NEXUS Mesh

NEXUS Mesh is a non-custodial verification and settlement mesh addressing machine-to-machine micropayments for IoT devices and autonomous agents. By combining the HTTP 402 Payment Required standard with Algorand's sub-three-second deterministic finality, it lets resource servers verify and settle micro-transactions atomically without each server maintaining its own blockchain infrastructure. To keep the mesh from becoming a hidden custodian or single point of failure, the infrastructure is decoupled into seven security modules: a compatibility layer enforcing protocol versioning and rejecting unsupported scheme and network pairs; a facilitator registry handling capability discovery, health checks and circuit-breaker routing; a verification service validating Ed25519 signatures, exact pricing parameters and expiration windows; a settlement service driving an explicit state machine through idempotency claim, verification, settling and confirmation; a receipt service binding payments to a zero-ALGO note field and issuing HMAC-signed off-chain receipts; an observability console tracing lifecycle events to the fulfilment webhook; and a read-only extension interface passing payment semantics strictly by value.