TypeScript vs JavaScript

JavaScript vs TypeScript — Which one actually fits your project?
This video cuts through the hype and looks at trade-offs, not tribes. We unpack the “extra build step” argument, why TypeScript’s type inference lowers the learning curve, how abusing any leads to TINO (TypeScript In Name Only), why tests and TS aren’t substitutes but partners, the vendor lock-in myth (TS compiles to plain JS), and where runtime safety really comes from (validation, guards—TS is your co-pilot, not an airbag). We also outline when TS is overkill and when plain JS is perfectly sensible.

What you’ll learn

How a small compile step compares to the unmanaged complexity of growing apps

Why most devs don’t need to write tons of types (thanks to inference)

The real cost of sprinkling any and how it spreads through a codebase (TINO)

TS vs tests = wrong question—use both for different kinds of errors

Why TypeScript isn’t vendor lock-in (output is standard JavaScript)

Runtime safety: null/undefined, await, and input validation are still on you

Clear criteria for choosing JS or TS based on team size, lifespan, velocity, safety

Example from the video

function calculateTotal(price: number, quantity: number): number {
return price / quantity; // Bug! Should be *
}


Perfectly typed, logically wrong—tests catch this, not the type system.

Who this is for

Teams stuck between “move fast in JS” and “stabilize with TS”

Codebases drifting toward any and weak contracts

Engineers designing a sustainable path from MVP → growth → scale

Resources mentioned

TypeScript docs

ESLint + Prettier with TS

Runtime validation (e.g., Zod)

Join the conversation
What criteria matter most in your context—Team Size, Lifespan, Velocity, Safety? Drop a comment.

Hashtags
#JavaScript #TypeScript #WebDevelopment #SoftwareEngineering #CleanCode #Testing #Frontend #NodeJS #Programming #DevTools

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