Greenfield Demo Flow

Step-by-step tutorial for generating a spec package, building with an external agent, and closing Omar loop to green.

  • tutorial
  • greenfield
  • demo
  • omar-loop
  • builder-studio

Use this tutorial to run a complete greenfield demonstration from idea to clean PR.

Suggested demo app (fast but realistic)

Build a "Neon Orbit Arena" prototype:

  • frontend: React + Three.js HUD + WebSocket event feed
  • backend: Node.js + TypeScript API for match state
  • scoring service: dedicated component exposed through a private service API
  • risk profile: auth/session handling, unsafe input parsing, race-prone realtime updates

Step 1: Generate the build package

  1. open Prompt Builder
  2. describe the project outcome
  3. generate and export:
  • spec sheet
  • builder prompt
  • Omar gate workflow
  • build playbook

Step 2: Prepare repository

  1. create GitHub repo
  2. protect `main` with required Omar checks
  3. add `SENTINELAYER_TOKEN` as a GitHub Actions secret
  4. commit the generated package files to repo root
  5. connect the repo in Builder Studio so file context chips can be attached from the file tree

Step 3: Execute in coding agent

  1. open repo in Codex CLI / Claude Code / Cursor / Copilot / Augment / Replit
  2. attach package artifacts as context
  3. request phased implementation with Omar loop enforcement
  4. keep writes on feature branch only
  5. use context chips for high-priority files before each prompt (auth, CI, runtime config)

Prompt starter (copy/edit)

```text

Use spec_sheet.md and builder_prompt.md as hard constraints.

Implement phase by phase on a feature branch.

After each phase: run lint, typecheck, tests, build; open/update PR; wait for Omar; fix all P0-P2; repeat until clean.

Log decisions and evidence in .sentinel/.

```

Step 4: Run deterministic Omar loop

  1. scan
  2. patch
  3. test
  4. rescan
  5. stop only when `P0-P2` are clean and gates are green

Step 5: Present evidence

  • show runtime timeline and terminal excerpts
  • show stop reason and gate summary
  • export evidence bundle
  • show Runtime Insights compare/baseline KPI snapshot
  • show PR history proving P0-P2 closure loop

This flow is suitable for customer demos, partner diligence, and internal launch reviews.

Structured Answers

Can I run this tutorial without exposing private architecture details?

Yes. The tutorial uses product-visible artifacts, gate outcomes, and KPI evidence only.

What is the pass condition for the demo?

A clean PR with Omar gate green, no unresolved P0-P2 findings, and an exported evidence bundle.