Introduction

Since its inception, blockchain technology has been navigating the “impossible trinity” of decentralization, security, and scalability. With the rapid growth of the Ethereum ecosystem and the rise of applications like DeFi, NFTs, and SocialFi, the limitations of the underlying network have become increasingly evident—high gas fees, slow transaction confirmations, and restricted throughput have hindered the mass adoption of decentralized Web3 applications. In response, Layer 2 (L2) scaling solutions have emerged from experimental concepts to become the key to unlocking blockchain’s full potential.

By 2025, the Layer 2 landscape has evolved from a “battle of a hundred schools” to a new era of “ecosystem collaboration and competition.” The two primary approaches, Optimistic Rollup and ZK-Rollup, are advancing rapidly, introducing innovations like enhanced privacy, AI-powered agents, and seamless cross-chain interoperability. Leading projects are not only making strides in scalability but are also redefining how value is captured on-chain. Meanwhile, challenges such as market volatility, tokenomics design, and emerging regulatory frameworks add layers of complexity to the sector’s development.

This article examines the technological advancements, ecosystem strategies, and market trends of six leading Layer 2 projects in the first half of 2025—Arbitrum, Base, Optimism, Starknet, ZKSync Era, and Linea. From Arbitrum’s push for permissionless verification to Starknet’s exploration of dual-chain settlements between Bitcoin and Ethereum; from Base’s innovations in privacy and speed to ZKSync’s development of resilient proof networks—these efforts not only shape the future of individual projects but also highlight the broader direction for overcoming blockchain’s scalability bottlenecks.

Arbitrum

Overview of Arbitrum

Arbitrum is a Layer 2 scaling solution for Ethereum, designed to tackle the challenges of slow transaction speeds and high fees on the Ethereum mainnet. It uses Optimistic Rollup technology to process transactions on Layer 2 and submit the results to Ethereum, ensuring security through fraud-proof mechanisms. Known for its high scalability, low fees, and seamless compatibility with Ethereum, Arbitrum leverages the security and ecosystem of the Ethereum mainnet. As of March 21, 2025, Arbitrum boasts a total value locked (TVL) of $2.52 billion, ranking second among the six projects discussed in this article.

Recent Highlights

Technological Developments

• BoLD Protocol for Permissionless Validation
  In February 2025, Arbitrum introduced the BoLD protocol, which enables anyone to become a validator and enhances the network’s security and decentralization.

• Stylus Sprint Initiative
  Arbitrum partnered with Trail of Bits to integrate Stylus into Meduza, enabling developers to conduct fuzz testing for Rust-based smart contracts and improving their audit capabilities.

• Major Network Upgrade
  Arbitrum announced an upgrade aimed at surpassing other EVM chains. To drive Rust-based innovation, 17 teams received 5 million ARB tokens.

Ecosystem Growth

• Leading in Stablecoin Integration
  Arbitrum upgraded its USDT to the USDT0 standard, setting a benchmark for Layer 2 platforms.

• AI Ecosystem Expansion
  On January 15, 2025, Aimagine was awarded Arbitrum’s AI Pioneer Grant. The grant aims to support projects that integrate professional AI agents and impactful on-chain AI solutions, helping to cultivate a thriving AI ecosystem within the Arbitrum network.
  On January 10, 2025, Arbitrum collaborated with Ai16zdao to leverage ELIZA in developing advanced AI applications on its platform.

• Uniswap v4 Launch
  On January 13, 2025, The launch of Uniswap v4 on Arbitrum offers users a faster and more efficient decentralized trading experience.

• Partnership with Rakuten
  On January 10, Rakuten chose Arbitrum to enhance its gaming and metaverse offerings, showcasing the platform’s growing appeal.

• Funding the ASS Project
  On January 2, 2025, the Arbitrum Foundation funded the ASS project to establish the first AI Agent Federal Reserve Bank—a fully autonomous, AI-driven financial infrastructure. This initiative marks the dawn of DeAI-Fi, a new era of decentralized AI-powered finance.

Tokenomics and Market Performance

• Token Unlock Plan
  In February 2025, Arbitrum plans to release 92.63 million ARB tokens into circulation. This significant token unlock could influence ARB’s market performance, prompting investors to stay vigilant and monitor market conditions closely.

