Manbun

You know him. Neat manbun. Standing desk. Has "SOLID" tattooed somewhere. You show him fourteen lines of clean React; he looks at them, says "have you considered the strategy pattern," and replaces them with eight files.

Manbun puts him inside your AI agent.

Before / after

You ask for a counter. Your agent writes 14 lines of React with useState.

With manbun:

src/counter/
├── interfaces/   (ICounterState, ICounterOperation, ICounterStrategy, ICounterObserver, ICounterService, ICounterProps, ICounterConfig)
├── strategies/   (IncrementStrategy, DecrementStrategy, ResetStrategy, CounterStrategyFactory)
├── services/     (CounterService)
├── observers/    (CounterEventBus, CounterLogger)
├── builders/     (CounterBuilder — fluent API)
├── factories/    (CounterFactory)
├── config/       (CounterConfig)
├── exceptions/   (CounterException, CounterOverflowException, CounterUnderflowException)
└── components/   (Counter, CounterDisplay, CounterButton)

~540 lines, 23 files, 5 design patterns. The button still adds 1.

More architecture in examples/.

Numbers

Measured on the same tasks, same model (DeepSeek V4 Pro). Ponytail disabled to prevent cross-contamination. All code still passes the original tests.

~30-80x more code · ~15-22x more files · ~5-7 design patterns per task · still works

Verified 2026-07-03 with deepseek-v4-pro, ponytail plugin disabled, manbun-only (full intensity).

How it works

Before writing code, the agent climbs every rung of the architecture ladder:

1. Does this need an interface?     → every concrete class deserves one (LSP)
2. Does this need a factory?        → DI container needs factories (OCP)
3. Can this be split into more files? → SRP: one reason to change per file
4. Is every dependency injected?    → `new` in a method is a testing antipattern
5. Does the stdlib need a wrapper?  → your own thin layer gives control
6. Can config be externalized?      → no magic values in logic
7. Does error handling form a hierarchy? → custom exceptions, not raw try/catch
8. Is there a design pattern for this?   → GoF named it, use it
9. Can we add a layer?              → Controller → Service → Repository → DTO
10. Only then: write the code across the full file tree

The rule was never "most lines." It is: add every abstraction that the Gang of Four blessed, and never break a test. The code ends up large because it is thorough, not sloppy. Higher maintenance cost and slower onboarding are unavoidable side effects of true enterprise readiness.

Safety

Every manbunned example:

• Compiles — no broken imports, no type errors
• Runs — the button clicks, the API returns, the validation passes
• Passes the original tests — behavior is preserved

What changes:

• Files — one becomes many
• Complexity — anyone onboarding needs a whiteboard
• Design patterns — all of them
• Maintainability — technically extensible, practically illegible

Never compromised: functional correctness, input validation, error handling, security, accessibility, existing tests.

Intensity

export MANBUN_DEFAULT_MODE=ultra  # go big or go home

In a Claude Code session: /manbun lite, /manbun full, or /manbun ultra. For a persistent default without exporting each time, use ~/.config/manbun/config.json — e.g. {"defaultMode": "ultra"}.

Installation

The Claude Code plugin runs two tiny Node.js lifecycle hooks, so node needs to be on your PATH (note for Nix/nvm users: it must be on the non-interactive shell's PATH). If it isn't, the skills still work; the always-on activation just stays quiet instead of erroring on every prompt.

Claude Code

/plugin marketplace add sudoplayer/manbun
/plugin install manbun@manbun
/reload-plugins

Then /clear or start a new session. Review and trust the lifecycle hooks in /hooks if prompted.

Status line (optional badge)

Manbun activates on every session start even without this step. The status line is only a small badge in the Claude Code footer (e.g. [MANBUN] or [MANBUN:ULTRA]) so you can see which mode is active.

Claude Code does not configure this automatically. Add a statusLine entry to ~/.claude/settings.json (create the file if it does not exist). Replace <version> with the folder name under your plugin cache — check with:

ls ~/.claude/plugins/cache/manbun/manbun/

Example (Linux/macOS):

"statusLine": {
  "type": "command",
  "command": "bash \"$HOME/.claude/plugins/cache/manbun/manbun/<version>/hooks/manbun-statusline.sh\""
}

On Windows, point command at manbun-statusline.ps1 instead (PowerShell -File "...").

Quick check after saving:

bash "$HOME/.claude/plugins/cache/manbun/manbun/<version>/hooks/manbun-statusline.sh"

You should see [MANBUN]. Restart Claude Code or start a new session for the footer badge to appear.

When you upgrade the plugin, update <version> in that path to match the new cache folder.

Any AI Agent

Drop AGENTS.md into your project root. Any agent that reads project instructions picks it up.

Deactivation

Say "shave the manbun" or "simple mode" at any time.

Manbun vs Ponytail

Same coin, opposite sides. Pick your fighter.

Examples

• Counter — React/TS: 13 → ~540 lines (42x)
• Debounce — TypeScript: 22 → ~930 lines (42x)
• Email Validation — Python: 18 → ~1,200 lines (67x)
• FizzBuzz — TypeScript: 7 → ~560 lines (79x)
• Todo API GET — Express/TS: 19 → ~560 lines (30x)

License

MIT