Ethereum is stuck between a rock and a hard place. The rock is its overwhelming popularity—94 of the top 100 currencies use Ethereum to make ends meet. And the hard place is the difficulty in upgrading the network to increase transaction speeds and lower transaction costs. That's led to usurpers such as EOS, Cardano and NEO to pick off developers desperate for a network that can work. Some have even gone so far as to declare the king is dead.

While there have been several solutions put forward to fix the problem: Casper, Sharding, Plasma, Raiden Network—they've all run into roadblocks. (Here's a good round up of why.) Now Vitalik Buterin, Ethereum's reluctant king, has set the next stage of its planned evolution: Serenity.

“Serenity is the world computer as it's really meant to be. Not a smart phone from 1999 that can process 15 transactions per second and maybe, potentially play Snake.”Vitalik Buterin

Buterin told attendees of DevCon 4 today that after trying and abandoning various proof-of-stake ideas over the past few year—including a betting method for selecting new blocks as well as dealing with the DAO hack and the Shanghai DOS attacks—Ethereum is finally ready for the next step. That's where Serenity comes in, which he described as a hybrid proof-of-stake consensus mechanism that will finally allow a scalable proof-of-stake blockchain.

“It is a realization of all of these different strands of research that we’ve been spending our time on for the past four years. This includes Casper—not just hybrid Casper, 100% organic, genuine, pure Casper,” Buterin told the assembly.

The changes are so severe that it will a require an entirely new blockchain, with a backlink to the existing proof-of-work chain. The long-term goal is that once the system is stable enough, all the applications on the existing blockchain will be folded onto a shard on the new chain. This means the new chain will be fully compatible with the old one while enabling it to scale.

The blockchain will also be a smaller size, meaning validators don't need massive amounts of storage to be able to run a full node. Buterin expects the storage requirements to be under 1 Gb, compared to 8 Gb as it is today, “not the 1.8 Terabytes trolls on the internet think the blockchain requires for some stupid reason,” he quipped.

One challenge for mainstream adoption of blockchain is that confirmation times, which sometimes can take hours. Buterin promised the new model will fix all that. Because it is synchronous, one confirmation will mean the transaction has been included by not just one validator, but hundreds. This could allow coffee shops or other businesses to safely accept Ethereum in under 16 seconds. At least, that's the goal.

But we've heard these kinds of promises before from Buterin. Ethereum is under pressure to make this fix stick, otherwise its first-mover advantage is in danger of being washed away.