Blockchains have come a long way in solving scalability challenges. Rollups made blockchain faster and cheaper, decentralized applications (dApps) more usable, and RPC nodes made dApp development more accessible.
But with Web3 adoption growing fast, can rollups handle millions of users without slowing down? The answer might lie in giving every application its own dedicated space – an AppChain.
Will every app eventually become a blockchain or a rollup of its own? Let’s debate.
The evolution of dApp development
AppChains introduced a new idea of how decentralized applications may be built and scaled. Blockchain developers now have to think in terms of: “Should my app get its own custom blockchain?”
Let’s look into the bigger picture and restore the logic of where this idea and necessity comes from.
1. Early crypto networks: Limited programmability
Early blockchains were not programmable. They were purpose-built for a single application, like Bitcoin for decentralized currency and payments.
Developers who wanted to create new functionality or tailor blockchains for other purposes had to either:
- fork Bitcoin and modify it;
- build their own chain from the ground up including consensus mechanism, tokenomics, and validator network.
This included building and running full nodes, which added costs for hardware and electricity.
In other words, the process was slow, expensive, and required deep expertise.
2. Programmable blockchains: Multi-dApp platforms
First programmable networks like EOS, TRON, and, finally, Ethereum removed the need to build a new blockchain for every new idea. Instead, they offer general-purpose systems that could host multiple applications on the same platform.
Developers can now:
- Deploy decentralized applications (dApps) on Ethereum as smart contracts;
- Leverage Ethereum’s validator network, global distribution, and established infrastructure.
Development became more accessible which led to the explosion of DeFi, NFTs, DAOs, etc.
This era also revealed the critical scalability limitation: networks slow down with high demand and gas fees increasing.
3. L2s and Rollups
Layer-2 solutions, primarily rollups, allowed Layer-1 networks to scale without overhauling their core infrastructure.
Ethereum reduced congestion on its mainnet by outsourcing the processing of a significant portion of transaction volume to rollups. This reduced the gas cost and improved performance for users and applications.
DApp developers can now choose between building on L1 or deploying on L2 and rollups like Polygon, Arbitrum, and Optimism.
However, even with rollups, one application experiencing a surge in traffic may affect the entire network and degrade the performance of all other applications.
4. AppChains
Now imagine a whole rollup is dedicated to serving only one blockchain application:
- It processes its own transactions independently;
- Relies on L1 as a security layer;
- Uses all available resources;
- Can be customized for a specific use case.
This is what the AppChain thesis advocates for: a dApp is now its own blockchain.
5. Rollup-as-a-Service
At this point, it seems we’re back to the starting point: building a whole new blockchain for just one app sounds too complex, expensive, and time-consuming.
In this context, Rollups as a Service (RaaS) becomes the key tool that makes the AppChain thesis practical.
These services offer all the necessary tools and infrastructure, from node networks to AppChain explorers, to reduce the time and cost of AppChain development. So launching an AppChain is not that different than deploying a contract.
What is a rollup in crypto?
Rollups are high-throughput execution layers built on top of the public blockchain.
Instead of doing all the work on the Layer-1 (L1) network which can be slow and expensive, rollups handle most transaction execution and only send summaries of the results back to L1.
How rollups work
Rollups execute transactions on a separate layer, avoiding congestion and costs of the main blockchain:
- Transactions are collected into batches;
- When a batch is processed, the rollup generates summaries or proofs of these transactions (validity proofs for ZK-rollups and fraud proofs for Optimistic Rollups);
- These summaries are submitted to the Layer-1 blockchain;
- All transaction data (or proofs) is ultimately verified and stored on L1.
Source: Arbitrum
Rollups inherit cryptographic security, decentralized validator networks, and data availability guarantees of L1. This is how they’re secured by the underlying blockchain.
For developers and users, building and interacting on Ethereum rollups feels the same as doing so on the ETH mainnet, but with significantly lower costs.
Some examples of rollups are:
- ZK-rollups: Linea, Scroll, ZKsync Era, Starknet, Polygon zkEVM
- Optimistic rollups: Arbitrum, Optimism, Base, Blast, Taiko
In general, rollups are a big step towards scaling blockchains. They are also the primary way that AppChains get added to Ethereum.
What is an AppChain?
In simple terms, an AppChain is a blockchain for one application. It is designed to support a single dApp or a group of applications with similar use cases and are specifically optimized to meet their technical requirements.
Unlike dApps that run on general-purpose platforms like Ethereum or its L2s, AppChains function independently and are not affected by the performance of an underlying blockchain.
At the same time, they integrate and interact with a larger ecosystem (e.g. Ethereum, Cosmos, Polkadot).
