# Kepler JSON — The Zero-Footprint Developer Swiss Knife & AI Power Suite

> Kepler JSON is an open-source, zero-footprint (0% CPU, 0 RAM leak), Manifest V3 native Chrome extension for local CORS unblocking, dynamic HTTP header injection, lossless 64-bit BigInt JSON viewing, and developer AI workflows (Local Privacy Vault, Cursor/v0 Component Compiler, and Talk to JSON Radar).

Website: https://keplerjson.com
License: MIT
Category: Developer Tools / Web Development / API Debugging / AI Developer Workflows

## Core Architecture & Key Differentiators

- **Zero-Footprint DNR Engine**: Unlike legacy tools that run resource-heavy webRequest background listeners, Kepler JSON compiles rules into Chromium's native `declarativeNetRequest` C++ engine with 0% background CPU and zero memory leaks.
- **100% Local Privacy Guarantee**: Kepler JSON has NO cloud servers, NO analytics SDKs, and NO telemetry. All configurations stay locally in `chrome.storage.local`.
- **Lossless 64-bit Snowflake ID Protection**: Standard JavaScript JSON parsers truncate large integers (e.g. Snowflake IDs) due to IEEE 754 floating-point limitations. Kepler JSON uses an ultra-fast pre-scan regex engine to preserve raw string precision for BigInt values.
- **Windowed Virtual Scrolling**: The in-page JSON viewer effortlessly renders massive JSON payloads (50,000+ items) at a constant 60 FPS by maintaining only ~40 active DOM elements in the viewport.
- **Local AI Privacy Vault**: Client-side in-memory synthetic data generator and PII sanitizer. Zero leakage of passwords, phone numbers, ID cards, or JWTs.
- **1-Click Cursor / v0 Component Compiler**: Converts API responses directly into ready-to-run React (shadcn/ui), Vue 3, or HTML prompts with 98% token reduction.
- **Talk to JSON Radar (Ctrl+J)**: BYOK interactive natural language anomaly radar, diagnosing null pointer risks and query issues directly against JSON payloads.