App Modernization & Platform Upgrade
Modernize an existing application without rebuilding it from scratch. This bundle helps understand legacy code, identify and repair codebase issues, migrate JavaScript to TypeScript, add feature flags, audit logs, admin dashboards, and multi-tenant SaaS support. Use it when an older or fast-growing application needs stronger maintainability, safer change control, better operations, and a cleaner platform foundation.
Works with every agent that reads SKILL.md — Claude Code, Cursor, Codex CLI, Gemini CLI, GitHub Copilot, Windsurf, OpenClaw, and more.
One payment, lifetime access. 8 skills unlock instantly in your library.
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Free updates from the creator
What's included
8 skills
Automatically add feature flags to existing applications.
Automatically build secure admin dashboards inside existing applications.
Automatically add secure audit logging to existing applications.
Automatically add secure multi-tenant architecture to existing SaaS applications.
Automatically migrate JavaScript projects to TypeScript without rewriting everything at once.
Automatically detect and fix issues in your codebase.
Struggling to understand a new codebase? This skill breaks down complex codebases into clear explanations, key components, and a step-by-step onboarding path...
Understand and improve messy legacy code fast.
See it in action
Add Feature Flags Automatically
Example session with this skill installed
Add a feature flag for a new payment gateway in my Express app. It should be disabled by default and only active for users with the 'beta-tester' role.
- Read your context and instructions
- Compiled the add feature flags
Project Detected: Express.js (Node.js)
Feature Flag Added
- Flag: billing.gateway.new_provider
- Controls: New payment processing logic
- Default: disabled
Rollout Rules
- Role-based targeting (beta-tester)
- Fallback: Default to legacy gateway
Implementation Summary
- Created services/flags.js
- Updated routes/payments.js to check flag
- Added flag to .env.example
Files Modified
- services/flags.js
- routes/payments.js
- .env.example
Commands Executed
- npm test
Validation Result
Verified that users without the beta-tester role fall back to legacy gateway.
How to install
Works the same in every agent - Claude, Cursor, Codex, Copilot and 20+ more.
- 1
Download the ZIP
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- 2
Unzip into your skills folder
Every agent reads skills from one folder on your machine. Drop the unzipped folder in there.
- 3
Ask your agent to use it
Restart the agent if it was already running. It picks the skill up automatically - no config needed.
Skills folder by agent
Click the path to copy it. Create the folder if it does not exist yet.
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