diff --git a/.babelrc b/.babelrc
index abe7e1ef3f..3710e20a37 100644
--- a/.babelrc
+++ b/.babelrc
@@ -1,20 +1,25 @@
 {
+    "sourceMaps": "inline",
     "presets": [
-        "react",
-        "es2015",
-        "es2016"
+        ["@babel/preset-env", {
+            "targets": {
+                "browsers": [
+                    "last 2 versions"
+                ],
+                "node": 12
+            },
+            "modules": "commonjs"
+        }],
+        "@babel/preset-typescript",
+        "@babel/preset-flow",
+        "@babel/preset-react"
     ],
     "plugins": [
-        [
-            "transform-builtin-extend",
-            {
-                "globals": ["Error"]
-            }
-        ],
-        "transform-class-properties",
-        "transform-object-rest-spread",
-        "transform-runtime",
-        "add-module-exports",
-        "syntax-dynamic-import"
+        "@babel/plugin-proposal-numeric-separator",
+        "@babel/plugin-proposal-class-properties",
+        "@babel/plugin-proposal-object-rest-spread",
+        "@babel/plugin-transform-flow-comments",
+        "@babel/plugin-syntax-dynamic-import",
+        "@babel/plugin-transform-runtime"
     ]
 }
diff --git a/.buildkite/pipeline.yaml b/.buildkite/pipeline.yaml
index be0d5e404c..8bbcdf78a4 100644
--- a/.buildkite/pipeline.yaml
+++ b/.buildkite/pipeline.yaml
@@ -1,13 +1,39 @@
 steps:
-  - label: ":eslint: Lint"
+  - label: ":eslint: JS Lint"
     command:
       - "echo '--- Install js-sdk'"
       - "./scripts/ci/install-deps.sh"
-      - "yarn lintwithexclusions"
-      - "yarn stylelint"
+      - "yarn lint:js"
     plugins:
       - docker#v3.0.1:
-          image: "node:10"
+          image: "node:12"
+
+  - label: ":eslint: TS Lint"
+    command:
+      - "echo '--- Install js-sdk'"
+      - "./scripts/ci/install-deps.sh"
+      - "yarn lint:ts"
+    plugins:
+      - docker#v3.0.1:
+          image: "node:12"
+
+  - label: ":eslint: Types Lint"
+    command:
+      - "echo '--- Install js-sdk'"
+      - "./scripts/ci/install-deps.sh"
+      - "yarn lint:types"
+    plugins:
+      - docker#v3.0.1:
+          image: "node:12"
+
+  - label: "🛠 Build"
+    command:
+      - "echo '--- Install js-sdk'"
+      - "./scripts/ci/install-deps.sh"
+      - "yarn build"
+    plugins:
+      - docker#v3.0.1:
+          image: "node:12"
 
   - label: ":chains: End-to-End Tests"
     agents:
diff --git a/karma.conf.js b/karma.conf.js
index d55be049bb..92e4e0e886 100644
--- a/karma.conf.js
+++ b/karma.conf.js
@@ -8,7 +8,7 @@ var fs = require('fs');
  * to build everything; however it's the easiest way to load our dependencies
  * from node_modules.
  *
- * If you run karma in multi-run mode (with `yarn test-multi`), it will watch
+ * If you run karma in multi-run mode (with `yarn test:multi`), it will watch
  * the tests for changes, and webpack will rebuild using a cache. This is much quicker
  * than a clean rebuild.
  */
diff --git a/package.json b/package.json
index 2f35ab7750..3b6e571d0c 100644
--- a/package.json
+++ b/package.json
@@ -8,10 +8,7 @@
     "url": "https://github.com/matrix-org/matrix-react-sdk"
   },
   "license": "Apache-2.0",
-  "main": "lib/index.js",
   "files": [
-    ".babelrc",
-    ".eslintrc.js",
     "CHANGELOG.md",
     "CONTRIBUTING.rst",
     "LICENSE",
@@ -19,14 +16,11 @@
     "code_style.md",
     "git-revision.txt",
     "header",
-    "jenkins.sh",
-    "karma.conf.js",
     "lib",
     "package.json",
-    "release.sh",
     "scripts",
+    "docs",
     "src",
-    "test",
     "res"
   ],
   "bin": {
@@ -34,32 +28,33 @@
     "matrix-gen-i18n": "scripts/gen-i18n.js",
     "matrix-prune-i18n": "scripts/prune-i18n.js"
   },
+  "main": "lib/index.js",
+  "typings": "lib/index.d.ts",
   "scripts": {
-    "reskindex": "node scripts/reskindex.js -h header",
-    "reskindex:watch": "node scripts/reskindex.js -h header -w",
-    "rethemendex": "res/css/rethemendex.sh",
     "i18n": "matrix-gen-i18n",
     "prunei18n": "matrix-prune-i18n",
