relay-primary-sources-2026-04-26

Relay primary-source snapshot

Fetched: 2026-04-26 UTC

1) Docs home and documentation index

Source: https://docs.relay.link/ Source: https://docs.relay.link/llms.txt

Selected excerpts from the docs:

The fastest and cheapest way to bridge & transact across chains

App Fees Deposit Addresses Fast Fill Fee Sponsorship Gasless Execution Smart Accounts in Relay Bitcoin Support Solana Support Transaction Indexing Webhooks Websockets

Additional signals from the docs:

• The docs index is unusually revealing because it exposes the real operating surface even where the homepage is visually heavy
• Relay is clearly not documented as a single bridge button; the first-party materials span routing, execution, lifecycle tracking, app monetization, and non-EVM support
• The breadth of feature and API pages suggests a developer control plane layered on top of solver-based cross-chain execution

2) Unified quote API

Source: https://docs.relay.link/references/api/get-quote-v2.md

Selected excerpts from the docs:

This API returns an executable quote for swapping, bridging and calling

Additional signals from the docs:

• The OpenAPI schema includes origin chain, destination chain, currencies, arbitrary destination-chain txs, gas limits, and an authorizationList for EIP-7702 execution
• This makes Relay broader than a simple bridge quote API; the product is designed to coordinate execution workflows across chains
• The public API host and testnet host are documented directly in first-party materials, which strengthens the case that the API surface is core product infrastructure

3) Smart accounts guide

Source: https://docs.relay.link/references/api/api_guides/smart-accounts.md

Selected excerpts from the docs:

Relay uses ERC-4337 and EIP-7702 to enable smart wallet features like gas sponsorship, batching, and cross-chain execution

Batch multiple actions into one atomic call

Delegate tx execution to the user, preserving msg.sender on the destination chain

Sponsor gas or use ERC-20s for fee payments

Additional signals from the docs:

• Relay explicitly positions smart accounts as foundational to its cross-chain infrastructure rather than as an unrelated wallet feature
• The guide is unusually concrete about why ERC-4337 and EIP-7702 matter in a solver model, especially around preserving user identity on destination chains
• This is strong evidence that Relay should be cataloged as execution / smart-account infrastructure, not only as bridge aggregation

4) Bitcoin support guide

Source: https://docs.relay.link/references/api/api_guides/bitcoin.md

Selected excerpts from the docs:

Relay supports deposits to and withdrawals from Bitcoin across any supported chain.

Bitcoin transactions use Partially Signed Bitcoin Transactions (PSBT) for signing.

Unlike EVM chains that track account balances directly, Bitcoin uses a UTXO (Unspent Transaction Output) model.

Additional signals from the docs:

• The docs define Bitcoin-specific chain and currency identifiers and integration behavior, which shows Relay extends beyond generic EVM routing
• PSBT handling and UTXO balance guidance are high-signal implementation details that would be unnecessary if this were just a thin frontend aggregator
• This broadens the project’s category toward cross-chain execution infrastructure with non-EVM support

5) Supported routes and live chain directory

Source: https://docs.relay.link/references/api/api_resources/supported-routes.md Source: https://api.relay.link/chains

Selected excerpts from the docs:

Relay currently supports multiple cross-chain routes across 69+ blockchain networks.

Additional signals from the public materials:

• The supported-routes page is backed by live data from https://api.relay.link/chains
• The live chain response exposes a substantial supported-network inventory, featured tokens, per-chain metadata, bridging flags, and fee parameters
• This is useful primary evidence that Relay operates a real multichain routing and liquidity surface rather than documenting hypothetical support

6) Webhooks and transaction indexing

Source: https://docs.relay.link/references/api/api_guides/webhooks.md Source: https://docs.relay.link/references/api/api_guides/transaction-indexing.md

Selected excerpts from the docs:

Rather than polling the API for status updates, webhooks push transaction lifecycle events directly to your server the moment they happen.

Relay provides two key APIs for transaction indexing

Additional signals from the docs:

• Relay exposes pushed lifecycle events and explicit indexing APIs, including support for same-chain actions and internal-deposit detection
• This indicates Relay also ships operational observability and indexing primitives for integrators
• Those surfaces make the product meaningfully broader than a quote-only API

7) SDK and protocol repos

Source: https://github.com/relayprotocol/relay-kit Source: https://raw.githubusercontent.com/relayprotocol/relay-kit/main/README.md Source: https://raw.githubusercontent.com/relayprotocol/relay-vaults/master/README.md Source: https://raw.githubusercontent.com/relayprotocol/relay-depository/master/README.md

Selected excerpts from the repos:

Relay is the Fastest and Cheapest Way to Bridge and Transact Across Chains.

This SDK facilitates interacting with the Relay protocol.

A cross-chain liquidity protocol that enables fast bridging of assets across multiple blockchain networks. This monorepo includes smart contracts, backend indexer, claimer service, and shared packages.

The Relay Depository is a cross-chain protocol that securely manages user deposits and enables controlled withdrawals through a trusted allocator mechanism.

Additional signals from the repos:

• The public repos show that Relay publishes more than SDK wrappers: first-party code covers contracts, a backend indexer, claim-processing services, and shared packages
• The vaults repo describes an LP and bridge architecture, while the depository repo shows older but still useful protocol explanations and audit references
• Together, these repos make the underlying execution and settlement stack much more legible than the marketing copy alone

Notes

• This pass did not locate a classic standalone whitepaper or litepaper from official Relay sources.
• Relay appears best categorized as cross-chain execution / bridging / smart-account infrastructure.
• The strongest primary materials were the docs portal, documentation index, API reference, Bitcoin and smart-account guides, live chain API, SDK repo, and protocol repos.