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book-ddia-data-design skillA

book-ddia-data-design is agent-read markdown (skill) from kunolu/640-skills: Guides data-intensive design checks for consistency, reliability, schema evolution, and data flow risks. In strict tasks, mandatory before design stabilizes or implementation begins when changing persisted/shared data, schemas, migrations, shared/persistent/cross-request/cross-process caches, async or cross-service flows, data ownership, or recovery; in default/lite tasks, use on demand when those risks or explicit delivery requirements are present..

Indexed from public GitHub and served as immutable, content-addressed versions. Install it pinned to an exact SHA-256 with the mdr CLI, and every file is verified against the hash recorded here before it reaches your agent. The deterministic audit below grades the latest version, and the same file always earns the same grade.

What the file says

# Book DDIA Data Design

Use this Skill when a change can fail because of data semantics, distributed behavior, or operational reality rather than ordinary code structure.

It is derived from the `mini` rule style of `agent-rules-books` and should complement project architecture, task design, source/LSP/contract impact analysis, tests, and production validation.

## Strict Development Gate

In a strict task, run this Skill before design artifacts become stable or implementation begins when the task changes any of the following:

- Persisted or shared data, databases, schemas, or migrations.
- shared, persistent, cross-request, or cross-process caches; queues, events, streams, jobs, ETL, or analytics pipelines.
- Cross-service data flow or API ownership.
- Data ownership, source of truth, transaction boundaries, or read / write paths.
- Backfill, replay, rollback, or recovery behavior.

Emit a separate visible review:

```text
DDIA Data Design Review
Status: confirmed | needs-design-change | blocked
Data owner and source of truth: ...
Write / read / async / failure paths: ...
Consistency model: ...
Idempotency / ordering / retry / deduplication: ...
…

Read the whole file at its exact version.

How to install

Latest version
mdr add kunolu/640-skills/book-ddia-data-design@git:20260920.f9bbb90
Exact content
mdr add kunolu/640-skills/book-ddia-data-design@sha256:c5ef7682ef80bb65

Pin to a label to follow the author's releases, or to a sha256 to freeze the exact bytes forever. Either way the resolved hash is written to mdr.lock, and mdr install reproduces it on any machine.

Badge

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Versions

versioncommittedcommitsizeaudit
git:20260920.f9bbb90 latest2026-09-20 f9bbb90 4,270 BA view · diff
git:20260719.63495402026-07-19 6349540 4,063 BA view · diff
git:20260718.951ea5b2026-07-18 951ea5b 2,152 BA view

Audit of the latest version

A  17 of 17 checks passed. Deterministic, no model, same answer every run.
  • pass: Frontmatter block present
  • pass: Frontmatter declares a name
  • pass: Frontmatter declares a description
  • pass: Size between 200 bytes and 200 KB (4270 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

GitHub

kunolu/640-skills · 113 stars · license Apache-2.0 · pushed 2026-09-25 · branch main

API

GET https://markdownregistry.com/api/v1/artifacts/art_t2mf7xx75cdw53ss
GET https://markdownregistry.com/api/v1/resolve?ref=kunolu/640-skills/book-ddia-data-design
GET https://markdownregistry.com/api/v1/blob/c5ef7682ef80bb65fa06e64cb428d14642c4fd9a24f0fc247544724197e85ca6

Your agent 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.

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