Deno Bundle: Use Rolldown instead of ESBuild

[VienDinhCom]

Hey Deno Team!

As fans of Deno’s mission to simplify and secure JavaScript development, we think it’s time to consider Rolldown as your go-to bundler over ESBuild. Here’s why Rolldown could supercharge Deno’s ecosystem:

Blazing Fast Performance: Rolldown, built in Rust, matches ESBuild’s speed but often surpasses it, especially in WebAssembly builds. It’s 10-30x faster than Rollup, making it a powerhouse for large-scale projects. Faster builds mean happier devs!

Rollup-Compatible API: Rolldown’s API aligns with Rollup, ensuring seamless integration with Vite’s ecosystem and plugins. This compatibility reduces friction for Deno users building web apps.

Enhanced Features for Web Apps: Rolldown supports advanced features like code-splitting and CSS handling out of the box, addressing ESBuild’s limitations (e.g., weak code-splitting support). This makes it ideal for Deno’s web-focused projects, reducing configuration headaches.

Future-Proof Ecosystem: Designed for Vite but versatile as a standalone bundler, Rolldown is actively developed with a focus on modern JS/TS needs. It avoids ESBuild’s maintenance challenges, like sporadic plugin updates, ensuring long-term reliability for Deno’s community.

Community Momentum: The JavaScript world is buzzing about Rolldown. Adopting it could position Deno as a leader in cutting-edge tooling, attracting more devs to your ecosystem.

Deno’s philosophy of simplicity and performance aligns perfectly with Rolldown’s strengths. Let’s move away from ESBuild’s Node-centric constraints and embrace a bundler that’s fast, flexible, and future-ready.

[marvinhagemeister]

Yeah, we've been keeping an eye on rolldown for quite a while and are in contact with the team behind it. The reason we went with esbuild for now instead is simple: It's been more battle tested. At the time of this writing rolldown is not widely used in production. We built deno bundle in a way that lets us easily swap out the bundler behind it. So once rolldown matures more, it's likely that we'll switch to that.

[nestarz]

@marvinhagemeister By delivering a runtime API, won't that tightly couple the esbuild API with the Deno.bundle API, making the transition harder? Also, the Rolldown roadmap shows rapid progress with a 1.0 beta and will soon become the default in Vite. I suspect that if you are going to stabilize Deno.bundle, it might be wise to wait for that transition—or at least a decision on whether you want to use either of the tools for the foreseeable future.

[marvinhagemeister]

It would be harder if we'd expose the full esbuild API, but that's not what we're doing. Right now we're intentionally only exposing some options which are universal across bundlers. Like there is no plugin support for example in Deno.bundle for this exact reason.

[nestarz]

I understand, thanks @marvinhagemeister, regarding Rolldown's stability, I found a helpful update posted yesterday by its core maintainer that may assist you in planning your strategies: rolldown/rolldown#153 (reply in thread)