13 stable releases
Uses new Rust 2024
| new 2.1.3 | Jan 21, 2026 |
|---|---|
| 2.1.1 | Jan 20, 2026 |
#121 in Command-line interface
Used in ralph-cli
765KB
16K
SLoC
Ralph Orchestrator
A hat-based multi-agent orchestration framework that keeps AI agents in a loop until the task is done.
"Me fail English? That's unpossible!" - Ralph Wiggum
Alpha Notice: Ralph Orchestrator is under active development. It works today, but expect rough edges and breaking changes between releases.
v1.0.0 was ralphed into existence with little oversight and guidance. v2.0.0 is a simpler, more-structured implementation. Looking for the old version? See v1.2.3.
Table of Contents
- What is Ralph?
- Features
- Installation
- Quick Start
- Configuration
- Presets
- Key Concepts
- CLI Reference
- Architecture
- Building & Testing
- Contributing
- License
- Acknowledgments
What is Ralph?
Ralph implements the Ralph Wiggum technique — autonomous task completion through continuous AI agent iteration. Unlike simple loops, Ralph v2 introduces hat-based orchestration: specialized agent roles that coordinate through events.
"The orchestrator is a thin coordination layer, not a platform. Agents are smart; let them do the work."
The Ralph Tenets
- Fresh Context Is Reliability — Each iteration clears context. Re-read specs, plan, code every cycle.
- Backpressure Over Prescription — Don't prescribe how; create gates that reject bad work.
- The Plan Is Disposable — Regeneration costs one planning loop. Cheap.
- Disk Is State, Git Is Memory — Files are the handoff mechanism.
- Steer With Signals, Not Scripts — Add signs, not scripts.
- Let Ralph Ralph — Sit on the loop, not in it.
See AGENTS.md for the full philosophy.
Features
- Multi-Backend Support — Works with Claude Code, Kiro, Gemini CLI, Codex, and Amp
- Hat System — Specialized agent personas with distinct behaviors
- Event-Driven Coordination — Hats communicate through typed events with glob pattern matching
- Backpressure Enforcement — Gates that reject incomplete work (tests, lint, typecheck)
- Presets Library — 20+ pre-configured workflows for common development patterns
- Interactive TUI — Real-time terminal UI for monitoring agent activity (experimental)
- Session Recording — Record and replay sessions for debugging and testing (experimental)
Installation
Prerequisites
- Rust 1.75+
- At least one AI CLI:
- Claude Code (recommended)
- Kiro
- Gemini CLI
- Codex
- Amp
Via npm (Recommended)
# Install globally
npm install -g @ralph-orchestrator/ralph
# Or run directly with npx
npx @ralph-orchestrator/ralph --version
Via Cargo
cargo install ralph-cli
From Source
git clone https://github.com/mikeyobrien/ralph-orchestrator.git
cd ralph-orchestrator
cargo build --release
# Add to PATH
export PATH="$PATH:$(pwd)/target/release"
# Or create symlink
sudo ln -s $(pwd)/target/release/ralph /usr/local/bin/ralph
Verify Installation
ralph --version
ralph --help
Migrating from v1 (Python)
If you have the old Python-based Ralph v1 installed, uninstall it first to avoid conflicts:
# If installed via pip
pip uninstall ralph-orchestrator
# If installed via pipx
pipx uninstall ralph-orchestrator
# If installed via uv
uv tool uninstall ralph-orchestrator
# Verify removal
which ralph # Should return nothing or point to new Rust version
The v1 Python version is no longer maintained. See v1.2.3 for historical reference.
Quick Start
1. Initialize a Project
# Minimal config for Claude (recommended)
ralph init --backend claude
# Use a preset workflow
ralph init --preset tdd-red-green
# Combine preset with different backend
ralph init --preset spec-driven --backend kiro
# See all available presets
ralph init --list-presets
This creates ralph.yml in your current directory.
2. Define Your Task
Option A: Create a PROMPT.md file:
cat > PROMPT.md << 'EOF'
Build a REST API with the following endpoints:
- POST /users - Create a new user
- GET /users/:id - Get user by ID
- PUT /users/:id - Update user
- DELETE /users/:id - Delete user
Use Express.js with TypeScript. Include input validation
and proper error handling.
