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# Contributing to Dynamo

Thank you for your interest in contributing to Dynamo! Whether you're fixing a typo, reporting a bug, improving documentation, or building a new feature—every contribution matters and helps make Dynamo better for everyone.

This guide will help you get started. If you have questions, join us on [Discord](https://discord.gg/nvidia-dynamo) or open a [GitHub Discussion](https://github.com/ai-dynamo/dynamo/discussions).

**TL;DR for experienced contributors:**

1. Fork and clone the repo
2. Create a branch: `git checkout -b yourname/fix-description`
3. Make changes, run `pre-commit`
4. Commit with DCO sign-off: `git commit -s -m "fix: description"`
5. Open a PR targeting `main`

## New to Dynamo?

If this is your first contribution, here's the recommended path:

1. **Set up** your development environment using the [Building from Source](README.md#building-from-source) guide
2. **Find an issue** — Browse [open issues](https://github.com/ai-dynamo/dynamo/issues) or look for:

   | Issue Type | Description |
   |------------|-------------|
   | [Good first issues](https://github.com/ai-dynamo/dynamo/labels/good-first-issue) | Beginner-friendly |
   | [Help wanted](https://github.com/ai-dynamo/dynamo/labels/help-wanted) | Community contributions welcome |

3. **Start small** — Documentation fixes, bug fixes, and test improvements are great first contributions
4. **Ask questions** — Join [Discord](https://discord.gg/nvidia-dynamo) or open a [Discussion](https://github.com/ai-dynamo/dynamo/discussions) if you get stuck

**Community Impact:** 70+ external contributors have merged PRs, with 130+ community contributions since launch and ~8 new contributors joining each month. Your contribution matters—[see our contributors](https://github.com/ai-dynamo/dynamo/graphs/contributors).

## Code of Conduct

We are committed to providing a welcoming and inclusive environment. Please read and follow our [Code of Conduct](CODE_OF_CONDUCT.md).

---

## Ways to Contribute

### Report a Bug

Found something broken? [Open a bug report](https://github.com/ai-dynamo/dynamo/issues/new?template=bug_report.yml) with:
- Steps to reproduce
- Expected vs. actual behavior
- Environment details (OS, GPU, Python version, Dynamo version)

### Improve Documentation

Documentation improvements are always welcome. This includes:
- Fixing typos or unclear explanations
- Adding examples or tutorials
- Improving API documentation

Small doc fixes can be submitted directly as PRs without an issue.

### Propose a Feature

Have an idea for a new feature? [Open a feature request](https://github.com/ai-dynamo/dynamo/issues/new?template=feature_request.yml) to discuss it with Dynamo maintainers before implementation.

### Contribute Code

Ready to write code? See the [Contribution Workflow](#contribution-workflow) section below for the process.

---

## What Happens to Your Issue

### Priority Levels

When triaged, issues are assigned a priority based on impact:

| Priority | Meaning |
|----------|---------|
| **Urgent** | Critical blocker—system failure, security vulnerability, data loss |
| **P0** | High impact—major functionality broken, blocking multiple users |
| **P1** | Medium impact—workarounds exist, or popular feature request |
| **P2** | Low impact—minor bugs, nice-to-have features, cosmetic issues |

### Status Labels

| Status | What It Means |
|--------|---------------|
| `needs-triage` | We're reviewing your issue |
| `needs-info` | We need more details from you |
| `approved-for-pr` | Ready for implementation—submit a PR |
| `in-progress` | Someone is working on this |
| `blocked` | Waiting on external dependency |

### Response Expectations

We aim to:
- **Respond** to new issues within a few business days
- **Triage** high-priority issues (P0/P1) within a week

Issues with no activity for 30 days may be auto-closed (can be reopened).

### Good First Issues

Issues labeled `good-first-issue` are sized for new contributors. We provide extra guidance on these—look for clear acceptance criteria and a suggested approach in the issue description.

---

## Quick Start for Contributors

1. [Fork the repository](https://github.com/ai-dynamo/dynamo/fork) on GitHub
2. Clone your fork and set up your development environment following the [Building from Source](README.md#building-from-source) guide
3. Set up pre-commit hooks: `pip install pre-commit && pre-commit install`

---

## Project Architecture

<!-- We were given the feedback that having information on architecture, languages used, etc. would be helpful for external contributors -->

Understanding Dynamo's architecture helps you find where to make changes. For the complete picture, see the [Architecture Documentation](docs/pages/design-docs/architecture.md) and [Support Matrix](docs/pages/reference/support-matrix.md).

![Dynamo Architecture](docs/assets/img/architecture.png)

### Core Components

| Component | Purpose | Directory |
|-----------|---------|-----------|
| **Frontend** | OpenAI-compatible HTTP API server | `components/src/dynamo/frontend/` |
| **Router** | KV cache-aware request routing with load balancing | `components/src/dynamo/router/` |
| **Planner** | Real-time performance tuning and worker scaling | `components/src/dynamo/planner/` |
| **Workers** | Backend engine integrations (vLLM, SGLang, TensorRT-LLM) | `components/src/dynamo/{vllm,sglang,trtllm}/` |
| **KV Cache Manager** | Multi-tier cache offloading (GPU → CPU → SSD → Object Storage) | `lib/bindings/kvbm/` |
| **SLA Profiler** | Benchmarking and SLA-driven configuration | `components/src/dynamo/profiler/` |

