Inside Deno: Ryan Dahl’s Vision for the Future of JavaScript Runtime

Introduction

Ryan Dahl is the founder of Node.js and the creator of Deno, a modern JavaScript/TypeScript runtime built with Rust.

The following is a Chinese translation of an interview originally published on Evrone, aimed at sharing Ryan’s thoughts on Deno, the JavaScript ecosystem, and emerging technology trends with Chinese developers.

Interview

Evrone: Your new Deno project has had a big impact on developers. What are you working on now?

Ryan: I spend most of my time on Deno. Although Deno appears as a single executable, it is a large software collection. We continuously improve Deno and are working to use it as infrastructure for commercial projects.

Evrone: You have experience with many languages (C++, Rust, Ruby, JavaScript, TypeScript). Which do you prefer?

Ryan: Lately I enjoy programming in Rust. Its steep learning curve is worth it for my current work; Rust feels like a better C++ and lets me handle low‑level tasks more simply.

JavaScript is never my favorite language, but it is the most common. I don’t see TypeScript as a separate language; it is simply typed JavaScript.

TypeScript lets us build larger, more robust systems on top of JavaScript and is my daily choice. With Deno we aim to eliminate many complexities of transpiling TypeScript to JavaScript.

Evrone: What prevents JavaScript from adding typing support directly?

Ryan: Adding types to JavaScript via TypeScript has been far more successful than similar efforts in Python, PHP, or Ruby. TypeScript is essentially typed JavaScript.

TC39’s cautious design process is exploring a “Types‑As‑Comments” proposal, which could allow JavaScript runtimes to ignore types at runtime. Eventually TypeScript‑like features may become part of the JavaScript standard.

Evrone: As a VIM enthusiast, how do you view modern editors like VS Code?

Ryan: Everyone I work with loves VS Code, and most should use it. I keep VIM for two reasons: I’m fast with it and I appreciate a full‑screen terminal, and because a text‑based tool is lightweight and avoids unnecessary IDE dependencies.

Evrone: Dependency management and security are long‑standing challenges. Do you see Deno as an experimental platform or a best‑practice solution?

Ryan: Deno is practical, not experimental. It builds on years of server‑side JavaScript experience, with deliberate designs for dependency management and security using web‑standard URLs rather than a centralized registry.

Evrone: How do you view online conferences?

Ryan: I have attended some but currently avoid them. I miss the “hallway track” of in‑person events and prefer watching talks at double speed on YouTube.

Evrone: What major dependency‑management challenges do you hope Deno solves?

Ryan: I want Deno to avoid reliance on any centralized dependency repository, similar to how browsers fetch JavaScript.

Evrone: For newcomers, which language should they learn: Python or JavaScript?

Ryan: Both are good for beginners, but overall I consider JavaScript a better entry language because it runs everywhere, is faster, and has a larger community.

Evrone: How do you view async concurrency models like async/await, coroutines, and Go’s goroutines?

Ryan: OS threads don’t scale well for high‑concurrency; Ruby is a poor choice. Goroutines are easy and performant. Node/Deno use non‑blocking I/O and event notifications, but a single instance can’t fully utilize all CPU cores without multiple processes. Go is often a better fit for high‑concurrency services.

Evrone: What is the future of JavaScript/TypeScript in backend, embedded, and ML domains?

Ryan: Dynamic languages excel at rapid development and deployment, which matters more than raw CPU performance. JavaScript remains the fastest dynamic language and may become the dominant one derived from browsers.

We are working to bring Deno into areas like machine learning by adding WebGPU support, enabling TensorFlow.js‑style workloads.

Evrone: How should developers handle TypeScript version updates?

Ryan: TypeScript is stable; using cutting‑edge features can be risky. Prefer stability and compatibility.

Evrone: What education do you recommend for aspiring programmers?

Ryan: Study computer science at university or a related field, spend years learning fundamentals and experimenting.

Evrone: Which third‑party Deno projects do you like?

Aleph.js – A React framework

Opine – Web framework similar to Express

Deno webview – Web‑based GUIs for desktop apps

Puppeteer (as in Node)

Visualize module graphs

ssgo – Minimal flexible static site generator

Evrone: What are Deno’s main technical challenges now?

Ryan: We are building Hyper Web server bindings for HTTP/2, a faster web server, and a Deno Language Server Protocol to improve IDE support. We also aim for broader Web compatibility through extensive platform testing.

Evrone: If you could go back in time, what advice would you give your younger self when starting Node.js?

Ryan: I wasn’t sure async I/O would be easy for newcomers on large projects. I would stress the importance of async I/O, budgeting, communication, and organization for large‑scale software.

Evrone: Advice for developers maintaining npm packages who also want Deno support?

Ryan: Use ESM and watch Deno’s Node compatibility layer (https://deno.land/std/node).