "start": "node --trace-warnings --unhandled-rejections=strict --trace-uncaught --no-deprecation src/node.js",
diff --git a/src/age/age.ts b/src/age/age.ts
index 1428f00d..3b8deac9 100644
--- a/src/age/age.ts
+++ b/src/age/age.ts
@@ -2,20 +2,20 @@ import { log } from '../log';
 import * as tf from '../../dist/tfjs.esm.js';
 import * as profile from '../profile.js';
 
-const models = { age: null };
+let model;
 let last = { age: 0 };
 let skipped = Number.MAX_SAFE_INTEGER;
 
 export async function load(config) {
-  if (!models.age) {
-    models.age = await tf.loadGraphModel(config.face.age.modelPath);
+  if (!model) {
+    model = await tf.loadGraphModel(config.face.age.modelPath);
     log(`load model: ${config.face.age.modelPath.match(/\/(.*)\./)[1]}`);
   }
-  return models.age;
+  return model;
 }
 
 export async function predict(image, config) {
-  if (!models.age) return null;
+  if (!model) return null;
   if ((skipped < config.face.age.skipFrames) && config.videoOptimized && last.age && (last.age > 0)) {
     skipped++;
     return last;
@@ -38,27 +38,25 @@ export async function predict(image, config) {
     tf.dispose(resize);
 
     let ageT;
-    const obj = { age: undefined };
+    const obj = { age: 0 };
 
-    if (models.age) {
-      if (!config.profile) {
-        if (config.face.age.enabled) ageT = await models.age.predict(enhance);
-      } else {
-        const profileAge = config.face.age.enabled ? await tf.profile(() => models.age.predict(enhance)) : {};
-        ageT = profileAge.result.clone();
-        profileAge.result.dispose();
-        profile.run('age', profileAge);
-      }
-      enhance.dispose();
-
-      if (ageT) {
-        const data = ageT.dataSync();
-        obj.age = Math.trunc(10 * data[0]) / 10;
-      }
-      ageT.dispose();
-
-      last = obj;
+    if (!config.profile) {
+      if (config.face.age.enabled) ageT = await model.predict(enhance);
+    } else {
+      const profileAge = config.face.age.enabled ? await tf.profile(() => model.predict(enhance)) : {};
+      ageT = profileAge.result.clone();
+      profileAge.result.dispose();
+      profile.run('age', profileAge);
     }
+    enhance.dispose();
+
+    if (ageT) {
+      const data = ageT.dataSync();
+      obj.age = Math.trunc(10 * data[0]) / 10;
+    }
+    ageT.dispose();
+
+    last = obj;
     resolve(obj);
   });
 }
diff --git a/src/emotion/emotion.ts b/src/emotion/emotion.ts
index 4bdd01da..99cc9968 100644
--- a/src/emotion/emotion.ts
+++ b/src/emotion/emotion.ts
@@ -3,8 +3,8 @@ import * as tf from '../../dist/tfjs.esm.js';
 import * as profile from '../profile.js';
 
 const annotations = ['angry', 'disgust', 'fear', 'happy', 'sad', 'surprise', 'neutral'];
-const models = { emotion: null };
-let last = [];
+let model;
+let last: Array<{ score: number, emotion: string }> = [];
 let skipped = Number.MAX_SAFE_INTEGER;
 
 // tuning values
@@ -12,15 +12,15 @@ const rgb = [0.2989, 0.5870, 0.1140]; // factors for red/green/blue colors when
 const scale = 1; // score multiplication factor
 
 export async function load(config) {
-  if (!models.emotion) {
-    models.emotion = await tf.loadGraphModel(config.face.emotion.modelPath);
+  if (!model) {
+    model = await tf.loadGraphModel(config.face.emotion.modelPath);
     log(`load model: ${config.face.emotion.modelPath.match(/\/(.*)\./)[1]}`);
   }
-  return models.emotion;
+  return model;
 }
 
