JS compiled language

#javascript #beginners

The history teaches us that the compiler processes the code in three stages:

Lexing

As in the image above, in this phase, we convert our program into meaningful tokens.

Parsing

Here we take a stream of tokens (array) and trasform it into an abstract syntax tree called AST that represent the grammatical structure of the program.

Code Generation

Here JavaScript convert AST into a set of machine instruction.
Between parsing and code generation, JavaScript optimizes performance, execution and does also other cool stuff, all in a millisecond.
If you want take time to understand JavaScript engines look this awesome video from JS config Franziska Hinkelmann

How to reduce TTFB

In the past few years in the web dev world, we’ve seen a significant push towards rendering our websites on the server. Doing so is better for SEO and performs better on low-powered devices, but one thing we had to sacrifice is TTFB.

In this article, we’ll see how we can identify what makes our TTFB high so we can fix it.