deno VS v8.dev

NodeJS is the dominant Javascript server runtime environment for Javascript and Typescript (sort of) projects. But over the years, we have seen several attempts to build alternative runtime environments such as Deno and Bun, today’s subject, among others.

https://github.com/denoland/deno/issues is the ideal place -- we try to triage all incoming issues, the more specific the repro the easier it is to address but we will take a look at everything that comes in.

Install Node.js (or Bun, or Deno, or whatever JS runtime you prefer) if it's not there

QUIC is very exciting, after seeing what it can do for performance in Cloudflare network and Cloudflare workers, I can't wait to finally see it in Deno[0] 1.41.

[0] https://github.com/denoland/deno/pull/21942#issuecomment-192...

So as an end user it's kind of like https://deno.com/ where you buy into a runtime + comes prepacked with DBs (k/v stores), scheduling, and deploy stuff?

> by storing Unison code in a database, keyed by the hash of that code, we gain a perfect incremental compilation cache which is shared among all developers of a project. This is an absolutely WILD feature, but it's fantastic and hard to go back once you've experienced it. I am basically never waiting around for my code to compile - once code has been parsed and typechecked once, by anyone, it's not touched again until it's changed.

Interesting. Whats it like upgrading and managing dependencies in that code? I'd assume it gets more complex when it's not just the Union system but 3rd party plugins (stuff interacting with the OS or other libs).

~90MB+ at this stage and do now allow compression without erroring out. Deploying ala Golang is not feasible at that level but could well be down the line if this dev branch is picked up again!

The exe output grew from from ~50MB to plus ~90MB from 2021 to 2024: https://github.com/denoland/deno/discussions/9811 which mean Deno is worse than Node.js's pkg solution by a decent margin.

Behind the scenes is a simple Sveltekit-powered server function to fetch a Spotify client token then find a user's recommendation playlist and its track information. A Deno edge function to performs this data fetch and renders server-side Svelte.

If your application is written in JavaScript, integrating it with JavaScript extensions is a no-brainer. However, Secutils.dev is entirely written in Rust. How would I even begin? Fortunately, I recently came across an excellent blog post series explaining how to implement your JavaScript runtime in a Rust application with Deno:

Semi-related - I saw this trick on https://v8.dev a while back, but `filter: hue-rotate(180deg) invert();` can be a neat CSS trick to 'dark mode' some kinds of graphics. The `hue-rotate` help a bit to keep 'blues blue' etc.

It's far from perfect, but it's a neat trick to be aware of.

V8 is a high-performance JavaScript engine developed by Google. Its purpose is to convert JavaScript code into machine code for execution by the underlying hardware. Primarily developed by the V8 team at Google, the engine focuses on speed and efficiency. In particular, it relies on just-in-time compilation and uses inline caching for high performance.

V8

Exactly the same as JavaScript engines. Be it Mozilla's SpiderMoneky, Google's V8, Apple's Webkit, or Microsoft's Chakra. No matter how specific we draft a specification there is always room for interpretation. Every team has a different take on what part of a spec is describing. Oftentimes it's just a matter of varying pros and cons of different approaches on the road to matching spec; various teams just kind of have to pick a direction and run with it. Other times a spec is not only too vague, but clearly short-sighted to boot.

Remember that we earlier established that every source gets parsed into an AST at some point before it gets compiled or interpreted. For example, platforms like Nodejs and chromium-based browsers use Gooogle's V8 engine behind the scenes to run JavaScript and of course, some AST parsing is always involved before the interpreter kicks in. I looked V8's source and I discovered it uses its own internal parser to achieve this.

While Node.js uses Google's V8 engine that power's Chrome browser, Bun uses JavaScriptCore (JSC), which is an open source JavaScript engine developed by Apple for Safari.

While the idea of server-side JavaScript was not novel, what powered Node.js was! The V8 engine, birthed by Google for Chrome, was now driving Node.js, bringing unparalleled speed and performance to JavaScript execution.

V8 JavaScript Engine

Node runs on the V8 JavaScript engine, which handles memory allocation. The entirety of memory used for a running Node application is held in what is known as a Resident Set. This includes: