Cardstack is a blockchain technology company that is developing an open-source framework and consensus protocol to make blockchains more usable and scalable. Their goal is to create a decentralized modular smart contract ecosystem. The Cardstack network is powered by the Ethereum-based CARD token.

Harmony is developing an open consensus blockchain platform. Harmony's sharding-based consensus mechanism is designed to scale as the number of nodes increases in the network. Harmony aims to tackle issues related to scalability by optimizing across multiple layers in a way that will enable parallel transaction processing with reduced latency. Harmony is currently powered by the ONE token, which is built on the Binance blockchain.

Parity Technologies is an influential blockchain development company that offers a variety of open-source software solutions for creating and using decentralized technologies. Some of their solutions include Ethereum and Bitcoin clients, cross-chain technologies, smart contracts, testnets, and cryptocurrency wallets. The company was created by Gavin Wood, the co-founder of Ethereum.