Automated summary
Translate domain rules into code structures using entities, value objects, aggregates, and domain events with explicit invariants.
Strengths
- Derives aggregate boundaries from invariants rather than from database tables
- Encourages immutable value objects and behavior-rich domain objects instead of anemic models
- Keeps repository contracts at aggregate root boundaries
- Includes a concrete TypeScript example and a tactical checklist reference
Limitations
- Does not cover strategic design or deployment architecture
- Does not address persistence, database choices, or transport protocols
- Invariant test coverage is left to the team since testing patterns are only referenced
Use it when you need to turn domain rules into code structures with explicit invariants and domain event boundaries.
Avoid it while strategic boundaries are still undefined or when full DDD complexity is not justified.
Security analysis
SafeThe skill is purely instructional DDD guidance. It declares no tools and contains no code execution, network access, secret handling, obfuscation, or destructive instructions; the example is harmless illustrative TypeScript.
No concerns found
How this analysis is madeExamples
Model an Order aggregate in TypeScript where an order cannot be submitted empty or submitted twice, and emit a domain event on submission.Refactor this anemic service with public setters into domain objects using value objects and aggregate invariants.Design repository contracts at aggregate root boundaries for this invoicing domain and list the domain events for each state transition.name: ddd-tactical-patterns description: "Apply DDD tactical patterns in code using entities, value objects, aggregates, repositories, and domain events with explicit invariants." risk: safe source: self tags: "[ddd, tactical, aggregates, value-objects, domain-events]" date_added: "2026-02-27"
DDD Tactical Patterns
Use this skill when
- Translating domain rules into code structures.
- Designing aggregate boundaries and invariants.
- Refactoring an anemic model into behavior-rich domain objects.
- Defining repository contracts and domain event boundaries.
Do not use this skill when
- You are still defining strategic boundaries.
- The task is only API documentation or UI layout.
- Full DDD complexity is not justified.
Instructions
- Identify invariants first and design aggregates around them.
- Model immutable value objects for validated concepts.
- Keep domain behavior in domain objects, not controllers.
- Emit domain events for meaningful state transitions.
- Keep repositories at aggregate root boundaries.
If detailed checklists are needed, open references/tactical-checklist.md.
Example
class Order {
private status: "draft" | "submitted" = "draft";
submit(itemsCount: number): void {
if (itemsCount === 0) throw new Error("Order cannot be submitted empty");
if (this.status !== "draft") throw new Error("Order already submitted");
this.status = "submitted";
}
}
Limitations
- This skill does not define deployment architecture.
- It does not choose databases or transport protocols.
- It should be paired with testing patterns for invariant coverage.
From the file to a first result
The download contains exactly the content displayed on this page. This copy may differ from the latest version in the source repository.
View the source and supporting filesThis download contains SKILL.md only. Any scripts, references, templates and dependencies are not included. Get the required files from the source, preserving their directory structure, before continuing.
1. Download the file
Download SKILL.mdFrom the root of a test project, save the file as .skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md, or use the command below. This folder is for inspecting the skill before installation.
Command for macOS/Linux or WSL: requires a POSIX shell and curl. On Windows without WSL, use the download button and create the folder manually.
mkdir -p '.skill-downloads/ddd-tactical-patterns-ms2s7cqo' && curl --fail --show-error --location 'https://skills-guides.com/api/skills/ddd-tactical-patterns-ms2s7cqo/download' --output '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md.part' && mv '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md.part' '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md'2. Check prerequisites
Read SKILL.md before using it. If it references scripts or external services, inspect them and prepare the required access in your test environment.
No recognized prerequisites section in this file. This does not mean it is self-contained: libraries, tools and access requirements may be mentioned elsewhere in the content or source repository.
The platforms on this page are catalog indications. The paths below follow tool documentation; they do not prove this skill has been run in those tools. No minimum tool version is confirmed for this listing.
3. Load the skill
After inspection, copy the complete folder into your project using one of the commands below, then open a new tool session. The command stops if a folder with the same name already exists: compare the files before replacing it.
Claude Code
test -f '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && test -s '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && mkdir -p '.claude/skills' && test ! -e '.claude/skills/ddd-tactical-patterns' && cp -R '.skill-downloads/ddd-tactical-patterns-ms2s7cqo' '.claude/skills/ddd-tactical-patterns'Cursor
test -f '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && test -s '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && mkdir -p '.cursor/skills' && test ! -e '.cursor/skills/ddd-tactical-patterns' && cp -R '.skill-downloads/ddd-tactical-patterns-ms2s7cqo' '.cursor/skills/ddd-tactical-patterns'Codex
test -f '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && test -s '.skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md' && mkdir -p '.agents/skills' && test ! -e '.agents/skills/ddd-tactical-patterns' && cp -R '.skill-downloads/ddd-tactical-patterns-ms2s7cqo' '.agents/skills/ddd-tactical-patterns'OpenSkills
OpenSkills must already be installed. The local install/read procedure is checked with OpenSkills 1.5.0, which requires Node.js ≥ 20.6.0. Catalog slugs are not resolved automatically.
Official OpenSkills installationopenskills install './.skill-downloads/ddd-tactical-patterns-ms2s7cqo'openskills read 'ddd-tactical-patterns-ms2s7cqo'Reading should display the installed file content and its base directory. It does not run the skill or install its dependencies.
For an agent that reads AGENTS.md, then sync the index. This command changes AGENTS.md: review the diff before using it.
openskills syncManual method or another tool: attach SKILL.md to a conversation, or open it in an agent that can read files. Include any required supporting resources. No universal folder is recognized by every tool.
4. Try a first task
Use a short, synthetic input: an API endpoint, a small document or an interface brief. In a new conversation, attach the file or give the agent its path, then adapt this request:
Read .skill-downloads/ddd-tactical-patterns-ms2s7cqo/SKILL.md and apply its instructions to this example: [describe a test input]. Identify any missing files, dependencies or access. Produce the result requested by the skill without inventing data or running unreviewed scripts.Expected result: output matching the skill instructions, or a precise list of missing prerequisites. A read confirmation alone does not validate a first use. If an external resource is unavailable, that path remains untested.
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