Chain today is launching as a startup that hopes to become the definitive development platform for Bitcoin, whether the ultimate application relates to financial services or to some other sort of decentralized service.

It also will announce $9.5 million in Series A funding. Khosla Ventures led the round, and was joined by RRE Ventures, Thrive Capital, SV Angel, Box Group Kevin Ryan, Barry Silbert, Scott Banister, Homebrew, 500 Startups and Pantera Capital.

“Our thesis is that we’re in an era where people are looking for services to simplify very technical infrastructure so that they can build on-demand services,” explains Adam Ludwin, Chain’s founder and a venture partner with RRE Ventures. “The blockchain is this mammoth network that is quite difficult to build on…. It’s like telecom or credit card processing or web hosting where certain people at the beginning tend to do it themselves but, over time, it matures and bigger companies start accessing it. So what you need is reliability and real service-level agreements. When a big bank wants to connect to the blockchain, they want an expert to help them. We want that to be us.”

Ludwin and his team originally raised seed capital nine months ago for a consumer-facing startup — including from some of the aforementioned investors — but soon became more interested in what ultimately became Chain. It still had around $2 million in the bank before closing the Series A round in late July.

Keith Rabois, a partner with Khosla Ventures and the former COO of Square, will join Chain’s board as part of the deal. It’s also worth noting that Rabois sits on the board of Stripe, which has created an online payment method called Stellar which some see as a Bitcoin competitor. Rabois, however, argues that the two can peacefully coexist, as Stellar users can transact with Bitcoin.

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