The Web3 data economy is booming. Users and builders need better privacy for their data, which Oasis delivers. But they also need better tools for analyzing, managing, and using their data. 

This is why Oasis built Nexus. 

In this article, core features and use cases for Oasis Nexus are explored in addition to behind-the-scenes development insights and what is coming next for Oasis ecosystem tools like Nexus. 

‍What is Oasis Nexus? 

Launched in July 2023, Oasis Nexus (f.k.a., Oasis Indexer or simply the Explorer backend) is the premiere data-fetching backend for the Oasis Network ecosystem. Nexus was incubated internally for several months before its public launch. With Nexus, the Oasis core team aims to serve as the backend for explorers and wallets, most notably Oasis Explorer and Oasis Wallet.

Oasis Nexus is not just an indexer, but it serves as a critical conduit for accessing onchain data on the Oasis Network. Nexus continuously fetches blockchain data from one or more Oasis nodes and other related sources (explained more below). This onchain data is parsed and stored into a heavily indexed SQL database. Nexus provides a JSON-based web API to access the data. 

You can access a Nexus instance maintained by the Oasis Protocol Foundation on nexus.oasis.io. Or, in a true decentralized peer-to-peer spirit, you can head over to the official GitHub repository, explore, build and run Oasis Nexus by yourself!

Finally, watch a tutorial on how to use Oasis Nexus on YouTube.

‍Key Nexus Features

This section unpacks some key features and design characteristics of Nexus.

For starters, the API adheres to OpenAPI Specification (OAS) 3.0 for compatibility with a wide array of systems. The API also offers foundational routes, including latest block numbers and times, which are crucial for making life easy for Web3 builders and the dApps and other onchain applications they create.

Data surfaced by Oasis Nexus is sourced dynamically from multiple entities. One primary source is the Oasis node connected to the consensus and ParaTime layers. Ancillary sources include:

• The metadata registry, which is essential to Nexus since it functions as a repository for validator metadata.
• Sourcify, which provides verifiable source code for EVM smart contracts, and also allows Nexus to present fully interpretable (i.e. parsed) EVM transactions and events, as opposed to binary blobs.
• IPFS, through which Nexus gathers additional details about individual NFT instances.

Beyond data queries and visualizations, the indexer feature of Oasis Nexus can be a powerful analytical tool for accounting and tax records. The Nexus indexer is tailored to provide account-centric event and transaction histories that are essential for accurate and detailed financial audits, tax accounting and other financial tasks. 

‍Behind-the-Scenes Nexus Development

For core contributors at Oasis Engineering, development of products like Nexus is exciting. Nexus isn't an isolated tool inside the Oasis ecosystem, but it’s actively integrated and improved along with other primarily frontend projects. These other projects include Oasis Explorer and Oasis Wallet, which are all constantly developed for improved feature richness, robust privacy, and real utility.

Development is also rapid and continuous. Here are just a few of the key Nexus upgrades deployed in 2023. 

• Support added for indexing both Ethereum-native unencrypted transactions as well as Oasis-specific encrypted transactions.
• Support added for indexing ERC-721 NFTs and tracking changes in wallet asset balance.
• Added both Oasis native and Ethereum address-related search functionality to its API. 
• Added account-related queries that are compatible with the existing Web3 wallet tooling.
• Added support for querying archive nodes regardless of their API version, thus making it possible to (re)index data going far back in time.

Read more in-depth updates about Nexus development from monthly Oasis engineering reports. 

‍What’s Next for Nexus? 

Oasis Nexus is not a static product! Immediate development priorities for Nexus include expanding support for the Oasis consensus layer, making overall network support more robust, and developing fluid interoperability with Oasis parallel runtimes. 

As with other projects, Oasis engineering is constantly testing and shipping new updates to future-proof this core ecosystem tool. Architectural augmentations, performance improvements and new feature support are coming. Stay up to date with monthly updates on Nexus and other Oasis tools right here on the Oasis blog. Or chat with Oasis engineers, users, and other community contributors in the official Oasis Discord server.