This document serves primarily as a guide to Apex's key infrastructure and technical overview.


At a high-level the Apex Wallet breaks down into the following components:

  • Apex Extension
    • UI and Infrastructure.
  • Content Injection and DApp Integration
  • The RPC Engine
  • On Device Storage
  • Apex Backend Services
    • Messaging
    • RPC Requests for NFT, Tokens, and History

The Apex Extension

Apex allows users to manage account keys, transact Ethereum-based tokens, broadcast EVM transactions, message EVM addresses, and securely connect to decentralized applications through a compatible web browser. Apex is non-custodial, which means Apex does not hold your assets on your behalf. You own them directly, thanks to the power of cryptography and the Ethereum blockchain.


When no accounts are associated, Apex opens an onboarding window prompting a user to create or import an account. Under the hood, Apex uses the polyfill open source library to manage windows, tabs, and popups for browsers.

On-Device Storage

Once an account is created/imported, private account information is stored via password encryption directly on the device with IndexDB. Any account configuration and private data are only accessible to the extension. The Apex backend servers do not track account information besides the account's public address for messaging.

For more information on how any onboarded accounts are created and stored, please see Key Generation. Apex uses crypto-js and Ethers.js for encryption and account generation.


In App

Apex's UI is built to be a fun, simple, and secure way to control your crypto assets and interact with the world of web3. Apex UI is built using React, Node, & Typescript. The underlying infrastructure leverages Alchemy as an RPC provider, although users can configure a custom RPC provider in-app.

Communication with Apex's servers is secured via wallet signatures authorized with user password prompts in the Apex extension. It is impossible to impersonate accounts without the private key of the EVM account.


Apex's messaging data and API is completely off-chain and maintained via Stream-Chat API. The current implementation prioritizes:

  • Indexing, Speed, & Reliability
    • Performance that doesn't rely on proximity to a regional data center.
  • Security and Data Protection with In-Transit Encryption.
    • All data is encrypted both in transit and at rest via TLS/SSL
  • Data Compliance
    • Including Moderation and Reporting

The messaging infrastructure allows users to securely send dynamic content types, share online statuses, and support group and p2p threads.


NFTs, Tokens, and History

Apex is excited to partner with Alchemy to provide top-notch experiences via the Alchemy API: https://docs.alchemy.com/reference/api-overview. Some of the features include:

  • Automatic and Customizable token watch lists
  • Full transaction history
  • Send/receive messages and assets to ENS usernames instead of long addresses
  • Multiple wallet support and a way to quickly switch between them
  • Robust NFT support, including ERC-721s and ERC-1155s
  • Native L2 support with Optimism, Arbritrum, & Polygon

Apex maintains its connection with the Alchemy RPC Provider. However, users can opt to use a custom RPC provider for transaction and balance operations.


Content Injection and DApp Integration

Decentralized applications connect, authenticate, and integrate EVM functionality with a user's address via Apex's background and content-injected JavaScript code. The injected libraries allow websites to send actions, request signatures, or request transactions to the user through Apex as an intermediary.

Communication with DApps

The Ethereum JavaScript provider handles communication in Apex between DApps. This provider synchronizes its state and marshals JSON-RPC messages via a duplex stream. The Apex Inpage Provider supports legacy provider interfaces in addition to EIP-1193 and instantiates the object injected by Apex into web pages as window.ethereum.

The Apex extension and provider communicate via a background.js service worker adhering to google chrome's manifest v3 spec.

The RPC Engine

Apex leverages the open-source library JSON RPC Engine to handle authorized requests from decentralized applications. DApp connection status and unacted requests are stored in IndexDB only on the active device.


The following outlines potential interactions between DApps and Apex.

DApps can ask Apex to

Ask for address via eth_requestAccounts(connect)Requires user action
Send transaction via eth_sendTransactionRequires user action. Depending on the contents of the transactions we will need to show different things, e.g. if approve method for erc20 contract then show approval modal
eth_decrypt eth_getEncryptionPublicKeyRequires user action
RPC read calls (eth_call, eth_getBalance, etc)Used Alchemy RPC or the custom API specified by the user.
Switch network via wallet_switchEthereumChainSwitches the active network for the wallet. Requires user action

Apex emits to DApps

Account changed via accountsChanged eventApex provider library listens for metamask_accountsChanged notification with { address }
Chain changed via chainChanged eventNotify via metamask_chainChanged notification with { chainId }
Wallet connected via connect- Handled by Apex provider library and queryable by DApps by eth_requestAccounts.
Wallet disconnected via disconnectEmitted by the background.js service worker.



The Apex team is always looking to improve the product and technical approaches; if you have thoughts, comments or questions, reach out to us on the discussion page or email [email protected]!