 export async function predict(image, config) {
-  if (!models.emotion) return null;
+  if (!model) return null;
   if ((skipped < config.face.emotion.skipFrames) && config.videoOptimized && (last.length > 0)) {
     skipped++;
     return last;
@@ -54,15 +54,15 @@ export async function predict(image, config) {
     blueNorm.dispose();
     const normalize = tf.tidy(() => grayscale.sub(0.5).mul(2));
     grayscale.dispose();
-    const obj = [];
+    const obj: Array<{ score: number, emotion: string }> = [];
     if (config.face.emotion.enabled) {
       let data;
       if (!config.profile) {
-        const emotionT = await models.emotion.predict(normalize);
+        const emotionT = await model.predict(normalize);
         data = emotionT.dataSync();
         tf.dispose(emotionT);
       } else {
-        const profileData = await tf.profile(() => models.emotion.predict(normalize));
+        const profileData = await tf.profile(() => model.predict(normalize));
         data = profileData.result.dataSync();
         profileData.result.dispose();
         profile.run('emotion', profileData);
diff --git a/src/gender/gender.ts b/src/gender/gender.ts
index ca0282c0..d905bf04 100644
--- a/src/gender/gender.ts
+++ b/src/gender/gender.ts
@@ -2,7 +2,7 @@ import { log } from '../log';
 import * as tf from '../../dist/tfjs.esm.js';
 import * as profile from '../profile.js';
 
-const models = { gender: null };
+let model;
 let last = { gender: '' };
 let skipped = Number.MAX_SAFE_INTEGER;
 let alternative = false;
@@ -11,16 +11,16 @@ let alternative = false;
 const rgb = [0.2989, 0.5870, 0.1140]; // factors for red/green/blue colors when converting to grayscale
 
 export async function load(config) {
-  if (!models.gender) {
-    models.gender = await tf.loadGraphModel(config.face.gender.modelPath);
-    alternative = models.gender.inputs[0].shape[3] === 1;
+  if (!model) {
+    model = await tf.loadGraphModel(config.face.gender.modelPath);
+    alternative = model.inputs[0].shape[3] === 1;
     log(`load model: ${config.face.gender.modelPath.match(/\/(.*)\./)[1]}`);
   }
-  return models.gender;
+  return model;
 }
 
 export async function predict(image, config) {
-  if (!models.gender) return null;
+  if (!model) return null;
   if ((skipped < config.face.gender.skipFrames) && config.videoOptimized && last.gender !== '') {
     skipped++;
     return last;
@@ -45,12 +45,12 @@ export async function predict(image, config) {
     tf.dispose(resize);
 
     let genderT;
-    const obj = { gender: undefined, confidence: undefined };
+    const obj = { gender: '', confidence: 0 };
 
     if (!config.profile) {
-      if (config.face.gender.enabled) genderT = await models.gender.predict(enhance);
+      if (config.face.gender.enabled) genderT = await model.predict(enhance);
     } else {
-      const profileGender = config.face.gender.enabled ? await tf.profile(() => models.gender.predict(enhance)) : {};
+      const profileGender = config.face.gender.enabled ? await tf.profile(() => model.predict(enhance)) : {};
       genderT = profileGender.result.clone();
       profileGender.result.dispose();
       profile.run('gender', profileGender);
diff --git a/src/gesture/gesture.ts b/src/gesture/gesture.ts
index 617b8154..a966158a 100644
--- a/src/gesture/gesture.ts
+++ b/src/gesture/gesture.ts
@@ -1,6 +1,6 @@
 export const body = (res) => {
   if (!res) return [];
-  const gestures = [];
+  const gestures: Array<{ body: number, gesture: string }> = [];
   for (let i = 0; i < res.length; i++) {
     // raising hands
     const leftWrist = res[i].keypoints.find((a) => (a.part === 'leftWrist'));
@@ -20,7 +20,7 @@ export const body = (res) => {
 
 export const face = (res) => {
   if (!res) return [];
-  const gestures = [];
+  const gestures: Array<{ face: number, gesture: string }> = [];
   for (let i = 0; i < res.length; i++) {
     if (res[i].mesh && res[i].mesh.length > 0) {
       const eyeFacing = res[i].mesh[35][2] - res[i].mesh[263][2];
@@ -41,7 +41,7 @@ export const face = (res) => {
 
 export const iris = (res) => {
   if (!res) return [];
-  const gestures = [];
+  const gestures: Array<{ iris: number, gesture: string }> = [];
   for (let i = 0; i < res.length; i++) {
     if (!res[i].annotations || !res[i].annotations.leftEyeIris || !res[i].annotations.rightEyeIris) continue;
     const sizeXLeft = res[i].annotations.leftEyeIris[3][0] - res[i].annotations.leftEyeIris[1][0];
@@ -60,10 +60,11 @@ export const iris = (res) => {
 
