Fantom is developing a smart contract platform based on a directed acyclic graph (DAG). They hope to address the scalability issues of current decentralized platforms. Instead of a blockchain, Fantom's Lachesis Protocol uses a directed acyclic graph to confirm transactions asynchronously. This transaction history is immutable and cannot be modified. The platform's Opera Chain will consist of three layers: an application Layer, Opera Ware Layer, and Opera Core Layer. Fanotm issued an Ethereum-based token in 2018.

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.