Pure C# BitTorrent/WebTorrent client and server. No JavaScript dependencies. Desktop + Browser.

SpawnDev.WebTorrent 1.0.0

• SpawnDev.WebTorrent

Pure C# BitTorrent/WebTorrent client and server. No JavaScript dependencies. Desktop + Browser.

Packages

Package	NuGet
SpawnDev.WebTorrent	Client library — torrents, peers, streaming
SpawnDev.WebTorrent.Server	Server library — tracker, web seed

What's In This Release

Pure C# BitTorrent Implementation

• Complete BitTorrent wire protocol (handshake, bitfield, have, request, piece, cancel, extensions)
• Bencode encoder/decoder with raw key tracking for info hash computation
• .torrent file creation and parsing (single-file, multi-file, magnet URIs, Base32)
• SHA-1 piece verification — every downloaded piece is hash-verified
• BEP 10 extension protocol framework (ut_metadata, ut_pex)

Random-Access Streaming

• ModelStream.ReadAsync(offset, length) — read any byte range from a torrent file as it downloads
• Pieces download on demand when read — only fetch what you need
• Cross-piece reads handled transparently
• Designed for ML model weight loading — tested with forward seek, backward seek, large multi-piece spans, and real ML weight access patterns

Client Library (SpawnDev.WebTorrent)

• WebTorrentClient — full client with peer ID generation, transport management
• PieceManager — piece selection, block tracking, SHA-1 verification, storage
• DownloadCoordinator — ties peers + web seeds together with priority requests
• ModelTorrentClient — high-level API for ML model delivery
• WebSocketTrackerClient — WebSocket tracker with WebRTC signaling relay
• WebSeedConnection — HTTP range request fallback (BEP 17/19)
• TcpTransport — desktop TCP transport
• WebRtcTransport — browser WebRTC transport (structural, JS interop via SpawnDev.BlazorJS)
• PeerCoordinator — full signaling flow: tracker → WebRTC → wire protocol → piece exchange
• MemoryChunkStore + FileChunkStore — pluggable storage backends

Server Library (SpawnDev.WebTorrent.Server)

• TorrentTracker — WebSocket tracker with WebRTC signaling relay for browser peers
• WebSeedServer — serves torrent pieces over HTTP range requests
• MapWebTorrentServer() — one-line ASP.NET endpoint registration

HuggingFace Integration (SpawnDev.WebTorrent.Server.HuggingFace)

• HuggingFaceProxy — fetches model files from HuggingFace CDN, caches locally
• Auto-generates .torrent files with piece hashes on demand
• Magnet URI generation with tracker + web seed URLs
• .torrent file caching — avoids regeneration on repeated requests
• Endpoints: /hf/, /torrent/, /magnet/, /hf-stats

Live Production Server

• hub.spawndev.com — live tracker + HuggingFace proxy serving AI models
• SSL terminated via HAProxy + LetsEncrypt
• Self-contained Linux x64 deployment

Test Suite

• 49 tests passing in Chromium via PlaywrightMultiTest
• 43 unit tests + 6 integration tests against live server
• Stream seeking tests: forward, backward, large span, ML weight loading pattern
• Full end-to-end: browser → server → HuggingFace → cache → .torrent → download → verify

Demo App

• Live Demo — dark theme, live server stats, unit tests
• Blazor WebAssembly — runs entirely in the browser
• GitHub Pages deployment

Why This Exists

AI models are big — 100MB to 2GB+. CDNs can't scale when every user downloads the same model. SpawnDev.WebTorrent turns every browser into a peer. The more users, the faster delivery. Built for SpawnDev.ILGPU.ML — GPU-accelerated ML inference for .NET.

What's Next

• Distributed GPU compute across devices via P2P network
• AcceleratorType.P2P — 7th SpawnDev.ILGPU backend
• AI agent communication protocol over wire extensions
• SpawnDev.WebFS integration (virtual filesystem backed by torrent swarm)
• DHT peer discovery (Kademlia)
• BEP 52 (BitTorrent v2 with SHA-256)

Credits

Built by Todd Tanner (@LostBeard) and the SpawnDev team: Claude (Data), Claude (Riker), Claude (Tuvok), and Gemini.

🖖🚀