Lux Warp — Cross-Chain Messaging

Lux is not merely adding post-quantum signatures to a chain; it defines a hybrid finality architecture for DAG-native consensus, with protocol-agnostic threshold lifecycle, post-quantum threshold sealing, and cross-chain propagation of Horizon finality.

See LP-105 §Claims and evidence for the canonical claims/evidence table and the ten architectural commitments — single source of truth.

Cross-chain messaging protocol for the Lux Network. Source-chain validators sign an outbound message; the destination chain verifies the signature against the source's registered validator set.

Versions

Version	Lanes	Status	Source
Warp 1.x	Beam (BLS aggregate)	shipping	message.go, signature.go
Warp 2.0	Beam + ML-DSA cert set + Pulse (Pulsar threshold)	shipping	envelope.go, pulsar/
Warp Private	FHE ciphertext + Pulse	production-research	LP-021v2 (forthcoming)

Warp 1.x is the byte-equal fast classical path: a single BLS12-381 aggregate plus a signer bitmap (LP-075). Warp 2.0 is the Prism-bound hybrid envelope — it carries the Warp 1.x message intact alongside the Pulsar threshold pulse and the per-validator ML-DSA attestation set, all bound to a common source-chain transcript (LP-105 §"Warp evolution"). Warp Private adds Z-Chain FHE ciphertext semantics on top.

Architecture

github.com/luxfi/warp
├── message.go         UnsignedMessage, Message — Warp 1.x core types
├── signature.go       BitSetSignature, BLS signing functions
├── validator.go       Validator, CanonicalValidatorSet, ValidatorState
├── envelope.go        EnvelopeV2 — Warp 2.0 envelope + dispatcher
├── verifier.go        Verifier interface
├── handler.go         P2P Handler interface
├── pulsar/            Warp 2.0 Pulse path (KernelVerifier, BuildSigningBytes)
├── payload/           Payload types (AddressedCall, Hash, ...)
├── backend/           Backend, MemoryBackend, ChainBackend
├── signer/            Signer interface (LocalSigner, RemoteSigner)
├── signature-aggregator/  Signature aggregation API
├── relayer/           Message relaying
├── precompile/        EVM precompile integration
├── docs/              Fumadocs documentation site
└── cmd/               CLI tools

The pulsar/ subpackage is split out so the root warp package does not import the Pulsar kernel directly — the dispatch surface is the small PulseVerifier interface; the concrete kernel-driven verifier lives in pulsar/.

Wire format dispatch

            +-----------------------+
incoming -> | first byte == 0x02?   |
            +-----------------------+
                 |yes        |no
                 v           v
         ParseEnvelopeV2   ParseMessage  (Warp 1.x bare RLP message)
                 |           |
                 v           v
            EnvelopeV2 (PQ lanes populated when present)

Use warp.ParseEnvelope(b) for receivers that want forward compatibility across both versions; it returns a v2 envelope in both cases (with PQ lanes empty on v1 inputs).

Compatibility properties

• Forward (v2 receiver, v1 bytes): ParseEnvelope decodes a v1 message into an EnvelopeV2 with only the Beam lane populated. PQ fields are zero-valued; HasPulse() and HasMLDSACertSet() return false.
• Backward (v1 receiver, v2 bytes): a v1 receiver calling ParseMessage directly on v2 wire bytes rejects them — the leading 0x02 is not a valid RLP-list prefix. This is the correct refusal: a v1 verifier cannot validate v2 transcript binding. Senders that must reach v1-only verifiers emit Warp 1.x bytes on the v1 channel; the same UnsignedMessage may be embedded in a v2 envelope on the v2 channel without re-signing the Beam.
• Embedding stability: EnvelopeV2.ID() returns the same hash as the embedded Message.ID(), so destination-chain replay protection is uniform across versions.

Verifying a Warp 2.0 envelope

The standard verification chain (warp.VerifyV2) checks lanes in order:

1. Structural envelope invariants.
2. Hash-suite consistency (when caller pins HashSuiteID).
3. Beam lane: BLS aggregate vs the source-chain validator set + quorum.
4. ML-DSA cert set lane (when configured / required).
5. Pulsar Pulse lane (when configured / required).

A receiver that has already validated the Beam through a separate code path can call warp.VerifyPQLanes to layer in PQ-lane checks without re-running BLS aggregate verification.

Pulse path (warp/pulsar)

The Pulse component binds to the source-chain Pulsar lineage. The canonical signing bytes are produced by pulsar.BuildSigningBytes:

WARP-PULSAR-ENVELOPE-v1 ||
    source_chain_id      || (32 bytes)
    source_nebula_root   || (32 bytes)
    source_key_era_id    || (8 bytes BE)
    source_generation    || (8 bytes BE)
    hash_suite_id_len    || hash_suite_id
    unsigned_message_len || unsigned_message_bytes

The destination chain implements the pulsar.GroupKeyResolver interface against its source-chain key registry — a contract that records the source's GroupKey lineage as it evolves through Bootstrap, Reshare, and Reanchor events (LP-073 §"Key-Era Lifecycle").

Usage (Warp 1.x)

import "github.com/luxfi/warp"

unsigned, _ := warp.NewUnsignedMessage(networkID, sourceChainID, payload)
msg, _ := warp.SignMessage(unsigned, signers, validators)
err := warp.VerifyMessage(msg, networkID, validatorState, 2, 3)

Usage (Warp 2.0)

import (
    "github.com/luxfi/warp"
    warppulsar "github.com/luxfi/warp/pulsar"
)

env := &warp.EnvelopeV2{
    Message:          v1Msg,                  // signed Warp 1.x message
    SourceNebulaRoot: nebulaRoot,
    SourceKeyEraID:   eraID,
    SourceGeneration: generation,
    HashSuiteID:      warp.DefaultHashSuiteID,
    PulsarPulse:      pulseBytes,             // optional
    MLDSACertSet:     certSetBytes,           // optional
}
wire, _ := env.Bytes()

// Receiver:
parsed, _ := warp.ParseEnvelope(wire)
err := warp.VerifyV2(parsed, warp.VerifyV2Options{
    NetworkID:      networkID,
    ValidatorState: validatorState,
    QuorumNum:      2,
    QuorumDen:      3,
    Pulse:          warppulsar.NewKernelVerifier(myResolver),
    RequirePulse:   true,
})

References

• LP-021 — Warp 1.x classical Beam-only cross-chain messaging.
• LP-021v2 — Warp 2.0 hybrid envelope (this implementation; spec doc forthcoming, vocabulary stub in LP-105 §"Warp evolution").
• LP-073 — Pulsar lattice threshold kernel.
• LP-075 — BLS aggregate (Beam).
• LP-105 — Lux Stack Lexicon (Beam, Pulse, Prism, Horizon, etc.).

Module path

github.com/luxfi/warp. Build & test with GOWORK=off go test ./....