Stop Pasting Production JWTs and Timestamps into Random Websites: Meet Castov (Web, CLI & VS Code)

Description and use

Castov is a local developer toolkit that lets developers convert timestamps, decode JWTs, generate UUIDs, and handle cron expressions without using external sites, reducing data leakage risks and improving workflow efficiency.

Problem

Developers frequently search for tools like epoch converters, JWT decoders, cron generators, or base64 decoders, and often accidentally paste sensitive production data into third‑party websites, creating privacy risks and workflow interruptions.

Outcome

Castov eliminates the need to use external websites for common developer utilities, reducing privacy risk and improving workflow efficiency by keeping all operations local.

Workflow

• Install Castov via npx or npm
• Use CLI commands such as npx castov ts 1700000000 to detect timestamp format
• Run npx castov detect 507f1f77bcf86cd799439011 to extract creation timestamps from IDs
• Explain cron expressions with npx castov cron "*/15 * * * *" UTC
• Generate RFC 9562 UUIDv7 with npx castov uuid -n 5 --v7
• In VS Code, hover over numbers to see date conversions
• Decode JWTs in VS Code with Castov extension
• Use castov-sdk in codebases to generate UUIDv7, parse cron, and decode JWTs

Evidence

To solve both the privacy risk and the context‑switching tax, we built Castov — a unified, zero‑server developer toolkit that runs 100% locally in your browser, your terminal, and Visual Studio Code.

Source

Run it immediately with npx or install globally via npm install -g castov

Source

Hover over any 10 or 13-digit number in your code to see UTC, ISO 8601, and Local dates instantly.

Source