• Token Buyback Plan
  To counter potential price drops, Arbitrum’s parent company initiated a strategic token buyback program. This effort aims to mitigate the impact of the upcoming token unlock and demonstrates the team’s confidence in the project’s long-term value.

ARB Price Analysis

As of March 21, 2025, ARB/USDT has been in a downward trend, with the price lingering around $0.37—a near one-year low. Despite notable developments earlier this year, such as partnerships with Trail of Bits, the launch of Uniswap v4, collaborations with Rakuten, and substantial investments in the AI ecosystem, weak capital inflows and selling pressure from ongoing token unlocks have kept prices under pressure.

From a technical standpoint, ARB is holding critical support at $0.35. A breach of this level could push prices down to $0.30. On the other hand, if the $0.35-$0.40 range forms a solid base with increased trading activity, a rebound could target resistance around $0.55. The persistent drop in trading volume reflects market hesitation, and future price movements will likely depend on the broader sentiment around BTC.

Source: https://www.gate.io/zh/trade/ARB_USDT

Base

Overview of Base

Base, launched by Coinbase, is a Layer 2 scaling solution for Ethereum that leverages Optimistic Rollup technology to tackle the challenges of high fees and low throughput on the Ethereum mainnet. Its goal is to provide a secure, cost-effective, and efficient blockchain platform for developers and users to build decentralized applications and foster on-chain economic ecosystems.

Ecosystem Growth and Developer Support

• Surge in On-Chain Activity
  The Base network has seen a surge in activity, with 11.4 million contracts deployed last week alone—a record-breaking milestone highlighting the high enthusiasm among developers and users.

• Building Essential Infrastructure
  On January 28, 2025, Venice was introduced as a key infrastructure component for AI agents, developers, and third-party applications on Base.

• Free Computing Power for Developers
  Aethir announced it would provide free GPU computing resources to developers working on AI projects within the Base ecosystem, significantly lowering barriers to entry for development.

• Future Vision
  On January 8, 2025, Base announced its plans to integrate into the “Superchain,” leveraging Ethereum to expand its ecosystem further.

Privacy and Security Enhancements

• Privacy Features Development
  On March 7, 2025, Base partnered with the @ironfishcrypto team to develop privacy features for on-chain transactions.

• Private Crypto Transactions
  On February 27, 2025, Base teamed up with veildotcash to allow verified users to send and receive cryptocurrencies privately, enhancing user privacy and security.

Performance Improvements

• Faster Transactions
  On February 28, 2025, Base achieved a technical breakthrough with Flashblocks, reducing block time from 2 seconds to 200 milliseconds. This advancement makes Base the fastest EVM-compatible chain, currently in testnet and expected to launch on the mainnet in Q2.

Innovations in Applications and User Experience

• On-Chain Film Streaming
  On March 5, 2025, Base introduced an on-chain Video on Demand (VOD) service, premiering the movie Cold Wallet to attract more users to blockchain technology through popular entertainment.

• Simplified Gas Payments
  On January 23, 2025, Base launched Circle Paymaster, enabling users to pay gas fees directly with USDC, making transactions more convenient.

2.2.5 Milestones in Transactions and Data

• Record Transaction Volume
  On January 24, 2025, Base became the second Layer 2 solution on the Uniswap protocol to surpass $100 billion in transaction volume, showcasing its vibrant ecosystem and strong market acceptance.

Optimism

Overview of Optimism

Optimism is a Layer 2 scaling solution for Ethereum that aims to solve scalability issues by increasing transaction throughput and lowering fees. It uses Optimistic Rollups technology to enhance Ethereum’s performance while preserving its security and decentralized nature.

Recent Developments

Strengthening the Ecosystem and Developer Support

• Cross-Chain Interoperability
  On February 22, 2025, Optimism launched the Superchain Interoperability Devnet and an ecosystem browser, paving the way for seamless cross-chain functionality.

• Improved Developer Tools
  On March 7, 2025, Optimism collaborated with Lambda Class to introduce the first development network built on the OP Stack, offering enhanced tools for developers.