App-specific blockchains vs app-specific rollups
Technologies or frameworks like:
- Polygon CDK,
- OP Stack,
- ZK Stack,
- Arbitrum Orbit,
help build Ethereum-compatible rollups – Layer-2 or Layer-3 AppChains – at the speed and cost that makes it viable to launch an infinite number of application-specific chains. These are also called App-Rollups.
Another group of AppChains are:
- Cosmos zones
- Polkadot parachains
- Avalanche subnets
These are independent Layer-1 blockchains (with their own consensus, validators, governance, and state) that are still interoperable with others in their ecosystem.
The main difference is that Cosmos AppChains require more effort to manage validators and security, while App-Rollups rely on Ethereum’s battle-tested consensus, making them easier to deploy.
Below is a list of some examples of AppChains and what technology they build on:
| AppChain | Use Case | Technology Stack | Sector |
|---|---|---|---|
| Unichain (Uniswap) | DeFi-optimized | OP Stack | DeFi |
| Namechain (ENS) | Decentralized domain name service | OP Stack | Infrastructure |
| ImmutableX | Host scalable gaming apps | StarkEX | Gaming |
| Xai | Host blockchain-based games | Arbitrum Orbit | Gaming |
| Hyperliquid | High-performance derivatives exchange | Cosmos SDK | DeFi |
| Ozean (Clearpool) | Tokenized RWA (Real-World Assets) yield generation | OP Stack | RWA |
| dYdX | Decentralized derivatives exchange | Cosmos SDK | DeFi |
L1 blockchains vs Rollups vs AppChains
Both Layer-1 networks and Rollups are general-purpose blockchains, where anyone can deploy new dApps.
This comes with limitations:
- All dApps share the same execution layer and compete for block space;
- Highly popular dApps or events like airdrops and NTF drops may overload the network, cause delays, - and increase costs for other applications;
- Scaling is hindered by the underlying blockchain capacity;
- Developers are tied to the blockchain's programming languages, frameworks, and tools;
- All dApps are equally affected by the decisions of the entire network.
Ethereum Usage by Application Categories / Source: CoinShares
These constraints have made certain use cases such as gaming and complex DeFi services unviable on L1. Rollups partially solve these issues but dApps continue to rely on shared resources.
AppChain benefits for developers
AppChains come to a rescue when an application needs to make more optimal choices for their use case:
- Performance optimization: Developers can fine-tune network parameters to match the performance their applications need;
- Dedicated resources: AppChains operate independently, avoiding competition for block space with other applications.This provides more scaling opportunities.
- Optionality: AppChains offer unmatched modularity. dApp developers can choose settlement, execution, consensus, and data availability (DA) layers and other components from various stacks to compose the chain that works exactly as they need.
- Customizability: If a specific ‘module’ doesn't perform as expected, it can be replaced or modified without rebuilding the entire system.
- Cost efficiency: With specialized chains, projects can reduce fees associated with their specific layer requirements, rather than competing for space on L1 and L2 with all users.
- Low barrier to entry: Rollup-as-a-Service significantly simplifies the AppChain deployment process and costs. Projects and businesses can easily launch a rollup using pre-built, off-the-shelf components.
All in all, an AppChain is a foundation for a more responsive and efficient application with improved usability for end users.
| L1 | Rollups | AppChains | |
|---|---|---|---|
| Infrastructure | Shared by all applications | Shared, but faster and cheaper | Dedicated to a single dApp |
| Performance | Slows under high demand | Handles congestion better than L1s | Fully optimized for specific use case |
| Cost | High gas fees in peak times | Significantly lower fees than L1 | Customizable fee structure |
| Security | Directly secured by native consensus | Secured by the underlying L1 | Customizable |
| Use cases | General-purpose applications | Performant general-purpose applications | Gaming, DeFi, DePIN, RWA Tokenization, enterprise applications |
Comparing L1s, Rollups, and AppChains: Where to Build Your dApp
Conclusion: Why build an AppChain?
Answering the question from the introduction – will every app eventually become a rollup of its own? Most probably no.
General-purpose blockchains remain ideal for dApps that benefit from shared resources and network effects. AppChains is simply a choice developers can now make when their application outgrows the constraints of a general-purpose chain.
The choice ultimately depends on many factors. Here are some to consider:
Does your dApp involve resource-intensive operations, like advanced calculations, frequent state updates, or managing complex on-chain logic?
Do you expect your application to grow significantly in terms of user base or transaction volume?
Does your use case have unique demands existing solutions cannot provide?
Building a custom blockchain is typically beneficial for sectors like Web3 gaming, DeFi, DePIN, and RWA tokenization as their innovative demands do not always fit into existing solutions.
Design the blockchain around your dApp, not the other way around, with GetBlock’s AppChain service. Customize everything, easily grow, scale, and meet your business objectives, backed by GetBlock’s trusted infrastructure.