### Communication Planes

| Plane | Purpose | Documentation |
|-------|---------|---------------|
| **Discovery Plane** | Service registration and discovery across components | [docs/pages/design-docs/distributed-runtime.md](docs/pages/design-docs/distributed-runtime.md) |
| **Request Plane** | High-performance request routing between components | [docs/pages/design-docs/request-plane.md](docs/pages/design-docs/request-plane.md) |
| **KV Event Plane** | KV cache event propagation for cache-aware routing | [docs/pages/design-docs/event-plane.md](docs/pages/design-docs/event-plane.md) |

### Kubernetes Deployment

| Component | Purpose | Directory |
|-----------|---------|-----------|
| **Operator** | CRDs, controllers, and webhooks for K8s-native deployment | `deploy/operator/` |
| **Helm Charts** | Templated deployment configurations | `deploy/helm/` |
| **Recipes** | Pre-built deployment configurations for common scenarios | `recipes/` |

### Why These Languages?

| Layer | Language | Why | Directory |
|-------|----------|-----|-----------|
| Core Runtime | Rust | Memory safety, zero-cost abstractions, predictable latency | `lib/runtime/` |
| LLM Engine | Rust | High-throughput token processing, async I/O | `lib/llm/` |
| KV Block Manager | Rust | Direct memory control for GPU/CPU/SSD offloading | `lib/bindings/kvbm/` |
| Backend Integrations | Python | Rapid iteration, framework compatibility | `components/src/dynamo/` |
| Planner & Router | Python | Extensible policies, easy customization | `components/src/dynamo/{planner,router}/` |
| Kubernetes Operator | Go | K8s controller patterns, client-go ecosystem | `deploy/operator/` |

---

## Contribution Workflow

### When Is a GitHub Issue Required?

**Submit a PR directly (no issue needed) if:**
- Your change is **<100 lines of code** AND addresses a simple, focused concern (typos, simple bug fixes, formatting)
- **OR** your PR addresses an **existing approved GitHub Issue** (link with "Fixes #123")

**Create a GitHub Issue first for:**
- Changes ≥100 lines of code
- New features, architecture changes, or multi-component changes
- Any change that requires design discussion

### Issue-First Workflow

For larger contributions, follow these steps:

1. **Create a GitHub Issue** – [Open a Contribution Request](https://github.com/ai-dynamo/dynamo/issues/new?template=contribution_request.yml) using the template.

2. **Describe the Problem** – Explain what you're solving, including context, error messages, or use cases.

3. **Propose a Solution** – Include:
   - **Estimated PR size**: XS / S / M / L / XL / XXL
   - **Files affected**: Approximate number and components
   - **Type of change**: Bug fix, new feature, refactoring, or performance improvement

4. **Get Approval** – Wait for Dynamo maintainers to review and apply the `approved-for-pr` label.

5. **Submit a Pull Request** – [Open a PR](https://github.com/ai-dynamo/dynamo/compare) that references the issue using GitHub keywords (e.g., "Fixes #123").

6. **Address Code Rabbit Review** – Respond to automated Code Rabbit suggestions, including nitpicks.

7. **Trigger CI Tests** – For external contributors, a Dynamo maintainer must comment `/ok to test <commit-id>` to run the full CI suite, where `<commit-id>` is the short SHA of your latest commit. Fix any failing tests before requesting human review.

8. **Request Review** – Add the person who approved your issue as a reviewer. Check [CODEOWNERS](CODEOWNERS) for required approvers based on files modified.

> **Note on AI-Generated Code**: While we encourage using AI tools, you must fully understand every change in your PR. Inability to explain submitted code will result in rejection.

---

## Code Style & Quality

### Pre-commit Hooks

All PRs are checked against [pre-commit hooks](.pre-commit-config.yaml). Run locally:

```bash
pre-commit install
pre-commit run --all-files
```

### Language Conventions

| Language | Style Guide | Formatter |
|----------|-------------|-----------|
| **Python** | [PEP 8](https://peps.python.org/pep-0008/) | `black`, `ruff` |
| **Rust** | [Rust API Guidelines](https://rust-lang.github.io/api-guidelines/) | `cargo fmt`, `cargo clippy` |
| **Go** | [Effective Go](https://go.dev/doc/effective_go) | `gofmt` |

### General Guidelines

- Keep PRs focused—one concern per PR
- Avoid unnecessary complexity
- No commented-out code
- Ensure clean builds (no warnings or errors)
- All tests must pass

### Running GitHub Actions Locally

Use [act](https://nektosact.com/) to run workflows locally:

```bash
act -j pre-merge-rust
```

Or use the [GitHub Local Actions](https://marketplace.visualstudio.com/items?itemName=SanjulaGanepola.github-local-actions) VS Code extension.

---

## DCO & Licensing

### Developer Certificate of Origin

Dynamo requires all contributions to be signed off with the [Developer Certificate of Origin (DCO)](https://developercertificate.org/). This certifies that you have the right to submit your contribution under the project's [Apache 2.0 license](LICENSE).

Each commit must include a sign-off line:

```text
Signed-off-by: Jane Smith <jane.smith@email.com>
```

Add this automatically with the `-s` flag:

```bash
git commit -s -m "fix: your descriptive message"
```

**Requirements:**
- Use your real name (no pseudonyms or anonymous contributions)
- Your `user.name` and `user.email` must be configured in git

⚠️ **DCO Check Failed?** See our [DCO Troubleshooting Guide](DCO.md) for step-by-step instructions to fix it.

### License

By contributing, you agree that your contributions will be licensed under the [Apache 2.0 License](LICENSE).

---

## Getting Help

- **Discord**: [Join our community](https://discord.gg/nvidia-dynamo)
- **Discussions**: [GitHub Discussions](https://github.com/ai-dynamo/dynamo/discussions)
- **Documentation**: [docs.nvidia.com/dynamo](https://docs.nvidia.com/dynamo/)

Thank you for contributing to Dynamo!