BUNDLE Security scanned8 skills

    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.

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    Works with every agent that reads SKILL.md — Claude Code, Cursor, Codex CLI, Gemini CLI, GitHub Copilot, Windsurf, OpenClaw, and more.

    Mariusz Wrzeszczynski
    Created by
    Mariusz Wrzeszczynski
    $45.99$65.92
    Save 30% · $19.93

    One payment, lifetime access. 8 skills unlock instantly in your library.

    30-day refund guarantee

    Instant unlock in your library

    Free updates from the creator

    What's included

    8 skills
    1/8
    Add Feature Flags Automatically

    Automatically add feature flags to existing applications.

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    $8.99$6.27Save 30%
    2/8
    Build Admin Dashboards Automatically

    Automatically build secure admin dashboards inside existing applications.

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    $8.99$6.27Save 30%
    3/8
    Add Audit Logs Automatically

    Automatically add secure audit logging to existing applications.

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    $8.99$6.27Save 30%
    4/8
    Add Multitenant Saas Support

    Automatically add secure multi-tenant architecture to existing SaaS applications.

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    $8.99$6.27Save 30%
    5/8
    Migrate Javascript To Typescript

    Automatically migrate JavaScript projects to TypeScript without rewriting everything at once.

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    $8.99$6.27Save 30%
    6/8
    Automatically Fix Issues In Codebase

    Automatically detect and fix issues in your codebase.

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    $6.99$4.88Save 30%
    7/8
    Understand Any Codebase In Minutes

    Struggling to understand a new codebase? This skill breaks down complex codebases into clear explanations, key components, and a step-by-step onboarding path...

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    $6.99$4.88Save 30%
    8/8
    Analyze Legacy Code And Suggest Fixes

    Understand and improve messy legacy code fast.

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    $6.99$4.88Save 30%

    See it in action

    You say

    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.

    Your agent does

    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

    Drop the file into your AI Agent. Works with Claude, Cursor, ChatGPT, and 20+ more.

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    Recently published to Agensi

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    Frequently asked questions

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