Nethereum is an open source .NET integration library for Ethereum. It is designed to help developers easily integrate the Ethereum blockchain into their .NET applications. It consists of modular libraries for features that are covered are writing smart contracts, cryptographic wallets, DApps, and managing blockchain data.

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.

NEO, formerly known as AntShares, is one of the leading smart contract enabled blockchain platforms that allows for the development of digital assets. Similar to Ethereum, NEO uses two different tokens: NEO and GAS, each of which have a specific purpose on the network. NEO tokens give holders a share in the ownership of the NEO blockchain, and when they are held in a compatible wallet, they are rewarded with GAS tokens. NEO has a Delegated Byzantine Fault Tolerance (dBFT) consensus algorithm that has uses some features of PoS, and is designed to be more scalable than other consensus mechanisms.