diff --git a/.gitignore b/.gitignore
index 2109e19..0eedb72 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 build
 node_modules
 package-lock.json
+src/react-app-env.d.ts
diff --git a/package.json b/package.json
index 8870b04..369d728 100644
--- a/package.json
+++ b/package.json
@@ -29,14 +29,14 @@
     "@types/react-router-dom": "^4.3.1",
     "gh-pages": "^2.0.1",
     "prettier": "^1.15.3",
-    "react-scripts-ts": "^4.0.8",
+    "react-scripts": "^2.1.3",
     "tslint-config-prettier": "^1.17.0",
     "typescript": "latest"
   },
   "scripts": {
-    "start": "react-scripts-ts start",
-    "build": "react-scripts-ts build",
-    "test": "react-scripts-ts test --env=jsdom",
+    "start": "react-scripts start",
+    "build": "react-scripts build",
+    "test": "react-scripts test --env=jsdom",
     "prettier": "prettier --write src/**/*.{ts,tsx,json}",
     "predeploy": "npm run build",
     "deploy": "gh-pages -d build"
diff --git a/src/chart.tsx b/src/chart.tsx
index b01a873..408fb1a 100644
--- a/src/chart.tsx
+++ b/src/chart.tsx
@@ -20,7 +20,7 @@ function zoomed() {
 /** Called when the scrollbars are used. */
 function scrolled() {
   const svg = d3.select('#chart');
-  const parent = (svg.node() as HTMLElement).parentElement!;
+  const parent = (svg.node() as HTMLElement).parentElement as Element;
   const x = parent.scrollLeft + parent.clientWidth / 2;
   const y = parent.scrollTop + parent.clientHeight / 2;
   d3.select(parent).call(d3.zoom().translateTo, x, y);
@@ -59,7 +59,7 @@ export class Chart extends React.PureComponent<ChartProps, {}> {
       baseGeneration: this.props.selection.generation,
     });
     const svg = d3.select('#chart');
-    const parent = (svg.node() as HTMLElement).parentElement!;
+    const parent = (svg.node() as HTMLElement).parentElement as Element;
 
     d3.select(parent)
       .on('scroll', scrolled)
diff --git a/src/chart_view.tsx b/src/chart_view.tsx
index 8b7efc5..6eaa337 100644
--- a/src/chart_view.tsx
+++ b/src/chart_view.tsx
@@ -1,7 +1,7 @@
-import * as md5 from 'md5';
 import * as queryString from 'query-string';
 import * as React from 'react';
 import axios from 'axios';
+import md5 from 'md5';
 import {Chart} from './chart';
 import {convertGedcom} from './gedcom_util';
 import {IndiInfo, JsonGedcomData} from 'topola';
diff --git a/src/index.tsx b/src/index.tsx
index 51ad9c2..3a822c3 100644
--- a/src/index.tsx
+++ b/src/index.tsx
@@ -1,8 +1,8 @@
 import * as locale_en from 'react-intl/locale-data/en';
 import * as locale_pl from 'react-intl/locale-data/pl';
-import * as messages_pl from './translations/pl.json';
 import * as React from 'react';
 import * as ReactDOM from 'react-dom';
+import messages_pl from './translations/pl.json';
 import {addLocaleData} from 'react-intl';
 import {ChartView} from './chart_view';
 import {HashRouter as Router, Route, Switch} from 'react-router-dom';
diff --git a/src/top_bar.tsx b/src/top_bar.tsx
index 010f32a..3402def 100644
--- a/src/top_bar.tsx
+++ b/src/top_bar.tsx
@@ -1,6 +1,6 @@
-import * as md5 from 'md5';
 import * as queryString from 'query-string';
 import * as React from 'react';
+import md5 from 'md5';
 import {FormattedMessage} from 'react-intl';
 import {Link} from 'react-router-dom';
 import {RouteComponentProps} from 'react-router-dom';
diff --git a/tsconfig.json b/tsconfig.json
index 3e852eb..4c0ca24 100644
--- a/tsconfig.json
+++ b/tsconfig.json
@@ -1,32 +1,25 @@
 {
   "compilerOptions": {
-    "baseUrl": ".",
-    "outDir": "build/dist",
-    "module": "esnext",
     "target": "es5",
-    "lib": ["es6", "dom"],
-    "sourceMap": true,
+    "lib": [
+      "dom",
+      "esnext"
+    ],
     "allowJs": true,
-    "jsx": "react",
-    "moduleResolution": "node",
-    "rootDir": "src",
-    "types": [],
+    "skipLibCheck": true,
+    "esModuleInterop": true,
+    "strict": true,
     "forceConsistentCasingInFileNames": true,
-    "noImplicitReturns": true,
-    "noImplicitThis": true,
-    "noImplicitAny": true,
-    "strictNullChecks": true,
-    "suppressImplicitAnyIndexErrors": true,
-    "noUnusedLocals": true,
-    "resolveJsonModule": true
+    "module": "esnext",
+    "moduleResolution": "node",
+    "resolveJsonModule": true,
+    "isolatedModules": true,
+    "noEmit": true,
+    "jsx": "preserve",
+    "allowSyntheticDefaultImports": true,
+    "suppressImplicitAnyIndexErrors": true
   },
-  "exclude": [
-    "node_modules",
-    "build",
-    "scripts",
-    "acceptance-tests",
-    "webpack",
-    "jest",
-    "src/setupTests.ts"
+  "include": [
+    "src"
   ]
 }
diff --git a/tsconfig.prod.json b/tsconfig.prod.json
deleted file mode 100644
index 714d1cd..0000000
--- a/tsconfig.prod.json
+++ /dev/null
@@ -1 +0,0 @@
-{ "extends": "./tsconfig.json" }