Sharded PoS is now a reality

24 months ago the Harmony protocol was nothing more than a whitepaper and a promise. Now that promise is a reality.

On Saturday, May 16 at block 3375104, the mainnet entered its first staking epoch and in so doing, claimed a little piece of history as the very first sharded PoS public network.

This means, you can now freely and openly participate in Harmony’s decentralized economy. And you should start now because the sooner you stake, the more you’ll earn. Annual staking rewards are currently hitting 100% in some cases, but those rates won’t last long.

Head over to our staking dashboard at Make sure your tokens are stored in a compatible wallet i.e. Ledger, Math, or Harmony browser extension. Delegate to any validator you like the look of. Collect rewards. And repeat.

If you’re clever, you can earn even higher rewards. Our Effective Proof-of-Stake mechanism designed by CTO RJ Lan gamifies the staking process and rewards those savvy enough to play the game to their advantage.

Learn all about Effective Proof-of-Stake

Transcending the trilemma

So what’s the secret sauce behind Harmony? Fundamentally we set out to solve the famous blockchain trilemma:

Security, scalability and decentralization.

Conventional wisdom says pick two, you can’t have all three. Well now you can. Many projects have successfully launched high throughput networks with impressive TPS but we find the sacrifices in other areas detract from their value as truly decentralized blockchains. These are not sacrifices we were prepared to make.

The combination of proof-of-stake and sharding emerged as the leading solution for blockchain scaling in 2018. In theory it could increase throughput and reduce cost while preserving security and decentralization. As we know, however, theory is fine… in theory.

Sharding: complexity upon complexity

So why are sharding and staking so hard to bring together?

Firstly, staking is still very much a frontier technology within blockchain. It has taken other projects years to design and implement a secure staking protocol for a non-sharded chain. But when we add sharding (another frontier technology) into the mix the complexity increases dramatically.

Staking must be coordinated globally across the entire network yet each shard must also run their own PoS consensus individually. So each shard relays information back and forth to a beacon shard to coordinate basics such as voting power, slashing and rewards. Maintaining rock solid cross-shard communication while preserving security requires enormous theoretical rigor and practical engineering.

And no, this hasn’t been easy. It’s taken a herculean effort from engineers and our community to get us here. We’ve spent countless late nights fixing bugs, repelling attacks and recovering shards. These are problems nobody’s had to solve before and as an open source project we’re actively building the playbook for sharded blockchain architecture.

The path to full decentralization

Open Staking is a major step towards full decentralization of the Harmony network. The more decentralized we become the better we can serve our mission of scaling trust for billions of people. The launch of Open Staking is about the transition from a small community of foundational nodes to hundreds (and eventually thousands) of validators around the world.

Where next?

This is blockchain. Milestones come and go but value endures. And now is the time for us to create meaningful value, leverage the powerful architecture we have built and tackle the greatest challenge of all: adoption.

It might appear that we’ve been quieter than some other projects but, following the many high-profile hacks seen this year we decided to prioritise security, iron-clad execution and stability over announcements. A fledgling network cannot afford mishaps. Now, equipped with a battle-tested base layer, we will shift gears to pursue adoption with the same nonstop execution that took us from whitepaper to mainnet in little over a year. Our scalability, speed and cost will fuel the development of use cases and user experiences that would have been unthinkable just a few years ago.

Our long-term vision remains tackling the rapidly-growing problem of Trust. Our near-term goal, cross-border finance, presents the problem of Financial Trust — in other words, certainty that the other side will honour their side of a transaction. With Harmony’s settlement time of 8 seconds, it is an ideal and highly scalable use-case for our technology. We see India, in particular, as an exciting market for development and grants are available to fund teams eager to build on our network. If you’re keen to get your hands dirty and build the future with us, please get in touch.

On the technical side we’ve achieved a significant milestone, but we’re not stopping here. Not even close. We are committed to deliver on our early promise of deep sharding by going beyond the consensus layer down into the networking stack to optimize performance. Hot on the heels of this release will be another mainnet upgrade featuring significant improvements to our P2P layer. This upgrade will reduce our time to finality below our current 8 seconds and it will safeguard against P2P attacks. These upgrades are already complete and ready for testing and will be shipped in the coming months.

Real-time demo of Harmony’s transaction speed

Credit where credit is due

To the foundational nodes and the P-OPS (our Pangaea Captains) who went above and beyond again and again supporting our development over the last year, we owe you a huge debt of gratitude. You have been with us every step of the way and your commitment to maintaining uptime has been inspiring. We could not have done this without you.

To our community who stuck with us in the belief we would deliver on the promise of the whitepaper, we know it’s been tough and we’re grateful for your encouragement and your input over the last 12 months.

But the largest thanks must go to our engineers who have worked long into the night, week after week, month after month, testing and refining the code, spinning up networks, all while adjusting to the unexpected demands of remote work. They are unsung heroes but the sinequanon of Harmony.


Decentralization is a process, not a button you can simply push and be done. We’ve accomplished a lot but there are still many milestones ahead. With staking launched the day to day now becomes a process of constant growth for everyone.

We now turn our sights to attracting the world’s best developer talent, winning over sceptics and finally realising the promise of this exciting technology.

-Robin Schmidt, Creative Director, Harmony