Blockchain startup RSK Labs Ltd has raised $1 million to further develop Rootstock – operator of a future smart contract platform.

The round was led by bitcoin hardware mining producer, Bitmain Technology, which was supported by Digital Currency Group (DCG), seed investor from New York, and Coinsilium, blockchain investment firm. The funding will reportedly be used for technical needs.

Rootstock is designed as a sidechain operating on the bitcoin blockchain that is expected to expand its functionality with smart contacts. The launch of the platform’s beta testnet is scheduled for September 2016, with a private testnet set at the end of April.

Although some critics point to similarities between Rootstock and Ethereum concepts, the fundamental difference lies in the fact that Ethereum uses its own blockchain while Rootstock builds its services around the bitcoin ecosystem. Besides, Rootstock is elaborated as a sidechain and thus can raise interoperability between Bitcoin and Ethereum blockchains – the two most successful blockchain platforms as of now. According to the blog post describing the platform’s concept, Rootstock is not planning to issue a new currency. Instead, it will provide a two-way peg between bitcoin and the native Rootstock token called RTC, which can be easily converted. Blog post sums up the idea of Rootstock project in the following way: “What RSK is offering is Bitcoin-like security with Ethereum-like flexibility.”

The platform’s developers expect to boost bitcoin ecosystem, the value of the network and bitcoin itself as the currency. As Diego Gutierrez Zaldivar, RSK Labs Ltd CEO, explained in an interview, Rootstock hopes to gain support from bitcoin miners since it will reportedly enable them to collect transaction fees on RSK contracts as well.

This is not the first time that Coinsilium invests in Rootstock. In January 2016, this London-based investment and development company, which supports early-stage blockchain startups, invested $100,000 in RSK Labs Ltd.

Anna Lavinskaya