Alys is a Bitcoin Layer 2 solution focused on DeFi applications, leveraging BitVM for an EVM-compatible execution environment secured by Bitcoin.

Arch Network is a Bitcoin Layer 2 scaling solution enabling Turing-complete smart contracts on Bitcoin's base layer using ArchVM and a decentralized verifier network with FROST + ROAST signatures. It supports trustless DeFi applications without bridging, preserving Bitcoin's liquidity and security.

Ark is a Bitcoin Layer 2 protocol designed to scale transactions through a shared UTXO model, enabling fast, low-cost, and private off-chain payments. Utilizing virtual UTXOs (vTXOs) and Ark Service Providers (ASPs), Ark simplifies liquidity management by eliminating the need for payment channel setup, unlike the Lightning Network. Recent developments include Virtual Channels for off-chain contracts and Taproot Assets integration, enhancing BTCfi applications. Ark supports trustless, unilateral on-chain redemption, ensuring user control over funds.

Ark Liquid combines the Ark Layer 2 protocol with assets on the Liquid Network sidechain, enabling scalable, confidential off-chain payments with Liquid's infrastructure.

B² Network is a Bitcoin Layer 2 using ZK-Rollup technology with Bitcoin L1 verification, offering EVM compatibility and enhanced scalability.

BEVM is an EVM-compatible Bitcoin Layer 2 sidechain using Schnorr signatures and MAST from Taproot to manage BTC bridging for smart contracts.

Bison Labs develops a Bitcoin Layer 2 using sovereign ZK-Rollups, enhancing scalability for DeFi with zero-knowledge proofs.

Bitfinity is an EVM-compatible Bitcoin Layer 2 sidechain on the Internet Computer (ICP), enabling faster, cheaper transactions and Ethereum dApps.

Bitlayer is a Bitcoin Layer 2 solution using BitVM, enhancing scalability and enabling complex applications with Bitcoin’s security.

BOB (Build on Bitcoin) is a hybrid Layer 2 combining Bitcoin’s security with Ethereum’s EVM compatibility, enabling dApps with Bitcoin settlement.

Botanix Labs’ Spiderchain is a decentralized, EVM-equivalent Bitcoin Layer 2 sidechain using multi-signature wallets managed by distributed participants.

BounceBit is a Layer 1 blockchain secured by staking Bitcoin and its BB token, enabling BTC restaking for CeFi and DeFi yield.

BRC-20 is a token standard using Ordinals inscriptions to create fungible tokens on Bitcoin’s mainnet, scaling tokenization use cases.

Citrea is Bitcoin’s first ZK-Rollup Layer 2, enhancing scalability by verifying state transitions on Bitcoin L1 using BitVM-inspired zero-knowledge proofs. EVM-compatible, it enables smart contracts for DeFi, gaming, and NFTs, leveraging Bitcoin’s security.

Ethereum is a leading blockchain supporting Bitcoin scaling through wrapped BTC tokens like WBTC and cbBTC, enabling fast, low-cost DeFi and dApp integrations on its Layer 1 and Layer 2 networks. Recent upgrades like Pectra and L2 solutions such as Arbitrum and Scroll enhance throughput and user experience.

Hedgehog is an early-stage Bitcoin Layer 2 proposal using state channels to enable scalable, off-chain transactions.

Hemi is a Bitcoin Layer 2 sidechain with EVM compatibility and Bitcoin L1 finality, providing a platform for DeFi applications.

Libre Chain is a Layer 1 blockchain designed for Bitcoin DeFi, with fast transactions and EVM compatibility, bridging Bitcoin via delegated PoS.

Lightning Network is a decentralized Layer 2 payment protocol on Bitcoin, enabling near-instant, low-fee transactions via bidirectional payment channels.

Liquid Network is a Bitcoin sidechain by Blockstream, enabling faster, confidential transactions and digital asset issuance for traders and exchanges.

Lumibit is a decentralized Bitcoin Layer 2 network using ZK-Rollups, enhancing scalability and supporting diverse applications.

Mantle Network is an EVM-compatible Layer 2 rollup on Ethereum, enabling Bitcoin scaling through wrapped BTC tokens like Ignition FBTC and PumpBTC. It uses optimistic rollups with a modular architecture, leveraging EigenDA for decentralized data availability to achieve high throughput, low-cost transactions, and seamless DeFi integration.

Mercury Layer is a Layer 2 statechain protocol for Bitcoin, enabling private, scalable off-chain BTC transfers via semi-trusted Statechain Entities.

Merlin Chain is an EVM-compatible Bitcoin Layer 2 with ZK-Rollup technology, decentralized oracles, and on-chain BTC fraud proofs, empowering native assets.

Mezo is a Bitcoin Layer 2 sidechain by Thesis, using Proof-of-HODL consensus and trust-minimized BTC bridges to secure the network and earn yield.

Nomic is a Layer 1 blockchain using Cosmos SDK, functioning as a non-custodial Bitcoin bridge, enabling BTC transfers to Cosmos chains as nBTC.

Ordinals, launched in 2023, enable NFT-like inscriptions on Bitcoin’s mainnet by embedding data in transaction witnesses, scaling use cases for digital artifacts.

RGB is a smart contract system for Bitcoin and Lightning Network, using client-side validation for scalable, private off-chain transactions.

RIF provides decentralized infrastructure protocols and services on the Rootstock (RSK) sidechain, enabling dApp development with Bitcoin security.

Rollux is an EVM-compatible Optimistic Rollup Layer 2 by Syscoin, benefiting from Syscoin’s Bitcoin merge-mined Layer 1.

Rootstock (RSK) is a Bitcoin sidechain enabling EVM-compatible smart contracts, secured by Bitcoin’s hash power through merge-mining and a 2-way Powpeg.

Runes, introduced in 2024, is a protocol for issuing fungible tokens on Bitcoin’s mainnet using UTXO-based inscriptions, simplifying token creation.

SatoshiVM is a decentralized Bitcoin ZK-Rollup Layer 2 compatible with EVM, using native BTC as gas.

Schnorr Signatures, activated with Taproot in November 2021, enhance Bitcoin’s efficiency and privacy by enabling signature aggregation and complex scripts.

SegWit, activated in August 2017, restructures Bitcoin transaction data to increase block capacity, fix transaction malleability, and enable Layer 2 solutions like Lightning.

Solana is a high-performance blockchain supporting Bitcoin scaling through wrapped BTC tokens, enabling fast, low-cost DeFi and dApp integrations.

Sonic is a Bitcoin Layer 2 using rollups, aimed at enhancing scalability for applications like gaming within the Bitcoin ecosystem.

Stacks is a Bitcoin Layer 2 enabling smart contracts and dApps, secured by Bitcoin’s Proof-of-Work via Proof-of-Transfer (PoX) consensus. The recent Nakamoto upgrade has introduced trustless sBTC peg-out and improved security against chain reorganizations.

Taproot, activated in November 2021, introduces Schnorr signatures, P2TR outputs, and Tapscript, enhancing Bitcoin’s privacy, efficiency, and smart contract capabilities.

Tuna Chain is a hybrid Bitcoin Layer 2 combining ZK-Rollup and Optimistic Rollup elements, focusing on fast, low-cost DeFi applications.

Zulu Network is a two-layered Bitcoin Layer 2 sidechain; ZuluPrime is EVM-compatible using BitVM, and ZuluNexus integrates UTXO-based chains.