Overview
fullstack-guardian is an open-source backend skill for Claude Code and compatible agents, published by Jeffallan. Its author describes it as: “Builds security-focused full-stack web applications by implementing integrated frontend and backend components with layered security at every level. Covers the complete stack from database to UI, enforcing auth, input…”. The project has 11k stars on GitHub and is available under the MIT license. Add it to your setup with `/plugin marketplace add Jeffallan/claude-skills`.
What fullstack-guardian does
Security-focused full-stack developer implementing features across the entire application stack.
Best for
What’s inside
The SKILL.md for fullstack-guardian is organised into these sections:
- Core Workflow
- Reference Guide
- Constraints
- MUST DO
- MUST NOT DO
- Three-Perspective Example
- Output Templates
Installation
Add fullstack-guardian to your agent with:
/plugin marketplace add Jeffallan/claude-skillsReview a skill’s source before installing it — skills can instruct your agent to run commands. This command comes from the skill’s public repository, which is the source of truth for setup steps. New to skills? Read how to install Claude Code skills.
Supported agents
- Claude Code — ships a claude code plugin marketplace
License
fullstack-guardian is published under the MIT license.
Strengths
- Clear MIT license — safe to read and adapt within its terms
- Ships in Jeffallan/claude-skills, an established project with 11,060 GitHub stars
- Works with Claude Code
- Actively maintained — repository updated in the last 90 days
Author
Topics
Frequently asked questions
- What does fullstack-guardian do?
- Builds security-focused full-stack web applications by implementing integrated frontend and backend components with layered security at every level. Covers the complete stack from database to UI, enforcing auth, input validation, output encoding, and parameterized queries across all layers. Use when implementing features across frontend and backend, building REST APIs with corresponding UI, connecting frontend components to backend endpoints, creating end-to-end data flows from database to UI, or implementing CRUD operations with UI forms. Distinct from frontend-only, backend-only, or API-only skills in that it simultaneously addresses all three perspectives—Frontend, Backend, and Security—within a single implementation workflow. Invoke for full-stack feature work, web app development, authenticated API routes with views, microservices, real-time features, monorepo architecture, or technology selection decisions.
- How do I install fullstack-guardian?
- Run /plugin marketplace add Jeffallan/claude-skills in your agent, then reload your skills. Review the source at https://github.com/Jeffallan/claude-skills before installing.
- Is fullstack-guardian free to use?
- Yes. fullstack-guardian is free and open source under the MIT license, so you can read, run, and adapt it within that license's terms.
- Which agents does fullstack-guardian work with?
- fullstack-guardian lists Claude Code — named in its SKILL.md, its plugin marketplace or its repository topics. Skills use the portable SKILL.md format, so other agents that read that format may load it too.
- Where does fullstack-guardian come from?
- fullstack-guardian ships inside Jeffallan/claude-skills, a repository that contains 41 catalogued skills in total. The repository's 11,060 GitHub stars apply to that whole collection, not to this skill on its own.