Re-introducing Bubs: the first public testnet of Celestia x OP Stack

Re-introducing Bubs: the first public testnet of Celestia x OP Stack

Hello friends! After a brief hiatus, our public OP Stack x Celestia DA testnet is back and better than ever, now running on Celestia's Oolong upgrade. Now named Bubs, this testnet is running on the Goerli testnet and uses Celestia as its native DA layer.

Why Celestia for DA?

Data availability is one of the most crucial yet challenging aspects when dealing with rollups in blockchain technology. In essence, rollups are solutions that execute transactions "off-chain", then post the data and results back to the main blockchain. This approach indeed boosts scalability by reducing network congestion and lowering transaction costs. However, traditional rollups that post data to Ethereum are still bottlenecked by the Ethereum L1's underlying data throughput and high costs.

Enter Celestia, the knight in shining armor for the data availability problem. Celestia provides a modular data availability layer - think of it as a highly reliable, dedicated blockchain, strictly optimized for data throughput. Rather than having to rely on the Ethereum network for all transaction data (which can be congested and expensive), chains like Bubs can instead use Celestia. Celestia provides scalable, efficient DA, and chains using Celestia only have to download data relevant to them.

Furthermore, even if used completely for data availability, Ethereum calldata can only support a few hundred transactions per second. For rollups to grow beyond that, more scalable DA solutions like Celestia are absolutely needed.

About Bubs

Bubs is the first live blockchain to make use of Celestia's newly released modular DA interface for the OP Stack. Bubs is a fully-fledged rollup settling on the Ethereum Goerli Testnet, complete with a faucet, bridge, and block explorer.

Getting Started

Navigate to the Bubs Hub Page, where you'll find chain details, a faucet, and a link to the Bubs block explorer.

Press the "Add Chain to Metamask" button, or add the Chain details manually via your wallet's UI

Network Name: Bubs testnet
Chain ID: 1582
Currency symbol: gETH
Block explorer URL:

You can then request testnet tokens to your wallet by clicking the "request faucet funds on Bubs rollup" button.

Bubs Block Explorer

You can view transaction data via the Bubs block explorer. The block explorer contains information about each block, transaction, address, and token on the network.

The Bubs block explorer also exposes API routes for developers, the documentation of which can be accessed here.

About Caldera

Now, about us at Caldera. We're passionate about enabling teams to launch and operate their customizable rollups. We strive to create a dynamic and versatile ecosystem for decentralized apps and blockchains, and Bubs is a testament to that.

Our alliance with Celestia has added a key ingredient to our tech recipe. Celestia's modular DA solution represents a monumental leap in blockchain technology, and we're excited about the endless possibilities it brings to the table.

We're delighted to offer Celestia DA as a feature of Caldera chains. If you're keen on building with Caldera and interested in launching your own Caldera chain with Celestia DA, we're all ears! Our team stands ready to assist you in transforming your ideas into reality.

As we embark on this exciting journey with Bubs, we look forward to driving the future of blockchain technology together with you, our partners in innovation. If you're ready to join us on this exciting adventure, let's connect and work towards a more scalable, efficient, and accessible blockchain future.