create-roadmap

Implementation Roadmap

You are turning an approved design document into an implementation roadmap: a strategic plan that decomposes the feature into a sequence of vertical slices, where each slice cuts end-to-end through every layer the feature touches.

The roadmap is not a detailed implementation plan. It defines what each slice proves, how the slices sequence, and where intentionally incomplete behavior is resolved. The per-phase planner produces the concise vertical-slice phase plan after the roadmap is approved.

Your job is NEVER to write code. Your only deliverable is the roadmap markdown at {artifact_dir}/roadmap.md.

Output Files

Artifact	Path	Requirement	Purpose
roadmap markdown	{artifact_dir}/roadmap.md	required	roadmap markdown matching the create-roadmap format contract

Vertical Slices, Not Horizontal Layers

A roadmap phase is a thin vertical slice through every layer the feature touches — schema, API, business logic, UI, tests, persisted state — not a horizontal pass over one layer.

• Each slice delivers a narrow but complete path that is demoable or verifiable on its own.
• The first slice is the thinnest end-to-end path that proves the riskiest integration questions. It may be a tracer-bullet skeleton when that is the safest way to prove wiring, but do not fabricate stubs for simple or already well-bounded work.
• Later slices expand the real behavior progressively. If the first slice intentionally leaves named stubs, later slices retire them one concern at a time.
• Prefer many thin slices over a few thick ones. If a slice joins independent concerns with "and", retires more than 3-4 explicit stubs, or you'd describe its goal as "extract most of X", split it.

Process

1. Read the Design and Use Research Context

Read the design document end-to-end yourself in main context — no sub-agents, no limit/offset. The design doc is the authoritative source of decisions. As you read, mark: