vertical-slice SKILL.md skillA
vertical-slice from etr/groundwork is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add etr/groundwork/vertical-slice@git:20260622.3609064Pins git:20260622.3609064 in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- etr/groundwork
- Path
skills/vertical-slice/SKILL.md- Versions recorded
- 1
- Latest version
- git:20260622.3609064, committed Jun 22, 2026
- Size
- 4,614 bytes
- Repository stars
- 45
- License
- MIT
Use when building a feature large enough to span multiple layers - structure the work as thin, end-to-end, independently-shippable slices behind a feature flag instead of building layer-by-layer.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
# Vertical Slice
## Overview
Build a feature as a sequence of **thin vertical slices**. Each slice cuts through the full stack — UI → logic → data — and delivers exactly one observable behavior, kept behind a feature flag until it is complete and tested.
**Core principle:** thin vertical slice (defined in `${CLAUDE_PLUGIN_ROOT}/references/engineering-principles.md`). The opposite is horizontal building — finishing the whole data layer, then the whole logic layer, then the whole UI. Horizontal work integrates *last*, which means every integration risk surfaces at the end, all at once, when there is no budget left to absorb it. Vertical slices integrate *first* and *continuously*: each slice proves the stack connects before you build the next one.
A slice is the unit of progress. Finish one — flagged, end-to-end, tested, committed — before starting the next. Cutting a feature into sliced tasks happens during planning ([[create-tasks]]); this skill governs *building* each slice. See [[work-on]] for driving the work item end-to-end and [[test-driven-development]] for the inner loop of each slice.
## When to Use
…Read the whole file at its exact version.
How to install
mdr add etr/groundwork/vertical-slice@sha256:24ec0e5836d9645bThe line at the top of this page pins the label git:20260622.3609064, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_ueobruuoh4ymee4f)
4 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 1 version of this file, committed on Jun 22, 2026.
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (4614 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
etr/groundwork · 45 stars · license MIT · pushed 2026-10-30 · branch main
API
GET https://markdownregistry.com/api/v1/artifacts/art_ueobruuoh4ymee4f GET https://markdownregistry.com/api/v1/resolve?ref=etr/groundwork/vertical-slice GET https://markdownregistry.com/api/v1/blob/24ec0e5836d9645b565d2a1499c42812a03afc9094992d9b721caff5c9732ccf
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.