Sei Giga Overview: The Fastest EVM Blockchain

Introduction

Sei Giga represents a high-performance blockchain platform designed to address the persistent challenges of the “blockchain trilemma”: the difficulty of simultaneously optimizing for security, decentralization, and performance. The platform combines current optimizations with upcoming architectural innovations to achieve exceptional performance while maintaining security guarantees and developer experience.

Current Features: Sei operates with Twin Turbo consensus optimizations, parallel execution capabilities, and SeiDB storage, delivering significant performance improvements over traditional blockchains.

Upcoming Features: Advanced features including Autobahn consensus, multi-proposer architecture, and 5 gigagas throughput targets are in development and represent the next evolution of the platform.

Current Architecture

Sei’s current system delivers significant performance improvements through three core components:

1. Twin Turbo Consensus

The current consensus mechanism achieves ~400ms block times through aggressive optimization of the Tendermint BFT consensus engine. Key features include:

Pipelined block processing
Optimistic transaction execution during consensus
Aggressive timeout configurations
Parallel transaction decoding and validation

Learn more about Twin Turbo Consensus →

2. Parallel Execution Engine

Sei implements Optimistic Concurrency Control (OCC) for parallel transaction execution:

Multiple CPU cores process non-conflicting transactions simultaneously
Automatic conflict detection and resolution
Maintains deterministic execution order
Compatible with standard EVM semantics

Learn more about the Parallelization Engine →

3. SeiDB Storage System

A specialized database optimized for blockchain workloads:

Multi-level caching for hot state data
Optimized Merkle Patricia Trie structure
Concurrent state access controls
Efficient state versioning and pruning

Learn more about SeiDB →

Upcoming Sei Giga Architecture

The next evolution of Sei Giga will introduce three key innovations designed to achieve target performance characteristics:

1. Asynchronous Execution Model (Upcoming)

A planned architectural enhancement will implement complete separation of consensus and execution. Unlike traditional blockchains where these processes are tightly coupled, the upcoming Sei Giga architecture will reach consensus solely on the ordering of transactions within a block, not the resulting state change. Asynchronous Execution Architecture

Traditional Blockchain

Order Transactions
Execute & Compute State
Reach Consensus on State
Finalize Block

⚠️ Execution delays consensus

Sei Giga Model

Order Transactions
Consensus on Order
Finalize Block n

Parallel Process:

Execute Block $n - 1$
Commit State in Block $n+x$

✓ Consensus proceeds independently

This approach leverages the key property of deterministic execution: Lemma 1 (Deterministic Execution): Given the same initial state (

S_{init}

) and the same ordered sequence of transactions (

{tx}_1, {tx}_2, ..., {tx}_n

), all honest nodes executing these transactions will arrive at the exact same final state (

S_{final}

). Key benefits of this model:

Non-blocking consensus: Heavy computational blocks don’t delay consensus
Pipelined processing: Multiple blocks can be in different stages simultaneously
Optimized resource usage: Consensus and execution use different hardware resources

2. Autobahn Consensus Protocol (Upcoming)

Future Features: The Autobahn consensus protocol described here represents upcoming enhancements. The current system uses optimized Tendermint consensus (Twin Turbo).

The upcoming Sei Giga will employ Autobahn, a Byzantine Fault Tolerant (BFT) consensus protocol designed for high performance blockchain networks. Unlike traditional single-proposer systems, Autobahn will enable multiple validators to propose blocks simultaneously, targeting significant throughput improvements while maintaining security guarantees. Autobahn Consensus Architecture

Data Dissemination Layer (Lanes)

Lane $\ell_1$ : ${Prop}_1$ , ${Prop}_2$ , ${Prop}_3$ , $Tip$
Lane $\ell_2$ : ${Prop}_1$ , ${Prop}_2$ , $Tip$ , …
Lane $\ell_n$ : ${Prop}_1$ , ${Prop}_2$ , ${Prop}_3$ , $Tip$

Each validator maintains independent lane.

Consensus Layer (Cut Formation)

Cut = [{Tip}_1, {Tip}_2, ..., {Tip}_n]

Periodic ordering of lane tips.

Prepare Phase — Leader collects tips, forms Cut
Fast Path ( $n$ votes) — Immediate commit if all agree
Slow Path ( $2f+1$ votes) — Additional round if needed

Global ordering through BFT agreement.

