The Matic Network is a sidechain based scaling solution for public blockchains. Matic aims to allow developers to better scale their Ethereum DApps by using a version of Plasma, along with side chains that use a PoS consensus mechanism. Matic plans on supporting other blockchains as well in order to facilitate interoperability.

Ignis is a blockchain platform that is being developed by Jeluirda; the company behind Ardor and Nxt. Ignis is a child chain of the Nxt blockchain. Jelurida is developing blockchain platforms that will enable users to develop decentralized applications, and will be based on a parent and child chain architecture.
Ignis allows users to create child chains with specific features and to create tokens that meet their needs. This project is closely related to Ardor and Nxt.

NULS is creating a blockchain coding environment that will be easy to use. NULS wants to make a blockchain development platform that will offer a solution for developing decentralized applications, at a lower cost and with less technical knowledge. The company has teams working in several countries and the platform is powered by the NULS token.
NULLS uses modular smart contracts that are flexible and can be customized for business needs. NULLS provides a coding environment where developers can utilize multi-chain mechanisms, cross-chain consensus, and other technical blockchain features with less technical knowledge.