▪️Block Building

Block building is the process of selecting pending transactions from the mempool, ordering them according to network rules, executing them, and producing a candidate block to be finalized by Proof-of-Stake consensus. On SATUCHAIN, block building is designed to be predictable and observable so applications, operators, and indexers can rely on consistent execution outcomes.

Overview

A block is produced through three stages:

  1. Transaction Selection The proposer selects valid transactions from the mempool based on network rules and priority.

  2. Execution and State Transition Transactions are executed in order, producing state changes, logs, and receipts.

  3. Block Proposal and Finality The proposer broadcasts the block to validators, which verify it under PoS consensus until finality is reached.

Mempool Intake and Validation

Before a transaction can be considered for inclusion, nodes perform basic validation:

  • correct transaction format and signature

  • valid nonce for the sender account

  • sufficient balance to cover value transfer and fees

  • gas limit and fee fields within protocol constraints

Invalid transactions are rejected and are not propagated.

Transaction Ordering

The proposer orders transactions in a block according to network rules. In general:

  • transactions must respect account nonces (sender order is enforced)

  • higher-fee transactions may be prioritized to improve inclusion speed

  • transactions that fail pre-execution checks are excluded

Ordering impacts execution results, especially for DEX trades, liquidations, and state-dependent calls.

Execution Outputs

Each included transaction produces:

  • Receipt Status, gas used, logs, and other execution fields.

  • Event Logs Indexed topics and data emitted by contracts during execution.

  • State Updates Account balances, storage changes, and contract state transitions.

These outputs are used by explorers, indexers, analytics, and application backends.

Block Contents

A SATUCHAIN block contains:

  • header metadata (block number, timestamp, parent hash)

  • list of transactions

  • receipts and execution-related references

  • hashes required for chain integrity and verification

The explorer and JSON-RPC expose these fields for verification and debugging.

Finality and Reorg Expectations

After a block is proposed:

  • validators verify execution and block validity

  • PoS consensus finalizes the block

  • once finalized, the block becomes canonical

Applications should treat finalized blocks as stable. Pending or non-final blocks may be subject to short reorgs depending on network conditions.

Operational Notes

  • High-volume periods increase mempool size and inclusion competition.

  • RPC nodes should be configured and monitored to ensure stable mempool propagation and block tracking.

  • Indexers should consume blocks, receipts, and logs in order and handle potential short reorgs safely.

Developer Notes

  • Do not rely on transaction ordering beyond protocol guarantees.

  • Use receipts and confirmed block numbers for state transitions in application backends.

  • For time-sensitive flows, track confirmations until the required finality threshold is reached.

Last updated