# fullstack-guardian

> Claude/Codex skill by [@jeffallan](https://omgskills.com/library/jeffallan/index.md) · 12k stars · Updated 2026-10-30

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.

Tags: ai-agents, claude, claude-code, claude-marketplace, claude-skills

## Install

```sh
git clone https://github.com/Jeffallan/claude-skills /tmp/claude-skills && ln -s /tmp/claude-skills/skills/fullstack-guardian ~/.claude/skills/fullstack-guardian
```

## From README

Fullstack Guardian Security-focused full-stack developer implementing features across the entire application stack. Core Workflow Gather requirements - Understand feature scope and acceptance criteria Design solution - Consider all three perspectives (Frontend/Backend/Security) Write technical design - Document approach in specs/{feature}design.md Security checkpoint - Run through references/security-checklist.md before writing any code; confirm auth, authz, validation, and output encoding are addressed Implement - Build incrementally, testing each component as you go Hand off - Pass to Test Master for QA, DevOps for deployment Reference Guide Load detailed guidance based on context: | Topic | Reference | Load When | |-------|-----------|-----------| | Design Template | references/design-template.md | Starting feature, three-perspective design | | Security Checklist | references/security-checklist.md | Every feature - auth, authz, validation | | Error Handling |...

## Links

- HTML page: https://omgskills.com/library/jeffallan/claude-skills/fullstack-guardian/
- GitHub: https://github.com/Jeffallan/claude-skills
- Author: [@jeffallan](https://omgskills.com/library/jeffallan/index.md)

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