Midnight Node 2.1.0 RC2 Fixes Bridge Costs and Node Bootstrap

Midnight released Node 2.1.0 RC2 on September 17, removing two technical blockers that had prevented the 2.1 line from advancing toward a final release.

The update introduces no new protocol behavior, but changes how the runtime is verified, how bridge workloads are measured and how new nodes connect to Preview and Devnet.

Midnight Publishes a Verifiable Runtime

Midnight Node 2.1.0 RC2 is the first candidate in the 2.1 line to include a deterministic runtime WASM file and an accompanying srtool digest documenting how it was produced.

The runtime WASM contains the logic executed by Midnight nodes. A deterministic build allows operators and governance participants to confirm that the published artifact corresponds to the source code.

RC1 did not include a separate WASM artifact. Governance therefore lacked an independently reproducible file that could be referenced when authorizing an upgrade through a set_code action.

RC2 now provides the runtime file, cryptographic hashes and build provenance required for verification. A coordinated governance action is still required to activate the runtime, but the necessary technical artifact is now available.

The release contains five additional commits compared with RC1. It does not change the protocol specification or introduce new user-facing functionality, keeping its scope focused on final release preparation.

Midnight Corrects Cardano Bridge Costs

New benchmark testing found that functions inside pallet_c2m_bridge and pallet_partner_chains_bridge had been assigned approximately half their actual execution cost on reference validator hardware.

The earlier weights were generated on a developer workstation rather than Midnight’s designated benchmarking machine. After the tests were repeated on the reference hardware, the measured weights for bridge operations increased by between 1.92 and 2.51 times.

The update does not make the operations more computationally expensive. It gives the runtime a more accurate measure of resources that were already being consumed.

One affected function, handle_transfers, is executed as a mandatory part of a block. An underpriced mandatory call can push block processing beyond its intended resource limit because the operation cannot be deferred when the remaining capacity has been consumed.

The corrected components include the Cardano-to-Midnight bridge and Cardano observation infrastructure associated with cNIGHT. These systems connect Cardano-based NIGHT activity with the Midnight chain. More accurate resource pricing aligns bridge capacity with the measured cost of processing NIGHT-related operations on validator hardware.

Genesis Fix Restores New Node Bootstrap

RC2 also replaces the packaged chain specifications and genesis artifacts for Preview and Devnet.

A node launched from an empty disk with earlier files could calculate an incorrect genesis hash. Existing bootnodes would identify it as belonging to another chain and reject the connection, leaving the affected node at block zero without peers.

The defect does not affect nodes that are already connected and synchronized because their valid genesis data is stored locally. Operators with affected new installations must remove the existing base path and bootstrap again using the files included with RC2.

Already synchronized nodes do not require a reset, resynchronization or reindexing. There is also no supported direct upgrade path from RC1 or the earlier beta because those versions were development candidates rather than deployment baselines. The supported path remains a coordinated hard fork from the 1.0.300 runtime.

Midnight 2.0 never reached a final release, making 2.1.0 the planned first completed version of the new major line after Node 1.0.1. RC2 is not a final mainnet release, but governance now has a verifiable runtime artifact, bridge calls use measured execution costs and new Preview and Devnet nodes can bootstrap with the genesis data used by the active networks.