 export const hand = (res) => {
   if (!res) return [];
-  const gestures = [];
+  const gestures: Array<{ hand: number, gesture: string }> = [];
   for (let i = 0; i < res.length; i++) {
-    const fingers = [];
+    const fingers: Array<{ name: string, position: number }>  = [];
     for (const [finger, pos] of Object.entries(res[i]['annotations'])) {
+      // @ts-ignore
       if (finger !== 'palmBase') fingers.push({ name: finger.toLowerCase(), position: pos[0] }); // get tip of each finger
     }
     if (fingers && fingers.length > 0) {
diff --git a/src/handpose/handdetector.ts b/src/handpose/handdetector.ts
index 2f443237..043d945b 100644
--- a/src/handpose/handdetector.ts
+++ b/src/handpose/handdetector.ts
@@ -49,7 +49,7 @@ export class HandDetector {
 
     scoresT.dispose();
     filteredT.dispose();
-    const hands = [];
+    const hands: Array<{ box: any, palmLandmarks: any, confidence: number }>  = [];
     for (const index of filtered) {
       if (scores[index] >= config.hand.minConfidence) {
         const matchingBox = tf.slice(boxes, [index, 0], [1, -1]);
@@ -70,7 +70,7 @@ export class HandDetector {
     const image = tf.tidy(() => input.resizeBilinear([config.hand.inputSize, config.hand.inputSize]).div(127.5).sub(1));
     const predictions = await this.getBoxes(image, config);
     image.dispose();
-    const hands = [];
+    const hands: Array<{}>  = [];
     if (!predictions || predictions.length === 0) return hands;
     for (const prediction of predictions) {
       const boxes = prediction.box.dataSync();
diff --git a/src/handpose/handpipeline.ts b/src/handpose/handpipeline.ts
index 0e1ed088..be2c995b 100644
--- a/src/handpose/handpipeline.ts
+++ b/src/handpose/handpipeline.ts
@@ -91,7 +91,7 @@ export class HandPipeline {
       // for (const possible of boxes) this.storedBoxes.push(possible);
       if (this.storedBoxes.length > 0) useFreshBox = true;
     }
-    const hands = [];
+    const hands: Array<{}> = [];
     // log('hand', `skipped: ${this.skipped} max: ${config.hand.maxHands} detected: ${this.detectedHands} stored: ${this.storedBoxes.length} new: ${boxes?.length}`);
 
     // go through working set of boxes
@@ -124,10 +124,7 @@ export class HandPipeline {
           const result = {
             landmarks: coords,
             confidence,
-            box: {
-              topLeft: nextBoundingBox.startPoint,
-              bottomRight: nextBoundingBox.endPoint,
-            },
+            box: { topLeft: nextBoundingBox.startPoint, bottomRight: nextBoundingBox.endPoint },
           };
           hands.push(result);
         } else {
@@ -139,10 +136,7 @@ export class HandPipeline {
         const enlarged = box.enlargeBox(box.squarifyBox(currentBox), HAND_BOX_ENLARGE_FACTOR);
         const result = {
           confidence: currentBox.confidence,
-          box: {
-            topLeft: enlarged.startPoint,
-            bottomRight: enlarged.endPoint,
-          },
+          box: { topLeft: enlarged.startPoint, bottomRight: enlarged.endPoint },
         };
         hands.push(result);
       }
diff --git a/src/handpose/handpose.ts b/src/handpose/handpose.ts
index de9dd60d..3f7a475b 100644
--- a/src/handpose/handpose.ts
+++ b/src/handpose/handpose.ts
@@ -29,7 +29,7 @@ export class HandPose {
   async estimateHands(input, config) {
     const predictions = await this.handPipeline.estimateHands(input, config);
     if (!predictions) return [];
-    const hands = [];
+    const hands: Array<{ confidence: number, box: any, landmarks: any, annotations: any }> = [];
     for (const prediction of predictions) {
       const annotations = {};
       if (prediction.landmarks) {
@@ -43,12 +43,7 @@ export class HandPose {
         Math.min(input.shape[2], prediction.box.bottomRight[0]) - prediction.box.topLeft[0],
         Math.min(input.shape[1], prediction.box.bottomRight[1]) - prediction.box.topLeft[1],
       ] : 0;
-      hands.push({
-        confidence: prediction.confidence,
-        box,
-        landmarks: prediction.landmarks,
-        annotations,
-      });
+      hands.push({ confidence: prediction.confidence, box, landmarks: prediction.landmarks, annotations });
     }
     return hands;
   }
diff --git a/src/human.ts b/src/human.ts
index 1816595d..301fe3f1 100644
--- a/src/human.ts
+++ b/src/human.ts
@@ -236,7 +236,7 @@ class Human {
     let genderRes;
     let emotionRes;
     let embeddingRes;
-    const faceRes = [];
+    const faceRes: Array<{ confidence: number, box: any, mesh: any, meshRaw: any, boxRaw: any, annotations: any, age: number, gender: string, genderConfidence: number, emotion: string, embedding: any, iris: number }> = [];
     this.state = 'run:face';
     timeStamp = now();
     const faces = await this.models.face?.estimateFaces(input, this.config);
@@ -349,8 +349,8 @@ class Human {
     this.state = 'image';
     this.config = mergeDeep(this.config, userConfig);
     const process = image.process(input, this.config);
-    process.tensor.dispose();
-    return process.canvas;
+    process?.tensor?.dispose();
+    return process?.canvas;
   }
 