• AI-Powered Documentation Assistance
  On January 23, 2025, Optimism unveiled the “Optimism Docs Assistant,” an AI tool designed to simplify navigation through official documentation, improving developer efficiency.

Decentralized Governance and Community Incentives

• Futarchy Governance Experiment
  From March 10 to June 12, 2025, Optimism and the Uniswap Foundation hosted the Futarchy Contest, which leverages prediction markets to refine decentralized governance. Participants can earn OP token rewards.

• Retroactive Funding Program
  From February 5 to July 31, 2025, Optimism launched the Retro Funding initiative, allocating 8 million OP tokens to reward contributors and builders advancing the Superchain ecosystem.

Ecosystem Growth

On February 12, 2025, Unichain joined the Superchain, becoming a new member and further expanding Optimism’s ecosystem.

Branding Refresh

On January 24, 2025, Optimism’s OP Mainnet introduced a new logo that aligns with its updated brand identity.

Source: https://x.com/Optimism

OP Price Trends

As of March 21, 2025, OP/USDT continues to show weakness, with the price hovering around $0.8781—near its lowest point in the past year. Although the Optimism ecosystem has progressed with mainnet upgrades and partnerships with on-chain protocols, market sentiment remains cautious, and selling pressure in the secondary market persists.

From a technical perspective, OP faces strong support at $0.83. If this level breaks, the price could drop further to the $0.75 range. On the other hand, if OP consolidates within the $0.83-$0.95 range and market conditions improve, a rebound may occur, with the first target set at $1.20. Recent trading volume has been declining, reflecting indecision among market participants. Investors should monitor capital flows and Bitcoin’s price movements for further insights.

Source: https://www.gate.io/zh/trade/OP_USDT

Starknet

Overview of Starknet

Starknet is a Layer 2 scaling solution built on Ethereum that uses ZK-Rollup (Zero-Knowledge Rollup) technology to address Ethereum’s high fees and scalability challenges. By generating STARK proofs, Starknet offers a high-throughput, low-cost, trustless blockchain environment, enabling developers to create complex decentralized applications. Utilizing the Cairo programming language, Starknet performs batch computations off-chain and verifies them on-chain using zero-knowledge proofs, significantly improving efficiency and security. Key features include high scalability, robust computational capabilities, on-chain data availability, strong security, and support for long-term decentralized development.

Recent Developments

Strategic Vision

• In 2025, Starknet aims to be the first Layer 2 solution to settle transactions on both Bitcoin and Ethereum, creating a unified layer for the two largest blockchain ecosystems. This integration could unlock new DeFi opportunities and liquidity.

Source: https://x.com/Starknet

• In 2025, Starknet aims to be the first Layer 2 solution to settle transactions on both Bitcoin and Ethereum, creating a unified layer for the two largest blockchain ecosystems.
• This integration could unlock new DeFi opportunities and liquidity.

Technical Updates

• v0.13.4 Version Release
  On February 27, 2025 (testnet launch), and March 17-24 (mainnet launch), Starknet rolled out Cairo-Native and Stateful Compression, reducing costs and improving transaction speeds.

Source: https://x.com/Starknet

• Cross-Chain Connectivity
  On March 12, 2025, Xverse Swap enabled cross-chain exchanges between Bitcoin and Starknet, enhancing interoperability.
  On February 14, 2025, Starknet announced the adoption of the IBC protocol, connecting over 100 blockchain networks.

• Improved User Experience
  On February 11, 2025, StarkGate bridge updated its interface for easier cross-chain operations.
  On January 31, 2025, tools developed by Endur and STRKfarm simplified the process of transferring assets from Ethereum and other chains to Starknet.

Staking and Decentralization Progress

• Upgraded Staking Mechanism
  On March 21, 2025, voting for STRK Staking v2 began, marking a new phase for staking on Starknet.

• Expanded Wallet Support
  Between February 17 and 20, 2025, STRK holders gained the ability to stake directly via the Keplr wallet and earn rewards. Nansen also integrated staking functionality with a points system for further incentives.

