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The Sei Giga Whitepaper V2 is a major update to the original Giga Whitepaper published in May 2025. It introduces significant performance improvements and new features to Sei Giga, redesigning Sei Network from first principles into a blockchain with the ideal architecture for onchain trading.Read the full whitepaper at: https://arxiv.org/pdf/2505.14914
What's New in V2The updated whitepaper addresses the questions the original left open. Where v1 described how Giga achieves speed and throughput, V2 adds how it will solve for privacy and fairness.
Faster FinalityThe new whitepaper introduces even faster performance for Giga's Autobahn consensus protocol. It now targets sub-250ms finality, down from the 400ms target in the original whitepaper. This will be delivered while maintaining 200,000+ transactions / 5 gigagas per second throughput across the network’s decentralized validator set.
Pre-Execution Privacy and MEV ResistanceThe new whitepaper introduces Sedna, a private transaction layer.
Transactions on Sei Giga will be encoded into fragments and distributed across multiple proposer lanes. This will ensure that no proposer will see the full contents of a transaction until ordering is finalized, giving the network pre-execution privacy. In short, a trade will never be visible until it is executed.
It also introduces a deterministic mechanism for ordering transactions across proposer lanes. This will make transaction ordering transparent, predictable, and secure against manipulation by any individual proposer.
Ultimately, Sedna will almost completely remove the MEV and censorship risk that affects every other smart contract blockchain.
The original Giga breakthrough: multi-proposer consensusIn traditional blockchains, one validator at a time is chosen to propose a block. That validator collects transactions, builds the block, broadcasts it, and then everyone votes on it across multiple rounds before it's finalized. Everything happens in sequence. You can't start the next block until the current one finishes the full propose-vote-vote-commit cycle. The speed of the entire chain is bottlenecked by one proposer at a time and multiple rounds of back-and-forth messaging.
Autobahn throws out that sequential model. Instead of one leader proposing blocks while everyone else waits, every validator will run its own "lane" and continuously stream batches of transactions in parallel. Each validator will propose independently and get a lightweight proof that its data is available from a small quorum of peers -- without requiring everyone to download everything upfront. A designated leader will then periodically take a snapshot called a "tip cut" that will capture the latest batch from every lane and commit them all at once through a streamlined two-phase vote.
This is what will enable Sei Giga’s immense throughput. Instead of being limited to however many transactions one validator can fit into one block per round, every validator will produce data simultaneously, and the consensus layer will synthesize their outputs together, sorting them deterministically by priority fee. The raw throughput ceiling will go from "one proposer's bandwidth" to the aggregate bandwidth of the entire validator set.
The Optimal Design for Institutional TradingBlockchains offer significant advantages over traditional trading venues. These include near instant settlement, shared liquidity, composability and 24/7 markets. However, in spite of these advantages, traditional traders are yet to adopt blockchain technology at scale.
For a trading environment to be successful, it has to be predictable. Trading on layer one blockchains today, because of the risks posed by MEV and possible censorship from block builders, is not predictable. This makes today’s blockchains fundamentally unsuitable for institutional traders.
When trading has taken off onchain, it has done so on venues which make the tradeoff of adopting centralized designs in order to make market structure more predictable. However in doing so, these exchanges expose themselves to the same centralization risks that affect legacy trading venues.
Sei's Giga upgrade will take the completely novel approach of introducing a multi-proposer architecture, and combining it with a private transaction dissemination layer. The result will be the first layer one blockchain that is actually suited for trading at scale. Sei Giga will offer pre-execution privacy, fair transaction ordering, MEV resistance, and censorship resistance while ensuring high throughput and near instant settlement.
Sei Giga will be the blockchain for trading.
What's NextSei Labs is well underway with the Giga Upgrade. Progress towards Giga can be followed on Sei Labs’ Giga Roadmap.
The whitepaper's future work section outlines several areas of active development:
Full transaction fee mechanism Autobahn consensus upgradesNew tokenomics for the SEI token The Giga upgrade will be the most complex blockchain upgrade since Ethereum's Merge. The network will transition to the full Giga protocol without regenesis and without taking any element of the network offline.
Read the full whitepaper: https://arxiv.org/pdf/2505.14914
Disclaimer: The roadmap is subject to change based on development progress, market feedback, and other factors. Actual timelines, figures, and outcomes may vary.