Transactions

The Midnight node supports the standard Polkadot SDK transaction format, but these default-style transactions are uncommon in practice. Midnight relies on a proof-based verification model that is tightly coupled with the Midnight Ledger design.

Most Midnight transactions are unsigned and follow a format defined by the Midnight Ledger. Instead of traditional signature-based authorization, these transactions embed a cryptographic proof that attests to the validity of a specific action, such as a contract invocation, contract deployment, or ZSwap transaction. This proof lets the network validate state transitions without exposing sensitive data or signatures directly.

When a transaction is submitted, it passes through several processing stages. First, the transaction pool validates its well-formedness, ensuring it meets the structural and logical requirements defined by the runtime and ledger specification.

Once a block includes the transaction, the runtime fully verifies the embedded proof. If the proof is valid, the runtime executes the corresponding state transition. It then commits the resulting state update to on-chain storage, completing the transaction lifecycle.