   // main detect function
@@ -445,6 +445,7 @@ class Human {
       let gestureRes = [];
       if (this.config.gesture.enabled) {
         timeStamp = now();
+        // @ts-ignore
         gestureRes = [...gesture.face(faceRes), ...gesture.body(poseRes), ...gesture.hand(handRes), ...gesture.iris(faceRes)];
         if (!this.config.async) this.perf.gesture = Math.trunc(now() - timeStamp);
         else if (this.perf.gesture) delete this.perf.gesture;
@@ -495,8 +496,8 @@ class Human {
         canvas.width = size;
         canvas.height = size;
         const ctx = canvas.getContext('2d');
-        ctx.drawImage(img, 0, 0);
-        const data = ctx.getImageData(0, 0, size, size);
+        ctx?.drawImage(img, 0, 0);
+        const data = ctx?.getImageData(0, 0, size, size);
         this.detect(data, this.config).then((res) => resolve(res));
       };
       if (src) img.src = src;
diff --git a/src/image.ts b/src/image.ts
index b9cfe7bc..bb5e11bb 100644
--- a/src/image.ts
+++ b/src/image.ts
@@ -1,3 +1,5 @@
+// @ts-nocheck
+
 import { log } from './log';
 import * as tf from '../dist/tfjs.esm.js';
 import * as fxImage from './imagefx';
diff --git a/src/tfjs/backend.ts b/src/tfjs/backend.ts
index 293cd99f..799394cf 100644
--- a/src/tfjs/backend.ts
+++ b/src/tfjs/backend.ts
@@ -24,12 +24,14 @@ export function register() {
   if (!tf.findBackend(config.name)) {
     log('backend registration:', config.name);
     try {
+      // @ts-ignore
       config.canvas = (typeof OffscreenCanvas !== 'undefined') ? new OffscreenCanvas(config.width, config.height) : document.createElement('canvas');
     } catch (err) {
       log('error: cannot create canvas:', err);
       return;
     }
     try {
+      // @ts-ignore
       config.gl = config.canvas.getContext('webgl2', config.webGLattr);
     } catch (err) {
       log('error: cannot get WebGL2 context:', err);
@@ -60,6 +62,7 @@ export function register() {
     }
     try {
       tf.ENV.set('WEBGL_VERSION', 2);
+      // @ts-ignore
       tf.ENV.set('WEBGL_MAX_TEXTURE_SIZE', config.gl.getParameter(config.gl.MAX_TEXTURE_SIZE));
       tf.ENV.set('WEBGL_FORCE_F16_TEXTURES', true);
       tf.ENV.set('WEBGL_PACK_DEPTHWISECONV', true);
diff --git a/tsconfig.json b/tsconfig.json
index d32914d3..23f737ea 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -17,9 +17,9 @@
     "resolveJsonModule": true,
     "skipLibCheck": true,
     "sourceMap": false,
-    "strictNullChecks": false,
+    "strictNullChecks": true,
     "allowJs": true
   },
   "formatCodeOptions": { "indentSize": 2, "tabSize": 2 },
-  "include": ["src/*", "demo/*"],
+  "include": ["src/*", "src/***/*", "demo/*"],
 }
diff --git a/wiki b/wiki
index d8804390..d365c4e4 160000
--- a/wiki
+++ b/wiki
@@ -1 +1 @@
-Subproject commit d88043901df1d671a0897275bae8d0f537b84ff5
+Subproject commit d365c4e487508181811ea7ff1a26d682ef6896b7