Protocol Properties

Network Model

n = 3f + 1

replicas

Safety

Unconditional

Liveness

Eventual synchrony

The protocol operates through two complementary layers: Data Dissemination Layer (Lanes):

Each validator maintains an independent lane for proposing transaction batches
Three-step certification process: Propose → Vote → Proof of Availability (PoA)
Chained proposals ensure availability of historical data

Consensus Layer (Cut of Tips):

Periodic ordering of latest certified tips from all lanes
Two-phase BFT agreement with fast and slow paths
Pipelined slots for minimal latency

3. Advanced Parallel Execution

The parallel execution architecture extends beyond current OCC capabilities to include: Parallel Execution Pipeline

Stage 1

Transaction ParsingParallel decode

Stage 2

Dependency AnalysisConflict prediction

Stage 3

Parallel ExecutionMulti-core OCC

Stage 4

State CommitBatch writes

Conflict Detection

Read/Write set tracking
Optimistic execution
Automatic re-execution on conflict
Preserves deterministic ordering

Performance Stats

~65% of ETH txs parallelizable
Linear scaling with cores
Minimal conflict overhead
Zero-copy transaction handling

Key innovations in the execution model:

Flat encoding format: Length-prefixed layout for fast, zero-copy decoding
Predictive conflict analysis: ML-based prediction of transaction dependencies
Semantic understanding: Special handling for common patterns (ERC-20 transfers)
Adaptive parallelism: Dynamic adjustment based on conflict rates

Storage Architecture Evolution

Beyond the current SeiDB capabilities, the Sei Giga architecture includes advanced storage innovations: Hybrid Storage Architecture

Hot Storage Tier

Recent Blocks — High-speed NVMe SSDs
Active State — Memory-mapped files
Access Pattern — Sub-ms latency

Warm Storage Tier

Recent History — Standard SSDs
Compressed State — LZ4 compression
Access Pattern — 1-10ms latency

Cold Storage Tier

Historical Data — Distributed storage
Columnar Format — Analytics optimized
Access Pattern — Batch queries

Cryptographic Layer

Flat KV Store

LSM-tree based

Cryptographic Accumulators

Compact proofs

Write-Ahead Log

Durability guarantee

Economic Model

Sei operates with a native SEI token that serves multiple functions within the ecosystem:

Token Distribution

Total Supply: 10,000,000,000 (10 billion) SEI
Initial Distribution: Allocated across ecosystem participants, validators, and development

Token Utility

Gas Fees: All transactions require SEI for execution
Staking: Validators and delegators stake SEI to secure the network
Governance: SEI holders participate in protocol governance
Rewards: Block rewards and fee distribution to validators

Staking Mechanics

Staking & Validation

Validators

Self-Stake Requirement — Minimum SEI to operate
Commission Rate — Set by validator
Responsibilities — Consensus & execution

Delegators

Delegation — Stake with chosen validators
Rewards — Proportional to stake
Unbonding — 21-day period

Slashing Conditions

Liveness Failures

Penalties for downtime

Safety Violations

Severe penalties for double-signing

Developer Experience

Sei maintains full EVM compatibility while providing enhanced capabilities:

Standard EVM Features

Complete support for Solidity and Vyper
Standard JSON-RPC endpoints
Compatible with existing tools (Hardhat, Foundry, Remix)
Familiar development workflow

Enhanced Capabilities

Sub-second transaction finality
Predictable gas costs
High throughput for complex applications
Advanced storage access patterns

Implementation Status

Current & Upcoming Features

Current Implementation — Live on Mainnet

Twin Turbo Consensus

~400ms blocks

Parallel Execution

Multi-core processing

SeiDB Storage

Optimized state access

Upcoming Features — In Development

Autobahn Consensus

Multi-proposer protocol

5 Gigagas Throughput

Performance target

Advanced Optimizations

Enhanced execution

Learn More

Explore the technical components that make Sei’s performance possible:

​Introduction

​Current Architecture

​1. Twin Turbo Consensus

​2. Parallel Execution Engine

​3. SeiDB Storage System

​Upcoming Sei Giga Architecture

​1. Asynchronous Execution Model (Upcoming)

Traditional Blockchain

Sei Giga Model

​2. Autobahn Consensus Protocol (Upcoming)

Data Dissemination Layer (Lanes)

Consensus Layer (Cut Formation)

Network Model

Safety

Liveness

​3. Advanced Parallel Execution

Stage 1

Stage 2

Stage 3

Stage 4

Conflict Detection

Performance Stats

​Storage Architecture Evolution

Hot Storage Tier

Warm Storage Tier

Cold Storage Tier

Flat KV Store

Cryptographic Accumulators

Write-Ahead Log

​Economic Model

​Token Distribution

​Token Utility

​Staking Mechanics

Validators

Delegators

Liveness Failures

Safety Violations

​Developer Experience

​Standard EVM Features

​Enhanced Capabilities

​Implementation Status

Current Implementation — Live on Mainnet

Twin Turbo Consensus

Parallel Execution

SeiDB Storage

Upcoming Features — In Development

Autobahn Consensus

5 Gigagas Throughput

Advanced Optimizations

​Learn More

Introduction

Current Architecture

1. Twin Turbo Consensus

2. Parallel Execution Engine

3. SeiDB Storage System

Upcoming Sei Giga Architecture

1. Asynchronous Execution Model (Upcoming)

2. Autobahn Consensus Protocol (Upcoming)

3. Advanced Parallel Execution

Storage Architecture Evolution

Economic Model

Token Distribution

Token Utility

Staking Mechanics

Developer Experience

Standard EVM Features

Enhanced Capabilities

Implementation Status

Learn More