{"slug": "show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry", "title": "Show HN: Castov – Open-source dev tools and AI secret shield with zero telemetry", "summary": "Castov launched as an open-source developer toolkit that runs 13 utilities locally across a web interface, a CLI invoked via `npx castov`, and a Model Context Protocol server for use inside Cursor or Claude, with the project claiming zero telemetry and no server-side logging of inputs. The toolkit bundles cryptography and JWT inspection via WebCrypto, JSON-to-TypeScript conversion, cron and timezone tools, encrypted URL-hash sharing, RSA-OAEP-encrypted Team Vaults synced through GitHub OAuth, and a Docker image published as castovdev/castov on Docker Hub. Castov also offers a WebRTC/Yjs peer-to-peer node editor for data pipelines and steganographic storage of AES keys in image pixels, positioning the project around keeping developer secrets out of third-party servers.", "body_md": "# The Complete Developer Toolkit \n\nWeb + CLI + AI (MCP)\n\nAll your mission-critical utilities executed locally in your browser, terminal, and AI agents. Zero server tracking, sub-millisecond transforms, and seamless multi-stage pipelines.\n\n`Ctrl + K`\n\n`npx castov`` castov mcp`\nSimulates the full `castov-cli` suite locally via WebCrypto and instant transforms.\n\nClick any quick-run chip above or type `help` to see commands.\n\n[CLI Docs](https://castov.com/cli)\n\n## Why Developers Choose Castov\n\nFive architectural decisions that make Castov the preferred toolkit for modern software teams.\n\n### Zero-Data Logging\n\nWebCrypto\n100% of cryptography, JWT inspection, JSON formatting, and timestamp parsing executes in local browser memory. Not a single keystroke is sent to external servers.\n\n### Tool Pipelines (\"Pipe to...\")\n\nChaining\nPass outputs seamlessly across utilities in one click: JSON directly to TypeScript interfaces, Cron schedules into world timezones, and diffs to schema generators without clipboard juggling.\n\n### Unified Ecosystem\n\nWeb • CLI • MCP\nThe exact same 13 utilities work on the Web, in your local terminal via `castov`, and inside Cursor or Claude via our Grade-A certified Model Context Protocol server.\n\n### Encrypted URL Shares\n\nZero-Server\nShare inputs, diffs, and settings with teammates instantly. Payloads are compressed into the URL hash fragment (`#`) so servers never see what you shared.\n\n### E2EE Cloud Sync & Team Vaults\n\nGitHub OAuth\nZero-friction leverage unlocked on registration\n\n[Connect Workspace](https://castov.com/account)\n\nConnect your GitHub account to sync pinned utilities, presets, and dev preferences across all your machines. Collaborate with teammates using RSA-OAEP encrypted Team Vaults to share `.env` files without cleartext exposure in chat channels.\n\n## Deploy Castov Everywhere You Build\n\nWhether inside your local terminal, Docker containers, AI editors, or automated CI/CD pipelines — Castov provides the instant execution layer for developers and MCP AI agents.\n\n### Docker Hub\n\nRun Castov CLI and MCP runtime in an isolated, non-root Alpine container with zero host dependencies.\n\n[Official Registry](https://hub.docker.com/r/castovdev/castov)\n\n```\ndocker run --rm -it castovdev/castov:latest --help\n```\n\n## Advanced Capabilities\n\nWe didn't just build formatters. We built the architecture required by modern engineering teams.\n\n### P2P Multiplayer Canvas\n\nA visual node-editor for building data pipelines. Connects peers in real-time using WebRTC and CRDTs (Yjs) with direct peer-to-peer data channels coordinated through public signaling servers (which may receive connection metadata). Workflow graphs, node configurations, and payload data are never stored on Castov servers.\n\n### Steganography Environment Vaults\n\nEnd-to-end encrypted environment variables. We hide your secure AES keys inside standard image pixels (Steganography) for invisible sharing, entirely in your browser.\n\nTest your frontend without a backend. Our Local API Mocker runs entirely in your browser's Service Worker to simulate payloads globally.\n\n## Explore Our Toolkit\n\nFrom time manipulation to cryptography, everything is beautifully structured and instantly accessible.\n\n## Timestamp\n\n7 tools\n\nConvert, validate, compare and work with Unix timestamps.\n\n## Date & Duration\n\n5 tools\n\nCalculate differences, durations, and add or subtract time from a date.\n\n## Time Zones\n\n6 tools\n\nConvert, compare and browse time across the world's time zones.\n\n## Developer\n\n33 tools\n\nISO 8601, RFC 3339, cron and other formats developers work with daily.\n\n## Labs\n\nExperimental tools\nExperimental tools: WebRTC P2P mesh, steganography, AST parsing, and in-browser WebGL computing.\n\n## Frequently Asked Questions\n\nEverything you need to know about Castov.\n\n## Frequently Asked Questions\n\n## Is Castov really free?\n\n## Is my data sent to a server?\n\n## What is a Unix timestamp?\n\n## Should I use seconds or milliseconds?\n\n## Which time zones are supported?\n\n## Ready to supercharge your workflow?\n\nFree browser-based developer tools. Some collaboration, cloud, and external API features may require an account or additional configuration.", "url": "https://wpnews.pro/news/show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry", "canonical_source": "https://castov.com", "published_at": "2026-10-31 19:30:14+00:00", "updated_at": "2026-10-31 19:51:30.897234+00:00", "lang": "en", "topics": ["developer-tools", "ai-tools", "ai-agents", "agent-protocols"], "entities": ["Castov", "Model Context Protocol", "Cursor", "Claude", "GitHub", "Docker Hub", "WebCrypto", "Yjs"], "also_reported_by": [], "alternates": {"html": "https://wpnews.pro/news/show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry", "markdown": "https://wpnews.pro/news/show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry.md", "text": "https://wpnews.pro/news/show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry.txt", "jsonld": "https://wpnews.pro/news/show-hn-castov-open-source-dev-tools-and-ai-secret-shield-with-zero-telemetry.jsonld"}}