// the find
imputnet/cobalt
best way to save what you love
Cobalt is a self-hostable media downloader that extracts video and audio from 20+ platforms (YouTube, TikTok, Instagram, Twitter, etc.) without ads, tracking, or rate-limiting paywalls. It works as a proxy — it never stores your content, just tunnels the stream. The target audience is people who want a clean, API-accessible alternative to sketchy download sites, or developers who want to build on top of a documented download API.
The proxy-stream architecture is the right call — nothing touches disk on the server, which sidesteps most content liability concerns and keeps memory pressure low. The monorepo is well-structured: API (Node.js), web (SvelteKit), and packages are cleanly separated with their own READMEs and licenses, which matters when the API and frontend have different deployment lifecycles. There's a real test suite with per-service JSON fixtures under `api/src/util/tests/`, so regressions in YouTube or TikTok parsing show up before they hit users. The cipher randomization (`randomize-ciphers.js`) is a practical touch — it helps avoid TLS fingerprinting blocks that would otherwise kill the YouTube and Instagram pipelines.
The entire thing is one TOS violation away from being shut down for any given platform — Instagram and TikTok actively fight scrapers, and there's no fallback strategy when a service blocks the instance IP. Self-hosting is non-trivial: you need to manage cookies for authenticated services, wire up Redis for rate limiting, handle Cloudflare Turnstile for the public instance's bot protection, and keep up with platform-side changes that break extractors (no versioned stability guarantee here). The API is JavaScript with no TypeScript except in the web client — the service extractors are plain `.js` with inline validation, so adding a new service or debugging a broken one means reading undocumented internal conventions. Only English and Russian are supported in the UI translations, which is a narrow reach for a tool with clear global demand.