     "diff-i18n": "cp src/i18n/strings/en_EN.json src/i18n/strings/en_EN_orig.json && ./scripts/gen-i18n.js && node scripts/compare-file.js src/i18n/strings/en_EN_orig.json src/i18n/strings/en_EN.json",
-    "build": "yarn reskindex && yarn start:init",
-    "build:watch": "babel src -w --skip-initial-build -d lib --source-maps --copy-files",
     "emoji-data-strip": "node scripts/emoji-data-strip.js",
-    "start": "yarn start:init && yarn start:all",
-    "start:all": "concurrently --kill-others-on-fail --prefix \"{time} [{name}]\" -n build,reskindex \"yarn build:watch\" \"yarn reskindex:watch\"",
-    "start:init": "babel src -d lib --source-maps --copy-files",
-    "lint": "eslint src/",
-    "lintall": "eslint src/ test/",
-    "lintwithexclusions": "eslint --max-warnings 0 --ignore-path .eslintignore.errorfiles src test",
-    "stylelint": "stylelint 'res/css/**/*.scss'",
+    "reskindex": "node scripts/reskindex.js -h header",
+    "reskindex:watch": "node scripts/reskindex.js -h header -w",
+    "rethemendex": "res/css/rethemendex.sh",
     "clean": "rimraf lib",
-    "prepare": "yarn clean && yarn build && git rev-parse HEAD > git-revision.txt",
+    "build": "yarn clean && git rev-parse HEAD > git-revision.txt && yarn build:compile && yarn build:types",
+    "build:compile": "yarn reskindex && babel src -s -d lib --verbose --extensions \".ts,.js\"",
+    "build:types": "tsc --emitDeclarationOnly",
+    "start": "echo THIS IS FOR LEGACY PURPOSES ONLY. && yarn start:all",
+    "start:all": "concurrently --kill-others-on-fail --prefix \"{time} [{name}]\" -n build,reskindex \"yarn start:build\" \"yarn reskindex:watch\"",
+    "start:build": "babel src -w -s -d lib --verbose --extensions \".ts,.js\"",
+    "lint": "yarn lint:types && yarn lint:ts && yarn lint:js && yarn lint:style",
+    "lint:js": "eslint --max-warnings 0 --ignore-path .eslintignore.errorfiles src test",
+    "lint:ts": "tslint --project ./tsconfig.json -t stylish",
+    "lint:types": "tsc --noEmit",
+    "lint:style": "stylelint 'res/css/**/*.scss'",
     "test": "karma start --single-run=true --browsers VectorChromeHeadless",
-    "test-multi": "karma start",
-    "e2etests": "./test/end-to-end-tests/run.sh --riot-url http://localhost:8080"
+    "test:multi": "karma start",
+    "test:e2e": "./test/end-to-end-tests/run.sh --riot-url http://localhost:8080"
   },
   "dependencies": {
-    "babel-plugin-syntax-dynamic-import": "^6.18.0",
-    "babel-runtime": "^6.26.0",
     "blueimp-canvas-to-blob": "^3.5.0",
     "browser-encrypt-attachment": "^0.3.0",
     "browser-request": "^0.3.3",
@@ -115,20 +110,20 @@
     "zxcvbn": "^4.4.2"
   },
   "devDependencies": {
-    "babel-cli": "^6.26.0",
-    "babel-core": "^6.26.3",
-    "babel-eslint": "^10.0.1",
-    "babel-loader": "^7.1.5",
-    "babel-plugin-add-module-exports": "^0.2.1",
-    "babel-plugin-transform-builtin-extend": "^1.1.2",
-    "babel-plugin-transform-class-properties": "^6.24.1",
-    "babel-plugin-transform-object-rest-spread": "^6.26.0",
-    "babel-plugin-transform-runtime": "^6.23.0",
-    "babel-polyfill": "^6.26.0",
-    "babel-preset-es2015": "^6.24.1",
-    "babel-preset-es2016": "^6.24.1",
-    "babel-preset-es2017": "^6.24.1",
-    "babel-preset-react": "^6.24.1",
+    "@babel/cli": "^7.7.5",
+    "@babel/core": "^7.7.5",
+    "@babel/plugin-proposal-class-properties": "^7.7.4",
+    "@babel/plugin-proposal-numeric-separator": "^7.7.4",
+    "@babel/plugin-proposal-object-rest-spread": "^7.7.4",
+    "@babel/plugin-transform-flow-comments": "^7.7.4",
+    "@babel/plugin-transform-runtime": "^7.7.6",
+    "@babel/preset-env": "^7.7.6",
+    "@babel/preset-flow": "^7.7.4",
+    "@babel/preset-react": "^7.7.4",
+    "@babel/preset-typescript": "^7.7.4",
+    "@babel/register": "^7.7.4",
+    "@babel/runtime": "^7.7.6",
+    "babel-eslint": "^10.0.3",
     "chokidar": "^2.1.2",
     "concurrently": "^4.0.1",
     "eslint": "^5.12.0",
@@ -163,6 +158,8 @@
     "stylelint": "^9.10.1",
     "stylelint-config-standard": "^18.2.0",
     "stylelint-scss": "^3.9.0",
+    "tslint": "^5.20.1",
+    "typescript": "^3.7.3",
     "walk": "^2.3.9",
     "webpack": "^4.20.2",
     "webpack-cli": "^3.1.1"