Jan 04, 2026
Comparison
8 min read
Bun vs Node.js vs Deno
A deep comparison of the three major JavaScript runtimes: performance, security, and developer experience.
Node.js
STABILITY
Deno
SECURITY
Bun
SPEED
JavaScript is no longer tied to a single runtime. Today, developers actively choose between Node.js, Deno, and Bun. Each represents a different philosophy of how JavaScript should run outside the browser.
Runtime Philosophies
| Runtime | Core Philosophy |
|---|---|
| Node.js | Stability & ecosystem dominance |
| Deno | Security-first & standards |
| Bun | Performance-first & all-in-one |
Key Insight
There is no single “best” runtime — only the best runtime for your use case.
Node.js — The Backbone of the Web
Node.js remains the most widely used JavaScript runtime in production.
Strengths
- Massive npm ecosystem
- Enterprise-grade stability
- Long-term support guarantees
Tradeoffs
- Slower cold starts
- Tooling fragmentation
- Legacy APIs
When to Use Node.js
Choose Node.js when stability, ecosystem size, and long-term maintenance matter more than raw speed.
Deno — Secure by Design
Deno fixes many of Node.js’s early design compromises.
Strengths
- Explicit permission model
- Native TypeScript
- Web-standards-first APIs
Tradeoffs
- Smaller ecosystem
- Permissions add friction
- Slower installs than Bun
Security First
Deno is ideal when sandboxing, isolation, and least-privilege execution are non-negotiable.
Bun — Performance as a Feature
Bun reimagines JavaScript tooling as a single, cohesive system.
Strengths
- Fastest startup times
- Built-in package manager, bundler, test runner
- Minimal configuration
Tradeoffs
- Partial Node API compatibility
- Young ecosystem
- Rapidly evolving
Why Bun Feels Different
Bun optimizes for developer flow — fewer tools, fewer configs, faster iteration.
Performance Comparison
| Feature | Node.js | Deno | Bun |
|---|---|---|---|
| Cold Start | Slow | Medium | Fastest |
| Package Install | Slow | Medium | Instant |
| Built-in Tooling | No | Partial | Yes |
Which One Should You Choose?
Choose Node.js if:
- • You need ecosystem maturity
- • You maintain large production systems
Choose Deno if:
- • Security is your top priority
- • You’re building edge/sandboxed apps
Choose Bun if:
- • You want speed and simplicity
- • You’re building modern apps
Final Thoughts
Node.js laid the foundation.
Deno corrected the mistakes.
Bun redefined expectations.
JavaScript runtimes are evolving — fast.
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