Why I Use Bun: Faster Feedback Loops for Daily Work

I started using Bun for one reason: I was spending too much time waiting. Installs, test runs, and dev scripts add up. Bun doesn’t change how you build products — it changes how fast you can iterate on them.

This is not a “Bun vs Node” debate. Node is still the default for a lot of production workloads. For local dev and tooling, Bun has been a big daily win for me.

Where Bun helps me the most

1) Faster installs, less friction

In day-to-day work, I run installs often: switching branches, spiking a feature, running a demo, or fixing a CI issue locally. Bun’s install speed and single-tool approach reduce that overhead.

Typical setup:

bun install
bun dev

2) One tool for scripts: run, test, format

I like having fewer moving parts. In many projects I can replace a chain of tools with a single entry point.

{
  "scripts": {
    "dev": "bun run dev",
    "test": "bun test",
    "typecheck": "bun run typecheck"
  }
}

That makes it easier to onboard and easier to keep scripts consistent across repos.

3) TypeScript-first ergonomics

For small utilities, scripts, or prototypes, Bun makes it easy to write TypeScript without extra ceremony.

Example: a simple script to validate a data file before running a task.

// scripts/validate.ts
import { z } from "zod"
import data from "./data.json"

const Schema = z.array(
  z.object({
    id: z.string(),
    name: z.string().min(1),
  })
)

Schema.parse(data)
console.log("OK")

Run it:

bun run scripts/validate.ts

A small example: a tiny BFF endpoint with Bun

This is the kind of thing I use Bun for when I’m building quick BFF routes or prototypes.

// server.ts
import { serve } from "bun"

serve({
  port: 3000,
  async fetch(req) {
    const url = new URL(req.url)

    if (url.pathname === "/health") {
      return new Response(JSON.stringify({ ok: true }), {
        headers: { "content-type": "application/json" },
      })
    }

    if (url.pathname === "/api/user") {
      // In real code, call upstream here and shape the payload for the UI.
      const user = { id: "123", name: "Ion" }
      return new Response(JSON.stringify(user), {
        headers: { "content-type": "application/json" },
      })
    }

    return new Response("Not found", { status: 404 })
  },
})

console.log("Server running on http://localhost:3000")

Run:

bun server.ts

The key idea: keep client code simple by shaping data at the edge (BFF), and keep iteration fast while you design the API surface.

Where I’m careful

Bun is fast, but I’m still strict about a few things:

Production runtime: if the product is already on Node, I don’t switch runtime casually.

Compatibility: some ecosystems and edge cases still assume Node behaviour.

CI parity: I keep a clear path to run the same checks in CI (and I don’t hide failures behind “works on my machine”).

My rule: Bun is a great accelerator for local dev, scripts, and prototypes. For production, choose it intentionally and validate compatibility early.

The takeaway

Bun helps me shorten feedback loops. That’s the real value.

fewer waits on installs and scripts

easy TypeScript scripting

quick prototypes for BFF routes and tooling

If a tool makes iteration faster without lowering quality, I’ll use it.