What Happens to My JavaScript at Runtime?

Part of: Questions & Answers · The Story of Morph

It becomes C++ — then machine code.

At build time, the TSToCppTranslator converts your component logic into C++ methods. Those methods are compiled with g++ into the app's logic module and linked into the binary. At runtime:

• No interpreter — nothing reads your JS as JS
• No JIT — there's no VM warming up at launch
• No VM — no V8, no Node, no JavaScript engine of any kind

// what you write:
const doubled = items.map(x => x * 2)

// becomes, effectively:
for (auto& x : items) { doubled.push_back(x * 2); }

The practical result: your component logic runs at the speed of compiled C++. Property access, loops, arithmetic, function calls — all direct machine instructions, not interpreted dispatch. That's the performance story behind "your logic is native code."

This only works because the compiler covers the TypeScript/JavaScript you actually write. That's why TS→C++ Translator Coverage is a priority — every language feature the translator covers is one more thing you can use and still get native speed.