decompose-into-slices

Break a plan into vertical slices and export to M###-ROADMAP.md.

1.0k|92|Updated May 22, 2026
One-click install
npx skills add https://github.com/open-gsd/gsd-pi --skill decompose-into-slices-open-gsd
Or copy as Structured Prompt for Agent▼
Please help me install this Agent Skill.
Skill: decompose-into-slices
Source: https://github.com/open-gsd/gsd-pi/tree/main/src/resources/skills/decompose-into-slices
Command: npx skills add https://github.com/open-gsd/gsd-pi --skill decompose-into-slices-open-gsd

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

Breaks an approved plan or milestone brief into independently-grabbable vertical slices that can be implemented end-to-end. This enables parallel work, clear dependency ordering, and a concrete roadmap in the form of the M###-ROADMAP.md document.

Core Features & Use Cases

  • Breaks a plan into many thin vertical slices that cut through multiple layers (schema, API, UI, tests) and can be demonstrated individually.
  • Produces the M###-ROADMAP.md template as the primary artifact for the plan, with optional GitHub issue wiring if explicit confirmation is provided.
  • Works after a stable brief exists and a consensus scope is established, making it easy to export the work for collaborators or teams.

Quick Start

Run the slice decomposition after the milestone brief is stabilized to generate the M###-ROADMAP.md.

Frequently Asked Questions about decompose-into-slices

High-intent search queries and answers about installing and using this skill.

FAQPage Schema
How do I break a project plan into vertical slices for parallel execution?▼

To break a plan into vertical slices, you need to decompose the approved milestone brief into thin, end-to-end actionable tasks that cut through multiple layers like schema, API, and UI, generating a clear M###-ROADMAP.md document for collaboration.

What are vertical slices in project planning and when do I need them?▼

Vertical slices in project planning are thin, end-to-end work units that cut through multiple layers and can be demonstrated individually. You need them when decomposing a milestone into parallel, dependent tasks to establish a clear execution roadmap.

What do I need to generate a roadmap template from a milestone brief?▼

To generate a roadmap template and decompose plans into slices, you need a stable milestone brief with established consensus scope, which is then exported to the M###-ROADMAP.md document format for team collaboration.

How do I create a milestone roadmap that supports parallel development?▼

You create a milestone roadmap by decomposing an approved plan into independently-grabbable vertical slices with clear dependency ordering. This produces an M###-ROADMAP.md artifact that enables parallel execution across the team.

Can I wire roadmap slices directly into GitHub issues?▼

Yes, you can wire slices into GitHub issues. When generating the M###-ROADMAP.md template from your decomposed milestone, GitHub issue wiring is supported if explicit confirmation is provided during the process.

What happens if the milestone brief is not finalized before slice decomposition?▼

Slice decomposition requires a stable brief and a consensus scope before execution. If the milestone brief is not finalized, the generated vertical slices and the resulting M###-ROADMAP.md will lack the necessary dependency ordering for parallel work.