General-purpose reliable UDP with C99 hot path and Haskell protocol logic.

A general-purpose reliable UDP networking library. C99 hot path (serialization, send/recv, ack processing, crypto) for maximum performance on any platform. Haskell protocol brain (connection state machines, congestion control, replication) for correct-by-construction logic. Successor to gbnet-hs.

What is nova-net?

A general-purpose reliable UDP networking library. C99 handles the hot path (serialization, send/recv, ack processing, crypto). Haskell handles the protocol logic (connection state machines, congestion control, replication).

• C99 hot path — packet serialization, socket I/O, ACK bitfield processing, CRC32C, ChaCha20-Poly1305. No heap allocation on the hot path.
• Haskell protocol brain — connection state machines, handshake orchestration, congestion control, replication. Pure, testable, correct-by-construction.
• Unsafe FFI boundary — Haskell calls C with zero marshalling overhead. Just a function pointer jump.
• Any platform — C99 core compiles everywhere. Link from Haskell, Swift, Kotlin, Python, Zig, anything.
• Effect abstraction — MonadNetwork typeclass enables pure deterministic testing with no real sockets.

Architecture

┌─────────────────────────────────────────┐
│           User Application              │
├─────────────────────────────────────────┤
│  Haskell Protocol Brain                 │
│  Connection, Peer, Handshake,           │
│  Congestion, Replication                │
├─────────────────────────────────────────┤
│  Unsafe FFI Boundary                    │
│  foreign import ccall unsafe            │
├─────────────────────────────────────────┤
│  C99 Hot Path                           │
│  nn_packet, nn_serialize, nn_socket,    │
│  nn_reliability, nn_crypto, nn_channel  │
└─────────────────────────────────────────┘

Features

• 68-bit packet headers (4-bit type + 16-bit seq + 16-bit ack + 32-bit ack bitfield)
• 5 delivery modes (Unreliable, UnreliableSequenced, ReliableUnordered, ReliableOrdered, ReliableSequenced)
• Dual-layer congestion control (binary mode + TCP New Reno window)
• ChaCha20-Poly1305 AEAD encryption with anti-replay
• Jacobson/Karels RTT estimation with adaptive retransmit
• Large message fragmentation and reassembly
• Connection migration
• Delta compression, interest filtering, priority accumulation, snapshot interpolation

Build & Test

Requires GHCup with GHC >= 9.8.

cabal build                              # Build library
cabal test                               # Run all tests
cabal build --ghc-options="-Werror"      # Warnings as errors
cabal bench                              # Run benchmarks

Contributing

cabal test && cabal build --ghc-options="-Werror"

_{BSD-3-Clause · Novavero AI}.