Bitcoin's long wait for the Lightning Network is almost over.
Announced today, the startups behind the three most active Lightning implementations have revealed test results, including live transactions, proving their software is now interoperable.
The findings, released by ACINQ, Blockstream and Lightning Labs, effectively bring Lightning (the mechanism many see as the best solution for increasing bitcoin's capacity) closer to public launch.
And while admittedly technical, today's announcement offers evidence that makes it seem like enthusiasts will soon get their wish.
Firstly, the Lightning specifications, in progress since last September, have entered version 1. These describe the rules of the network, comparable to the standards that prop up the internet.
While that's not to say the specifications won't evolve over time, they've now been deemed good enough to support the first real Lightning Network.
According to the founder of ACINQ, Pierre-Marie Padiou:
"This is the Lightning standard we've been working on for more than year. There's been a lot of work from us and from all participants. It's a big milestone."
Secondly, all the implementations have been shown to be compatible with one another, based on Blockstream engineer Christian Decker's over 70 tests, which he put together over the summer.
And last, but not least, as displayed with the two live transactions, the three main implementations of Lightning are indeed interoperable, a piece of the puzzle that developers have been working on since last year.
"We've been able to make successful payments on the mainnet that goes all around the world, and which involves different compatible implementations," Padiou said. "That's kind of a big deal."
Interoperable, at last
While Lightning is still not ready for public use, Padiou emphasized that interoperability between the implementations is key to continuing development.
With the specifications complete, other developers now know what rules to implement to build their own Lightning networks. Bitcoin startup Blockchain's Thunder Network and MIT's Lit, for example, are two other well-known Lightning projects that could one day also implement the specifications.
And this compatibility between implementations has now been demonstrated with two test transactions, showing how Lightning could be used in the future for small value payments.
One transaction was routed through Blockstream's C-Lightning nodes to ACINQ's fake coffee app Starblocks (a play on Starbucks), which sells "Blockaccinos" for 0.015 mBTC.
The other transaction unlocked a blog post on the content platform Yalls. The process used ACINQ's Eclair wallet to send a tiny fee through C-Lightning to Yalls, which runs on Lightning Lab's LND software.
The engineers conducted both of these Lightning payments with nodes scattered across the globe, Padiou said.
"It's a very small network, but it demonstrates how the interoperability works," Padiou said, adding that this highlights a live proof-of-concept for the scaling mechanism.
No rush
But there's still one more step before users can take advantage of Lightning: releasing mainnet software.
According to Padiou, each implementation needs to release beta software for the mainnet that allows bitcoin users to make real payments over the Lightning Network for the first time.
And while many are excited about the opportunity, that software will need plenty of work before the dream of paying for morning lattes (and everything else) using bitcoin is realized.
In conversation, Lightning developers stressed there are kinks left to work out with the user experience before they recommend businesses adopt it.
Padiou argued that this cautious approach to development shows developers are making sure they get the technology just right, so as to eliminate the chance of users losing funds.
"It also demonstrates the approach has been very conservative. We're not going to rush anything," he told CoinDesk, adding: