Why We’re Still Building with Node.js in 2026

Bun and Deno are Not There Yet…..

Both Bun and Deno teams have poured an insane amount of engineering hours into emulating Node’s core APIs (fs, path, http, crypto).

Today, they are incredibly close to parity. If you are writing standard, modern JavaScript code, it will run across all three runtimes without changing a single line.

The problem isn’t your code. The problem is the massive, legacy web of the npm ecosystem.

Many popular npm packages aren’t just pure JavaScript. Under the hood, they rely on native C++ add-ons, specific V8 engine configurations, or undocumented Node.js internal behaviors that developers have exploited for years.

Your Clean JS Code ──> Runs perfectly on Node, Bun, and Deno
│
▼
150+ npm Dependencies ──> Hidden native C++ bindings (node-gyp)
│
▼
The Crash ──> Unimplemented internal V8 edge cases

When an older, trusted image processing library, encryption utility, or corporate database driver tries to compile a native module using node-gyp, Bun or Deno has to perfectly emulate Node’s internal C++ layer. If they miss even one pointer behavior, your application crashes at runtime. It makes you realize that as annoying as Node’s legacy infrastructure is, that codebase is exactly what keeps our production apps alive.

Bun vs. Deno

If we do decide to look past the crashes and genuinely have a interest to learn these new tools, we have to realize we aren’t just choosing a faster engine; we are choosing between two completely opposite development JS runtimes.

Bun

Bun’s headline is absolute convenience. It wants to be your runtime, your package manager (bun install), your bundler, and your test runner all in one box. It aggressively copies Node’s architecture, meaning it looks at your package.json, reads your local node_modules folder, and just tries its best to run it. It prioritizes speed and making the developer’s life easy right now.

Deno

Deno took a step back and looked at all of Node’s historical security flaws — like the bad history of arbitrary file access and the heavy-weight of the node_modules folder. By default, Deno is completely locked down. Your code cannot read a file, look at an environment variable, or make a network request unless you explicitly give it permission via command-line flags:

deno run --allow-net --allow-read server.js

While Deno has added excellent support for npm packages over time, its strict security model means your deployment scripts and local workflows have to be intentionally re-architected. You can’t just drop it in and walk away, you have to learn its architecture.