Source: https://x.com/Starknet

Ecosystem Incentives and Funding

• Regional Support Initiatives: On February 28, 2025, StarkWare launched a $4 million African startup fund to support Starknet’s ecosystem development in the region.

AI and Automation

• AI Agent Deployment Platform: On February 19, 2025, Kasar Labs introduced new tools enabling users to create and deploy AI agents on Starknet, fostering collaboration and enhancing automation within the ecosystem.

Data and Dashboard Tools

• Customizable Data Dashboards: On January 22, 2025, Starknet partnered with Token Terminal to allow users to build personalized data dashboards for Starknet analytics.

STRK Price Trends

As of March 21, 2025, STRK/USDT remains in a weak trend, with the price at $0.1671—a consolidation phase following a prolonged decline. Despite Starknet’s efforts to drive innovation and optimize on-chain performance, cautious market sentiment and insufficient capital inflows have limited price recovery.

Technically, STRK has support at $0.16. If this level fails, the price could test the $0.12 range. However, if support holds and trading volume increases, an oversold rebound may occur, with the first resistance target near $0.25. Current trading volume remains subdued, indicating hesitation among market participants. The future trend will depend on broader market conditions and Bitcoin’s price movements.

Source: https://www.gate.io/zh/trade/STRK_USDT

ZKsync Era

Overview of ZKsync Era

zkSync is an Ethereum-based Layer 2 scaling solution that leverages ZK-Rollup (Zero-Knowledge Rollup) technology to address high gas fees and slow transaction speeds on Ethereum. It provides a fast, secure, low-cost, and scalable blockchain environment for developers and users, enabling large-scale decentralized applications. zkSync uses zero-knowledge proofs and recursive proof techniques to batch transactions off-chain and submit validity proofs on-chain, significantly boosting efficiency. Key features include ultra-low fees, rapid confirmations, compatibility with Ethereum (supporting Solidity and Vyper), account abstraction, smart contract support, and strong scalability and decentralization.

Recent Developments

Technological Innovations

• EVM Bytecode Compatibility: Simplifies development by supporting EVM bytecode and advanced tools for developers.
• BoojumVM Enhancements: Strengthens zkSync’s security and scalability using BoojumVM technology.
• Elastic Network Development: Accelerates Elastic Network growth by offering documentation and tools for custom chains and seamless cross-chain operations.
• EigenLayer Collaboration: On March 18, 2025, zkSync partnered with EigenLayer to distribute ZK proof tasks to EigenLayer’s Active Validation Services (AVS), improving network security and resistance to censorship.
• Fermah Proof Generation Component: On March 18, 2025, zkSync introduced Fermah as a proof generation component, enhancing innovation in zero-knowledge proofs and improving scalability.

User Experience and Web3 Development

• Smart Login (SSO): Expected to launch in 2025, enabling seamless Web3 identity authentication and social recovery.
• Web2-Like Experience Goals: Aims to deliver a Web2-level user experience with 10,000 TPS performance and $0.0001 transaction costs while maintaining decentralized ordering.

Ecosystem Partnerships

• Graph Collaboration: On March 18, 2025, zkSync partnered with Graph to support zkSync Era subgraphs, providing decentralized blockchain data indexing for DApp growth.
• Gitcoin Pilot Program: On March 6, 2025, Gitcoin launched a six-month pilot program funded by the zkSync Foundation, offering 5 million ZK tokens as rewards for ecosystem contributors.
• Lens Chain Collaboration: On February 13, 2025, Lens Chain integrated with zkSync, using zkSync Shared Bridge for SocialFi gas payments.

Financial Collaborations

• UBS Partnership: On January 31, 2025, Switzerland’s largest bank UBS used zkSync for blockchain-based gold investments, offering enhanced privacy and convenience.

Security and Privacy

• TEE Updates: On January 14, 2025, zkSync updated its Trusted Execution Environment (TEE), combining TEE with zero-knowledge proofs to enhance security and trust.
• ZKSync Ignite: On January 6, 2025, zkSync Ignite Season 1 launched, planning to allocate 300 million ZK tokens over nine months to make zkSync Era a liquidity hub for resilient networks. However, due to poor market conditions, zkSync canceled its liquidity reward program “Ignite” on March 14.

