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Build your own BitTorrent

Learn about .torrent files, the BitTorrent Peer Protocol and more

Start Building
bittorrent
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Python
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Rust
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C
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C++
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C#
bittorrent
Elixir
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Haskell
bittorrent
Java
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JavaScript
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Kotlin
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Ruby
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Zig
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TypeScript
This challenge is free until 1 November 2024!

BitTorrent is a peer-to-peer file sharing protocol used for distributing large amounts of data. In this challenge, you'll build a BitTorrent client that's capable of downloading a publicly available file using the BitTorrent protocol.

Along the way, you'll learn about the BitTorrent protocol, .torrent files more.

Stages

Decode bencoded strings
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Decode bencoded integers
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Decode bencoded lists
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Decode bencoded dictionaries
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Parse torrent file
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Calculate info hash
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Piece hashes
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Discover peers
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Peer handshake
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Download a piece
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Download the whole file
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Magnet Links

Parse magnet link
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Announce extension support
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Send extension handshake
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Receive extension handshake
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Request metadata
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Receive metadata
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Download a piece
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Download the whole file
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“ There are few sites I like as much that have a step by step guide. The real-time feedback is so good, it's creepy! avatar Ananthalakshmi Sankar Automation Engineer at Apple “ I think the instant feedback right there in the git push is really cool. Didn't even know that was possible! avatar Patrick Burris Senior Software Developer, CenturyLink