Automated summary
A guide to designing and implementing event stores for event-sourced systems, with patterns for PostgreSQL, EventStoreDB and DynamoDB.
Strengths
- Covers architecture, requirements and technology selection before implementation
- Ships concrete templates: a PostgreSQL schema, a Python implementation, EventStoreDB usage and a DynamoDB store
- Includes explicit do's and don'ts checklists
- Modular sub-skill layout lets you load only the part you need
Limitations
- The main file is essentially an index; schemas, code samples and details live in the sub-skills and playbook
- Event versioning and schema migration are not covered in depth in the main file
- Assumes prior familiarity with event sourcing concepts such as aggregates and optimistic concurrency
Reach for it when designing an event store, comparing event persistence technologies, or defining a storage schema for an event-sourced system.
Skip it for conventional CRUD applications without event sourcing, or for tasks unrelated to event persistence and design.
Security analysis
SafeThe skill is a documentation/guidance skill with no declared tools and no executable instructions. It only references sub-skill files for event store design guidance. There is no risk of destructive actions, exfiltration, or unsafe tool usage.
No concerns found
How this analysis is madeExamples
Design a PostgreSQL schema for the event store of an event-sourced orders system. It must support optimistic concurrency per stream and a stable global ordering. Show the tables, indexes, and how an append is done atomically in one transaction.I'm building an event-sourced system with roughly 5k appends per second and multi-region read replicas. Compare EventStoreDB and DynamoDB as the event store and recommend one, with the tradeoffs spelled out.Implement a minimal Python event store with append-to-stream, load-stream and a simple subscription mechanism, following the patterns and pitfalls from this skill.version: 4.1.0-fractal name: event-store-design description: Design and implement event stores for event-sourced systems. Use when building event sourcing infrastructure, choosing event store technologies, or implementing event persistence patterns.
Event Store Design
Comprehensive guide to designing event stores for event-sourced applications.
Do not use this skill when
- The task is unrelated to event store design
- You need a different domain or tool outside this scope
Instructions
- Clarify goals, constraints, and required inputs.
- Apply relevant best practices and validate outcomes.
- Provide actionable steps and verification.
- If detailed examples are required, open
resources/implementation-playbook.md.
Use this skill when
- Designing event sourcing infrastructure
- Choosing between event store technologies
- Implementing custom event stores
- Optimizing event storage and retrieval
- Setting up event store schemas
- Planning for event store scaling
Core Concepts
🧠 Knowledge Modules (Fractal Skills)
1. 1. Event Store Architecture
2. 2. Event Store Requirements
3. Template 1: PostgreSQL Event Store Schema
4. Template 2: Python Event Store Implementation
5. Template 3: EventStoreDB Usage
6. Template 4: DynamoDB Event Store
7. Do's
8. Don'ts
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/event-store-design-mrwakcrw/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/event-store-design-mrwakcrw' && curl --fail --show-error --location 'https://skills-guides.com/api/skills/event-store-design-mrwakcrw/download' --output '.skill-downloads/event-store-design-mrwakcrw/SKILL.md.part' && mv '.skill-downloads/event-store-design-mrwakcrw/SKILL.md.part' '.skill-downloads/event-store-design-mrwakcrw/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.
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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/event-store-design-mrwakcrw/SKILL.md' && test -s '.skill-downloads/event-store-design-mrwakcrw/SKILL.md' && mkdir -p '.claude/skills' && test ! -e '.claude/skills/event-store-design' && cp -R '.skill-downloads/event-store-design-mrwakcrw' '.claude/skills/event-store-design'Cursor
test -f '.skill-downloads/event-store-design-mrwakcrw/SKILL.md' && test -s '.skill-downloads/event-store-design-mrwakcrw/SKILL.md' && mkdir -p '.cursor/skills' && test ! -e '.cursor/skills/event-store-design' && cp -R '.skill-downloads/event-store-design-mrwakcrw' '.cursor/skills/event-store-design'Codex
test -f '.skill-downloads/event-store-design-mrwakcrw/SKILL.md' && test -s '.skill-downloads/event-store-design-mrwakcrw/SKILL.md' && mkdir -p '.agents/skills' && test ! -e '.agents/skills/event-store-design' && cp -R '.skill-downloads/event-store-design-mrwakcrw' '.agents/skills/event-store-design'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/event-store-design-mrwakcrw'openskills read 'event-store-design-mrwakcrw'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.
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Read .skill-downloads/event-store-design-mrwakcrw/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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