a00 - Decentralized Storage Protocol

a00 is a decentralized storage protocol built on U2U, powered by IPFS.

a00 is an ecosystem of tools for anyone to store their files. a00 has its own SDK, its own IPFS nodes, and its own web application. Everything is open-source and transparent.

Ecosystem

Our ecosystem has 3 main components for builders:

Web Platform
a00.js SDK
Smart Contracts and A00 Token

Web Platform

a00 Web platform is the gateway between builders and files. Every developer must create an API key from a00 web platform in order to start building on a00 ecosystem.

After creating an API key, you must deposit some A00 tokens into the Vault contract. The storage fees are paid from the vault contract, without requiring the file owners to interact with the protocol again after they deposit a sufficient amount of A00 tokens.

If you deploy the project by your own, you can use it on the U2U Nebulas testnet, which also has a Faucet for everybody to test it. Faucet leaks A00 tokens every 24 hours.

a00.js SDK

This is a Node.js library that lets developers interact with the protocol programmatically. It wraps necessary HTTP requests as easy-to-use Typescript methods. Usage is as easy as that:

const a00 = new A00("YOUR_API_KEY");

const id = a00.upload("/path/to/file");

const fileContent = a00.get(id);

a00.delete(id);

You can install a00.js by running the command npm install a00.js or pnpm add a00.js

You can read more about it from the a00.js official documentation

Smart Contracts & A00 Token

a00 has 2 main contracts:

Solaris Mainnet:

A00 Token: 0x2B66bF50d553d23C9185021e73CB20A536eAC908
Vault: 0x3C66864bAe5e651096151F5D6fA4509D49B77aC8

Nebulas Testnet:

A00 Token: 0xbaf0b03c3447898040182fB205f19E0c8bB93C73
Faucet: 0x8Cdf68cd62689fa0e2a59b9e29b2f162427DeB57
Vault: 0x80193060e3B241D678c177f2f1aEEe1ad3449747

All contracts are verified using standard JSON outputs. You can directly read the source codes from U2Uscan.

A00 Token

A00 token is the native utility token of a00 ecosystem, responsible of storage fees.

Faucet

Until A00 token is available for anyone to trade, you can use the faucet on the Nebulas testnet to test a00.

Vault

This contract handles token deposits & withdraws. A deposit is necessary for a developer to store their files on a00.

pay() method is responsible for collecting fees from vault wallets, called by contract owner every 3 hours.

The mathematics behind the vault contract is utterly simple, allowing anyone to understand the logic while providing a strong economy model. I cite these words from a00 Whitepaper:

The Vault holds custodied A00 and maintains an internal liability ledger B_i(t) for each user i. Storage consumption is measured off‑chain as bytes b_i over a period, and the owner submits these metered values. Let p denote the price in tokens per MiB. With 18‑decimal base units, one MiB corresponds to 2^20 bytes and 10^18 base units per token.

Deduction rule:

Price per MiB: p
Base units per MiB: u = p * 10^18
Bytes to MiB: m_i = b_i / 2^20
Per‑user deduction: D_i = min(B_i, floor(m_i * u))
Balance update: B_i(t+) = B_i(t) − D_i

In the reference implementation p = 1 (one token per MiB), which matches the on‑chain computation D = floor(b * 10^18 / 2^20). The pay() routine aggregates deductions in O(n) over current holders. Because the function does not transfer tokens out, liabilities decrease while tokens remain custodied, enabling later treasury disbursement or provider settlement via an explicit sweep function (an extension point).

Tech Stack

Web app is built using Next.js 15, React, shadcn, Tailwind, ethers, RainbowKit, and Zustand.

Server is built using Express.js, socket.io, Helia (IPFS), and MongoDB.

a00.js SDK is a Node.js library built with Typescript.

For smart contracts, Solidity and Hardhat are used.

Deployment

Start MongoDB and IPFS instances.

You need to clone the Web and Server repositories. Each repository has its own deployment instructions in the README.md file.

Start the Express server, then the Next.js application. If you want to make changes on smart contracts, you can clone Hardhat environment and the contracts from Smart Contract repository.

U2U Integration

a00 is built on the U2U network, and all smart contracts are deployed on the Nebulas testnet and Solaris mainnet.

Economy

A00 Token has 100,000,000,000 (100 billion) total supply. Every 3 hour, a fee is collected by vault contract from every single wallet that is storing an active file on the protocol.

The fee amount is calculated with the formula: (fileSizeAsBytes) / (1024^2)