Polygon Co-founder Anurag Arjun on Why Ethereum Needs Layer 3s

Key Takeaways

• In an interview with CCN, Polygon alumnus Anurag Arjun discussed Ethereum rollups and an emerging Layer 3 infrastructure.
• Arjun’s latest project, Avail, has spun off from Polygon to produce a data availability solution for L3 rollups.
• He said that L3s can dramatically reduce the cost and effort needed to build customized, application-specific chains. 

In the early years of Ethereum, different approaches to scaling the platform’s capacity vied for developers’ attention, including Plasma chains, state channels and rollups. These days, however, while interest in Plasma and state channels hasn’t completely disappeared, the most successful scaling solutions are rollup-based Layer 2 (L2) networks.

Among the architects of the L2 revolution, ex-Polygon co-founder Anurag Arjun  helped build one of the first Zero-Knowlege rollups, Polygon zkEVM. In an interview with CCN, Arjun explained that for his next project, he is looking ahead to Ethereum’s third infrastructure layer. 

Rollups on Rollups:  What are Ethereum L3s?

Anticipating a future in which L2 rollups support a host of application-specific “L3” chains, Arjun has departed from Polygon Labs, spinning off a new “rollup agnostic” scaling technology known as Avail .

While L2s have significantly scaled Ethereum’s throughput, they are still vulnerable to congestion, he observed. In contrast, “if you look at the internet and how internet apps really scaled, each application writes their own business logic and handles their state in their own data store”.  

Expanding on the analogy, he noted that Web2 developers:

“They don’t go and say, ‘I want to go on this big supercomputer and deploy my app there.’ They write their app in the datastore and deploy it to their own [virtual machine] on the cloud… It’s very neatly segmented and it’s not the case that if there’s heavy usage on Amazon it will cripple a startup’s app.”

According to Arjun, Ethereum L3s will introduce a similar scheme for Web3 decentralized applications (DApps). 

Rather than the current model, where a surge in activity on one application can spike fees for all users of the same rollup, he anticipates DApps evolving into independent “appchains” – each one rolling up data and publishing to the L2 according to its own internal logic. 

How Appchains Benefit Web3 Developers

Because they are designed to operate as application-specific blockchains, L3s are often referred to as appchains. However, Arjun acknowledged that this could generate confusion with technologies like Cosmos. 

Referring to Starknet’s take on the concept, which is deploying Avail as an L3 data availability solution, he noted that “they take the name of appchains, but essentially, what you’re creating is an app rollup.

Cosmos Appchains vs. Starknet’s L3 Evolution

The key difference between Cosmos appchains and Starknet’s emerging L3 infrastructure, he continued, is that the former are fully sovereign blockchains, each one requiring its own token system and validator set.

In contrast, “if you build a rollup, you don’t have to bootstrap your own security,” Arjun remarked. Instead, users can just focus on writing their business logic, “and everything else gets taken over.”

“Compared to spinning up a Cosmos appchain, for example, or Polkadot parachain, spinning up an app rollup is almost free,” he said. 

As a result, Arjun said the evolving L3 landscape is helping to drive down “the cost of experimentation” for Web3 developers. Going forward, he anticipates it reaching a point where launching an app-specific rollup is as cheap and easy as deploying an equivalent smart contract today.