JavaScript: The Pandemic That Escaped the Browser Quarantine

The Original Sin

• •Run servers
• •Build desktop applications
• •Power databases
• •Control robots
• •Run machine learning models
• •Compile operating systems
• •Replace every other programming language in existence

The Node.js Disaster of 2009

The Async Nightmare

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// What we write
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async function getUser() {
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  const user = await db.query('SELECT * FROM users');
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  return user;
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}
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// What we mean
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function getUser() {
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  return db.query('SELECT * FROM users');
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}
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// What actually happens
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function getUser() {
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  return new Promise((resolve, reject) => {
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    db.query('SELECT * FROM users', (err, result) => {
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      if (err) reject(err);
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      else resolve(result);
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    });
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  });
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}

The TypeScript Cope

• •A compiler
• •A config file with 200 options
• •Type definition files for every library
• •To understand generics, union types, intersection types, mapped types, conditional types, template literal types...
• •To debug why string | undefined isn't assignable to string | null | undefined
• •To realize the types are A LIE and disappear at runtime

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// Your beautiful TypeScript
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function add(a: number, b: number): number {
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  return a + b;
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}
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// What actually runs
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function add(a, b) {
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  return a + b;  // Hope those are numbers! 🤞
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}

NPM: The Dependency Hellscape

The "Everything Is JavaScript" Cult

• •Operating Systems? Node OS!
• •Databases? CouchDB, MongoDB!
• •Desktop apps? Electron! (aka Chrome in a trenchcoat)
• •Mobile apps? React Native! Ionic!
• •Machine Learning? TensorFlow.js!
• •Game engines? Three.js!
• •IoT? Johnny-Five!
• •Blockchain? Of course!

The Framework Churn Apocalypse

The Backend Abomination

• •Predictable performance
• •Strong typing
• •Proper threading
• •Sane error handling
• •Memory efficiency

• •"Performance depends on the phase of the moon"
• •"Types are a social construct"
• •"Single threaded but don't worry we have workers now!"
• •"Just try/catch everything bro"
• •"What's a memory leak?" leaks memory

The "Isomorphic" Delusion

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if (typeof window !== 'undefined') {
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  // Browser code
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} else {
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  // Node code
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}

The Real Tragedy

• •Python: Clean, readable, huge ecosystem
• •Ruby: Expressive, developer-friendly
• •Go: Fast, simple, built for servers
• •Rust: Safe, fast, modern
• •Hell, even PHP: Designed for the web!

• •Has == and === because equality is complicated
• •Thinks [] + [] = ""
• •Believes {} + {} = NaN
• •Contains the unholy trinity of null, undefined, and NaN
• •Has 'this' that changes based on how you call a function
• •Coerces types like a drunk magician

The Event Loop Excuse

We Did This To Ourselves

In Conclusion

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// What we write in Node.js
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const user = await getUser();
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const profile = await getProfile(user.id);
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const posts = await getPosts(profile.id);
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// What we actually want (and what other languages give us)
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user = getUser()
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profile = getProfile(user.id)
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posts = getPosts(profile.id)

• •Gigabyte-sized node_modules
• •TypeScript configuration hell
• •Async/await spaghetti
• •Framework churn fatigue
• •The heat death of software quality