Source: https://x.com/zksync

ZK Price Trends

As of March 21, 2025, ZK/USDT is trading at $0.07159, continuing a recent downward trend amid cautious market sentiment. After falling from its highs, the price consolidates at lower levels, with short-term support around $0.065. If this support is broken, the price could drop to $0.050.

Trading volume has been shrinking recently, reflecting weak market participation. However, if a surge in volume occurs, the price could rebound to the $0.10 range. Investors should closely monitor overall market sentiment and developments in the Layer 2 sector. For now, a wait-and-see approach is recommended until clearer trend signals emerge.

Source: https://www.gate.io/zh/trade/ZK_USDT

Linea

What is Linea?

Linea is a Layer 2 scaling solution compatible with Ethereum, designed to address network congestion and high fees by reducing transaction costs and increasing speed. Using Optimistic Rollup technology, it aggregates transaction data and submits it to the Ethereum mainnet, easing on-chain computational loads. Linea employs a data availability model called “AnyTrust” to enhance both security and scalability while maintaining full compatibility with the Ethereum ecosystem. Its key features include low transaction fees, support for smart contracts, compatibility with existing Ethereum tools, and strong support for decentralization and transparency. Linea aims to create a more efficient environment for decentralized applications.

The Future of Linea’s Decentralization

Source: https://x.com/LineaBuild

Recent Developments in Linea

Technological Advancements

• $LINEA Token Launch: The Linea Association plans to release the $LINEA token in Q1 2025 to enable community governance, allowing holders to participate in decision-making. However, as of March 26, no updates about the token launch had been announced due to weak market sentiment and liquidity challenges. Stay tuned to Linea’s official channels for updates.
• Seamless USDC Bridging: On March 26, 2025, Linea became the first blockchain to enable seamless conversion between USDC and native USDC, improving cross-chain interoperability.
• Enhanced Cryptographic Performance: On February 5, 2025, Linea optimized its Vortex polynomial commitment scheme using SWIFFT and Ring-SIS hash functions. By leveraging AVX512 optimization, it achieved Blake-level throughput (1,750Mb/s), significantly boosting cryptographic performance.

User Experience and Web3 Growth

• Decentralized Rewards Program: On February 27, 2025, Linea launched the world’s first decentralized, community-driven consumer rewards program. Users can earn 9% cashback through MetaMask Card purchases, with rewards available in DeFi tokens, stablecoins, memecoins, and NFTs.

Ecosystem Collaborations

• inch OG DEX Aggregator: On March 13, 2025, the inch OG DEX aggregator launched on Linea, enhancing decentralized trading capabilities.
• Foxy Cultural Token: On February 24, 2025, Linea introduced its first cultural token, Foxy, which became one of the ecosystem’s most popular communities.
• Sybil Attack Review: On February 17, 2025, Linea completed a review of Sybil attack appeals, updating false positive data and correcting 3.5k cases of misreporting.

Conclusion

The first half of 2025 has highlighted the vitality of Layer 2 solutions, driven by technological innovation and ecosystem expansion. From Arbitrum’s BoLD protocol advancing decentralized validation to Starknet’s ambition of bridging Bitcoin and Ethereum; from Base’s focus on privacy and speed to Optimism’s governance-driven community incentives; from zkSync’s collaboration with EigenLayer to enhance censorship resistance to Linea’s seamless USDC bridging—these projects are collectively shaping the future of Layer 2 with unique approaches.

While the market faces short-term pressures from token unlocks and liquidity challenges, projects are building long-term value through technological upgrades, ecosystem incentives, and strategic partnerships. Innovations in AI agents, on-chain privacy, and high-performance consensus address blockchain’s “impossible trilemma” and signal Layer 2’s transformation from a scaling tool to foundational Web3 infrastructure. As cross-chain interoperability improves and decentralized governance matures, Layer 2 could become the key hub connecting multi-chain ecosystems and supporting billions of users, paving the way for explosive growth in DeFi, SocialFi, GameFi, and beyond. The second half of this evolution may witness Layer 2’s historic leap from a “performance patch” to a “value engine.”