æternity is a public, open-source blockchain protocol that enables a platform for next-generation decentralized applications with high scalability. Its core components are written in the functional programming language Erlang and its smart contract language - Sophia - is also functional. æternity has a stellar team of developers including Robert Virding - co-creator of Erlang, John Hughes - co-designer of Haskell, and Ulf Norell - co-designer of the Agda programming language for formal verification. Unlike other blockchain platforms, the æternity protocol itself incorporates a number of essential technological features. State channels for off-chain scaling, oracles for real-world information, and a naming system for increased user-friendliness are all implemented on Layer 1. æternity also features SDKs in Javascript, GO, Phyton, Java, as well as a middleware and a development suite that streamline smart contract development. æternity incorporates the Bitcoin-NG consensus algorithm developed by academics from Cornell University and uses the Cuckoo Cycle mining algorithm for Sybil attack protection. AE tokens, the native cryptocurrency of the æternity platform, is used for both - an economic unit of account and as ballots in the community-driven on-chain governance votes.
Grin coin is a private & lightweight open source project based on the mimblewimble blockchain implementation. MimbleWimble is a lightweight blockchain protocol proposed by anonymous author that goes by the name Tom Elvis Jedusor (inspired by Harry Potter) in July 2016. Since then, the proposal has gained a huge following among Bitcoin and privacy advocates. Unlike bitcoin or ethereum, there are no addresses in Grin. In order to transact using Grin, both wallets must communicate with each other online with the results broadcasted to the network. Another key different is that transaction history (sender, receiver, amount) will not be recorded on the blockchain. Due to the removal of these information from the transaction, the data size remains small and that keeps the blockchain lightweight. New nodes can easily join the network without having to download a large blockchain. Grin coin was launched without an ICO, fundraising, or pre-mine. Developers around the world contribute openly with the goal to ensure the coin distribution remains as fair as possible. There are 2 popular wallets widely available to interact with the Grin network. Grin core wallet: https://www.coingecko.com/buzz/how-to-use-grin-wallet-to-send-receive-grin-coins Wallet713: https://www.coingecko.com/buzz/how-to-use-grin-wallet713-to-send-and-receive-grin-coin-step-by-step-guide The consensus algorithm used by Grin is the Cuckoo Cycle proof-of-work based. There are 2 hashing algorithms involved with Grin. Cuckoo-29 is meant for GPU mining while Cuckoo-31 is meant fo ASIC mining. This is a deliberate design to encourage miners to eventually move into ASIC mining for efficiency while keeping it fair at the beginning of the launch. Grin coin has launched its mainnet on 15th January 2019 and is now available for mining and trading.