Gate 3: Becoming a Builder

Status: Promotion gate to Builder tier
Required: Complete Layers 07-09
Time estimate: 2-3 weeks (Foundations track) or 1-2 weeks (Accelerated track)

What You've Learned

In Phase 3, you mastered ICN's subsystems:

Identity & Crypto: Practical cryptography, replay protection
Network & Gossip: Eventual consistency, vector clocks
Governance & Contracts: Democratic rule changes, bounded execution

You can now build features, implement new actors/oracles, and design subsystem changes.

Requirements

Complete all three artifacts below. Each demonstrates systems-level understanding.

Artifact 1: Real PR Shipped

What: Ship a meaningful pull request touching multiple crates.

Requirements:

Bug fix, test improvement, or small feature
Touches at least 2 crates (e.g., actor + storage, or API + domain)
Includes tracing spans and metrics
Includes tests proving correctness
Passes CI (fmt, clippy, tests)
Follows commit format and PR conventions

Examples:

Fix a race condition in gossip sync (icn-gossip + tests)
Add new metric to ledger validation (icn-ledger + icn-obs)
Improve error messages in governance (icn-governance + icn-api)

Verification: PR merged or approved by maintainer.

Artifact 2: Peer Review

What: Review another contributor's PR using the boundary-safety rubric.

Requirements:

Choose a PR that touches kernel or app crates
Check for Meaning Firewall violations (kernel importing domain)
Check error handling (no unwrap/expect in protocol paths)
Check observability (tracing spans, metrics)
Check tests (coverage, edge cases)
Leave constructive feedback

Verification: Your review comment demonstrating the rubric checks.

Artifact 3: Teaching Artifact

What: Create one reusable diagram, checklist, or mini-lesson for future contributors.

Options:

Diagram: Actor message flow (e.g., Gossip ↔ Network communication)
Checklist: "Adding a new actor" step-by-step
Mini-lesson: "When to use parking_lot vs tokio::sync locks"
Debugging guide: "How to trace a missing gossip entry"

Requirements:

Practical, specific, actionable
Includes code examples or real file paths
Submitted as markdown in docs/onboarding/resources/ or in a project discussion thread

Verification: Your teaching artifact helps another contributor solve a problem.

After Passing

Congratulations! You are now a Builder.

You can:

✅ Add features and new subsystems
✅ Implement new actors and oracles
✅ Design subsystem changes respecting boundaries
✅ Mentor junior contributors
✅ Review PRs for architectural correctness

Next step: Proceed to Phase 4: Ownership to become a Maintainer.

Submission

Submit your three artifacts to your mentor or in the #onboarding channel:

Link to merged or approved PR
Link to your peer review comment
Your teaching artifact (diagram, checklist, or guide)

Once reviewed and approved, you'll receive the Builder badge and can continue to Phase 4.

Need Help?

Feature unclear? → Ask in #development before starting
Review confused? → CONTRIBUTING.md has review guidelines
Teaching artifact ideas? → Look at docs/onboarding/patterns.md for inspiration

You're now contributing meaningfully — keep going!