Softwr

Software Development · head to head

Bun vs Factory

Bun logo

Bun

Software Development

JavaScript runtime, bundler, test runner and package manager unified in single toolchain

From
Free
Rated
-
Full reviewWebsite
Factory logo

Factory

Software Development

The autonomy stack for enterprise teams

From
$20/month
Rated
-
Full reviewWebsite

The short version

  • Only Bun has a free tier, so it costs nothing to try first.
  • Each has a real cost: Bun linux requires kernel 5.6 or higher (5.1 minimum but with compatibility issues); older systems not supported; Factory business and Enterprise plans require direct sales contact for pricing
  • Prices and features above were last checked on 29 August 2026.

Where they differ

Only the attributes on which Bun and Factory actually diverge.

Attributes where Bun and Factory differ
AttributeBunFactory
Starting priceFree$20/month
Pricing modelopen-sourcesubscription
Free tierYesNo
PlatformsmacOS, Windows, Linux, FreeBSD, AndroidWeb

Identical on both: user rating (Not yet rated), category (Software Development).

What people use each for

The jobs each tool is most often brought in to do.

Bun

  • High-performance JavaScript services prioritising startup time and memory efficiencynot Factory
  • Single-file executable deployment without Node runtime dependenciesnot Factory
  • Monorepo management with workspace supportnot Factory
  • Full-stack development with unified toolchainnot Factory
  • Systems programming and shell scripting with JavaScriptnot Factory

Factory

  • AI agent development and deploymentnot Bun
  • Multi-platform automationnot Bun
  • Background task executionnot Bun
  • Agent orchestrationnot Bun

Where each one falls short

Documented limitations, not opinions. Every one is a constraint you would hit in normal use.

Bun

  • Linux requires kernel 5.6 or higher (5.1 minimum but with compatibility issues); older systems not supported
  • Native Node.js addons not supported directly; requires FFI workarounds for C libraries
  • Ecosystem less mature than Node.js; fewer third-party packages optimised for Bun
  • Windows support newer and less mature than Linux/macOS; occasional edge cases

Factory

  • Business and Enterprise plans require direct sales contact for pricing
  • Individual plans (Pro, Plus, Max) have limited feature details

Pricing, plan by plan

Bun

Free

No published plan breakdown. See the Bun review.

Factory

$20/month
  • Pro$20/month
    • Agent-native multi-platform experience
    • Desktop, CLI, and SDK access
    • Cloud and local background agents
  • Plus$100/month
    • Everything in Pro
    • Approximately 5x usage limits
    • Droid Computers for remote agents
  • Max$200/month
    • Everything in Plus
    • Approximately 10x usage limits
    • Early access to new features
  • Business$null/mo

Which should you pick?

Choose Bun if

  • You want to start without paying.
  • You work on macOS, Windows, Linux, FreeBSD, Android.
Bun review

Choose Factory if

Nothing in the data separates Factory from Bun on the points above - pick on price and on how each one feels to use.

Factory review

Questions people ask

Is Bun or Factory better?
Neither clearly leads. Bun starts at Free and Factory at $20/month, and user ratings are close enough to be indistinguishable. Choose on capability and platform support.
Which is cheaper, Bun or Factory?
Bun has a free tier; the other does not. Paid plans start at Free for Bun and $20/month for Factory.
Does Bun or Factory run on more platforms?
Bun runs on macOS, Windows, Linux, FreeBSD, Android. Factory runs on Web.
Can I use Bun for free?
Yes. Bun has a free tier, so you can try it without paying. Factory starts at $20/month.
What is Bun best used for?
Bun is most often used for high-performance javascript services prioritising startup time and memory efficiency, single-file executable deployment without node runtime dependencies, monorepo management with workspace support, full-stack development with unified toolchain. Of those, high-performance javascript services prioritising startup time and memory efficiency and single-file executable deployment without node runtime dependencies are not what Factory is typically brought in for.

Answered from the vendors’ own pages

Bun: Is Bun free?

Yes, Bun is free and open-source software; no pricing tiers or subscription costs exist for the core runtime and tooling.

Source
Factory: What is Factory.ai's pricing?

Factory.ai offers individual plans starting at USD$20 per month for Pro, USD$100 per month for Plus, and USD$200 per month for Max. Team plans including Business and Enterprise tiers are available at custom pricing based on the number of seats required.

Source
Bun: How much does Bun cost for production use?

Bun itself has no production licensing costs; you only pay for infrastructure (servers, compute) to run applications built with Bun.

Source
Factory: What are the usage limits for each plan?

The Pro plan is the baseline tier. Plus provides approximately 5 times the usage limits of Pro, while Max provides approximately 10 times the usage limits of Pro. Exact usage limits are not specified on the pricing page.

Source
Bun: Does Bun offer commercial support or service tiers?

Bun's free open-source model does not include published commercial support tiers; enterprise support arrangements would require direct contact with Anthropic.

Source
Factory: What AI models are included with Factory.ai?

All Factory.ai plans include access to GPT-5, Claude Opus and Sonnet, Google Gemini, and open-weight models. Business and Enterprise plans also include dedicated compute with partitioned inference and options for on-premise deployment.

Source
Bun: Can I use Bun in production without paying?

Yes, Bun is free to use in production since it is open-source software with no licensing fees, though you must cover your own operational costs.

Source
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