EOF
Option B: Pass inline prompt when running:
ralph run -p "Add input validation to the user API endpoints"
3. Run Ralph
# Autonomous mode (headless, default)
ralph run
# With inline prompt
ralph run -p "Implement the login endpoint with JWT authentication"
# Interactive TUI mode (experimental)
ralph run -i
# Resume interrupted session
ralph resume
# Dry run (show what would execute)
ralph run --dry-run
Configuration
Ralph uses a YAML configuration file (ralph.yml by default).
Minimal Configuration
# ralph.yml
cli:
backend: "claude"
event_loop:
completion_promise: "LOOP_COMPLETE"
max_iterations: 100
Full Configuration Reference
# Event loop settings
event_loop:
completion_promise: "LOOP_COMPLETE" # Output that signals completion
max_iterations: 100 # Maximum orchestration loops
max_runtime_seconds: 14400 # 4 hours max runtime
idle_timeout_secs: 1800 # 30 min idle timeout
starting_event: "task.start" # First event published
# CLI backend settings
cli:
backend: "claude" # claude, kiro, gemini, codex, amp, custom
prompt_mode: "arg" # arg (CLI argument) or stdin
experimental_tui: false # Enable TUI mode support
# Core behaviors (always injected into prompts)
core:
scratchpad: ".agent/scratchpad.md" # Shared memory across iterations
specs_dir: "./specs/" # Directory for specifications
guardrails: # Rules injected into every prompt
- "Fresh context each iteration - scratchpad is memory"
- "Don't assume 'not implemented' - search first"
- "Backpressure is law - tests/typecheck/lint must pass"
# Custom hats (omit to use default planner/builder)
hats:
my_hat:
name: "My Hat Name" # Display name
triggers: ["some.event"] # Events that activate this hat
publishes: ["other.event"] # Events this hat can emit
instructions: | # Prompt instructions
What this hat should do...
Presets
Presets are pre-configured workflows for common development patterns.
Development Workflows
| Preset | Pattern | Description |
|---|---|---|
feature |
Planner-Builder | Standard feature development |
feature-minimal |
Single hat | Minimal feature development |
tdd-red-green |
Test-Implement-Refactor | TDD with red-green-refactor cycle |
spec-driven |
Spec-Build-Verify | Specification-first development |
refactor |
Analyze-Plan-Execute | Code refactoring workflow |
Debugging & Investigation
| Preset | Pattern | Description |
|---|---|---|
debug |
Investigate-Fix-Verify | Bug investigation and fixing |
incident-response |
Triage-Fix-Postmortem | Production incident handling |
code-archaeology |
Explore-Document-Present | Legacy code understanding |
Review & Quality
| Preset | Pattern | Description |
|---|---|---|
review |
Analyze-Critique-Suggest | Code review workflow |
pr-review |
Multi-Perspective | PR review with specialized reviewers |
adversarial-review |
Critic-Defender | Devil's advocate review style |
Documentation
| Preset | Pattern | Description |
|---|---|---|
docs |
Write-Review-Publish | Documentation writing |
documentation-first |
Doc-Implement-Sync | Doc-first development |
Specialized
| Preset | Pattern | Description |
|---|---|---|
api-design |
Design-Implement-Document | API-first development |
migration-safety |
Analyze-Migrate-Verify | Safe code migrations |
performance-optimization |
Profile-Optimize-Benchmark | Performance tuning |
scientific-method |
Hypothesis-Experiment-Conclude | Experimental approach |
mob-programming |
Rotate roles | Simulated mob programming |
socratic-learning |
Question-Answer-Synthesize | Learning through dialogue |
research |
Gather-Analyze-Synthesize | Research and analysis |
gap-analysis |
Current-Target-Plan | Gap identification |
Using Presets
# List all available presets
ralph init --list-presets
# Initialize with a preset
ralph init --preset tdd-red-green
# Use preset with different backend
ralph init --preset spec-driven --backend gemini
# Override existing config
ralph init --preset debug --force
Key Concepts
Hats
Hats are specialized agent personas. Each hat has:
- Triggers: Events that activate this hat
- Publishes: Events this hat can emit
- Instructions: Prompt injected when hat is active
View event history:
ralph events
Scratchpad
All hats share .agent/scratchpad.md — persistent memory across iterations. This enables hats to build on previous work rather than starting fresh.
