After Exceeding 10k TPS in Testnet, Elrond Is Going Open Source

Beniamin Mincu
Elrond Network
Published in
5 min readJun 21, 2019


When Elrond was founded at the end of 2017, we set out to build the first truly scalable blockchain architecture. One that could bring a 1000x improvement in throughput and execution speed. If we could deliver, it was clear this contribution would significantly change the space, much like how the internet changed when it transitioned from dial-up to broadband. Within the span of 1.5 years in which we’ve been working on solving this problem, the perception of our solution has shifted from crazy, to bold, and now to very obvious.

For some context, we were the first to fully formalize a state sharded proof of stake architecture, and presented our paper in May 2018. We were also the first team to validate our hypothesis, demonstrating we could do cross-shard transactions in July 2018. We’ve open sourced the prototype in November, rewrote everything from scratch for our testnet, and achieved a 30x improvement in performance compared to the prototype. This path seems like a simple straight line in retrospect, but it was one hell of a ride in terms of effort, difficulty, risk and accomplishment.

Today marks another significant leap forward for Elrond, so here it is.

Technical paper update

We are so excited to release Version 2.1 of Elrond’s technical whitepaper with significant updates. Ever since we released our first whitepaper version, we have been constantly researching and implementing new state-of-the-art solutions. The second version was released back in November 2018. As we are designing and writing our architecture from the ground up, we are constantly improving it and the algorithms throughout the protocol.

The most significant updates in the whitepaper are the following:

  • Metachain notarization and synchronization scheme
  • Cross-shard transaction handling
  • Smart contract processing on a fully sharded architecture (network, transaction, state)
  • Consensus optimization: reducing communication rounds from 5 to 2, communication complexity from O(N²) to O(N) by changing from Belare-Neven to BLS-multisignature
  • New randomness beacon through BLS single signature scheme
  • Security enhancement through: “K” block finality scheme and fisherman challenge

Testnet release, status and results

Another important milestone is the release of our testnet with the blockchain explorer and the wallet. The latest version is online since last Friday — 14.06.2019 — and it already committed more than 100K blocks per shard and processed more than 100 million transactions. All of this is running on 126 AWS nodes from different geo locations using only T2.Medium machines — dual-core processor with 4GB of RAM. The current set-up is producing a block every 6 seconds with both intra and cross-shard transactions enabled. The peak TPS achieved with only 5 shards is 11.966 TPS — theoretical maximum being 12.500 TPS.

Most projects are speaking only about peak TPS, but metrics like average TPS, time to finality, percentage of cross-shard transactions and hit rate (percentage of rounds where a block was proposed after consensus) are almost never mentioned. The average TPS is strongly impacted by the hit rate: a hit rate of 50% (in just 50% of the rounds consensus is reached and a block is proposed) severely limits the throughput to just 50% of the theoretical max limit. By optimizing both our peak TPS and consensus hit rate we reach very high average TPS. The hit rate of the testnet at the moment of writing is 99.7%.

But don’t just take our word for it, you can try things for yourself: check the testnet, create a new wallet, claim some testnet tokens, and send them to your friends. Nothing drives the point home better than a first hand experience.

What is not available but will come soon: Validator nodes cannot be run outside of our environment yet, but this is also coming. The good part is you can still connect as an observer node, monitor the network and watch how the chain of blocks is built in real-time.

One more thing…Elrond goes open source!

Blockchain technology is termed as the fifth evolution of computing. The best way of accelerating innovation in a changing world, is to open source it. Open-source is a faster way to learn, build, take feedback, collaborate, and build a community around a product. Passionate development teams that span across the world can unlock invaluable resources and take products to the next level.

Why now? We are entrepreneurs, engineers and researchers, so what we release must meet certain quality standards. Specifically, we wanted to distribute the code only after having the two key pillars of Elrond’s architecture implemented and tested: state sharding and secure proof of stake. We wanted ensure that what we launch is stable enough, and while there are still some known bugs in the system — you are more than welcome to help track and fix them. In the last months we have continuously stress tested the protocol, produced millions of blocks, processed billions of transactions — everything on real setups, multiple machines deployed and scattered throughout almost every continent on earth.

Now after more than 150K lines of code (only for the protocol) and more than 1000 commits, we are excited to share some of our secrets with the world — a truly scalable and fast decentralized blockchain platform.

The list of implemented modules is long, but we will share a few key points:

Stay hungry, stay foolish

As we begin this new phase, it’s worth taking a moment to reflect on what brought us here in the first place. We’ve started with a vision we all shared as a team, and put an insane amount of effort to execute on it. While reinventing our architecture, we’ve been reinventing ourselves as well. We’ve built a team with which we could build rockets — but perhaps an even more important accomplishment is the strong bond and fellowship among our team. You can always copy technology, but with this team we can reinvent technology, and will move mountains to see it through and bring it to the market.

So what’s next? As we prepare to announce more info on the “Battle of Stakes” and open source the Elrond VM in 1–2 weeks, you can join our riot channel, contribute to our early documentation, run some nodes, play with the explorer and the wallet, and if you feel really adventurous, come contribute to the Elrond Github. It’s still early days for Elrond, but things keep improving really fast.

Whether you’re a hungry developer or curious researcher, this is your chance to join the Elrond fellowship, help build this nascent technology, and put it to good use.

What are you waiting for? 🤔

About Elrond

Elrond is built by a team of experienced entrepreneurs along with 13 engineers and researchers with significant technical experience at Microsoft, Google, Intel, NTT DATA, 2 PhDs in CS & AI, multiple math, CS and AI olympiad champions, and blockchain backgrounds, including being previously part of the NEM core team.

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