Case study 02 / 07 · ● Live · 2026
MSDL
Get official Windows ISOs directly from Microsoft's CDN — no account, no MCT.
An open-source tool for getting official Windows ISO files from Microsoft's CDN without an account or the Media Creation Tool. It supports 38 languages and ARM64, x64, and x86. The frontend is React 19, TypeScript, and Tailwind v4; the backend is Go 1.22 on net/http with RWMutex-cached session parsing, running on a VPS over direct HTTP.
- Go
- React 19
- TypeScript
- Tailwind CSS v4
- Framer Motion
Microsoft requires an account and the Windows-only Media Creation Tool to download ISOs, which leaves out Linux, macOS, and IT admins who script rollouts.
Reverse-engineers the session-registration flow used by Rufus’s Fido.ps1 and rebuilds it as a stateless Go proxy that any platform can call.
At real traffic volume, Microsoft returns error 715-123130 and blocks the calling IP, so the caching architecture exists to scale without overloading Microsoft’s servers.
Highlights
- A 4-layer cache (SKUs, signed links, eval redirects, negative results) with jittered TTLs
- singleflight collapses 500 concurrent cache misses into one outbound Microsoft call
- The CLI sends fetches back to warm the cache the website reads from
- Distributed as a web app and CLI through winget, Homebrew, a curl installer, raw binaries, and Termux/Android
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