The scratchpad is the primary mechanism for:
- Task tracking (with
[ ],[x],[~]markers) - Context preservation between iterations
- Handoff between hats
Backpressure
Ralph enforces quality gates through backpressure. When a builder publishes build.done, it must include evidence:
tests: pass, lint: pass, typecheck: pass
CLI Reference
Commands
| Command | Description |
|---|---|
ralph run |
Run the orchestration loop (default) |
ralph resume |
Resume from existing scratchpad |
ralph events |
View event history |
ralph init |
Initialize configuration file |
ralph clean |
Clean up .agent/ directory |
ralph emit |
Emit an event to the event log |
Global Options
| Option | Description |
|---|---|
-c, --config <FILE> |
Config file path (default: ralph.yml) |
-v, --verbose |
Verbose output |
--color <MODE> |
Color output: auto, always, never |
ralph run Options
| Option | Description |
|---|---|
-p, --prompt <TEXT> |
Inline prompt text |
-P, --prompt-file <FILE> |
Prompt file path |
--max-iterations <N> |
Override max iterations |
--completion-promise <TEXT> |
Override completion trigger |
--dry-run |
Show what would execute |
-i, --interactive |
Enable TUI mode (experimental) |
-a, --autonomous |
Force headless mode |
--idle-timeout <SECS> |
TUI idle timeout (default: 30) |
--record-session <FILE> |
Record session to JSONL |
-q, --quiet |
Suppress output (for CI) |
ralph init Options
| Option | Description |
|---|---|
--backend <NAME> |
Backend: claude, kiro, gemini, codex, amp |
--preset <NAME> |
Use preset configuration |
--list-presets |
List available presets |
--force |
Overwrite existing config |
Architecture
Ralph is organized as a Cargo workspace with six crates:
| Crate | Purpose |
|---|---|
ralph-proto |
Protocol types: Event, Hat, Topic, Error |
ralph-core |
Business logic: EventLoop, HatRegistry, Config |
ralph-adapters |
CLI backend integrations (Claude, Kiro, Gemini, etc.) |
ralph-tui |
Terminal UI with ratatui |
ralph-cli |
Binary entry point and CLI parsing |
ralph-bench |
Benchmarking harness (dev-only) |
Building & Testing
Build
cargo build # Debug build
cargo build --release # Release build
Test
# Run all tests (includes smoke tests with JSONL replay)
cargo test
# Run smoke tests specifically
cargo test -p ralph-core smoke_runner
# Run Kiro-specific smoke tests
cargo test -p ralph-core kiro
Smoke Tests
Smoke tests use recorded JSONL fixtures instead of live API calls — fast, free, and deterministic.
Fixture locations:
crates/ralph-core/tests/fixtures/basic_session.jsonl— Claude CLI sessioncrates/ralph-core/tests/fixtures/kiro/— Kiro CLI sessions
Recording new fixtures:
# Record a session
ralph run -c ralph.yml --record-session session.jsonl -p "your prompt"
# Or capture raw CLI output
claude -p "your prompt" 2>&1 | tee output.txt
Linting
cargo clippy --all-targets --all-features
cargo fmt --check
Contributing
Contributions are welcome! Please:
- Fork the repository
- Create a feature branch (
git checkout -b feature/amazing-feature) - Write tests for new functionality
- Ensure
cargo testpasses - Run
cargo clippyandcargo fmt - Commit your changes (
git commit -m 'Add amazing feature') - Push to the branch (
git push origin feature/amazing-feature) - Open a Pull Request
See AGENTS.md for development philosophy and conventions.
License
MIT License — See LICENSE for details.
Acknowledgments
- Geoffrey Huntley — Creator of the Ralph Wiggum technique
- Harper Reed — Spec-driven development methodology
- Strands Agent SOPs — Natural language workflows that enable AI agents to perform complex, multi-step tasks with consistency and reliability.
- ratatui — Terminal UI framework
- portable-pty — Cross-platform PTY support
"I'm learnding!" - Ralph Wiggum
Dependencies
~24–42MB
~569K SLoC