Infrastructure for programmable payments

BRRR is a developer infrastructure for programmable payments. It provides APIs and SDKs for building on/off-ramps, and orchestration products. Through BRRR, developers can enable end-to-end payment products across 20+ blockchain networks.

Developers integrate via the Integration API or SDK. End-users or AI agents connect wallets, select tokens, and BRRR handles conversion, compliance, and settlement. Off-ramp to USD, EUR, CHF, or GBP; On-ramp to 30,000+ tokens on 20+ blockchain networks. Orchestration routes assets across chains automatically.

Fintechs that want to add crypto payment capabilities without building blockchain infrastructure. Web3 projects that need compliant fiat rails so their users can actually spend on-chain value. AI platforms that need autonomous agents to make real purchases with real money. And BaaS providers that want to embed programmable payment infrastructure into their own platforms. Each audience has a dedicated integration path and documentation tailored to its specific requirements.

We accept clients from all countries, except US persons, Russian citizens and residents of: Afghanistan, Angola, Bangladesh, Belarus, Burkina Faso, Burundi, Central African Republic, Cuba, Democratic Republic of the Congo, Guinea, Guinea-Bissau, Haiti, Indonesia, Iran, Iraq, Latvia, Lebanon, Libya, Mainland China (Hong Kong and Taiwan accepted), Mali, Myanmar, Nicaragua, Niger, North Korea, Russia, Somalia, Sudan, South Sudan, Syria, Trinidad and Tobago, Venezuela, Yemen, Zimbabwe.

BRRR supports 20+ networks with continuous expansion. EVM networks like Ethereum, Arbitrum, Base, Hyperliquid and others. And other networks like Solana, Starknet, and Tron.

BRRR supports USD, EUR, CHF, and GBP in fiat currencies. All major stablecoins including USDC, USDT, USDE, USDS, and RLUSD; and 30,000+ other tokens across 20+ blockchain networks.

Any holder of the BRRR token can become a Validator by staking tokens into a Security Deposit smart contract — the process is fully permissionless with no approval required. Once staked, validators participate in system operations and earn rewards through a dynamic emission schedule tied to transaction volume and individual contribution. Staking is available across all BRRR-enabled networks, with the protocol maintaining a unified ledger on the Accounting Chain. To exit, validators submit an unstaking request and wait a mandatory 7-day unbonding period while pending obligations are verified before funds are released.

Orchestration is BRRR's cross-chain routing layer. It allows users to Relay any token on any supported network — even if it lives on a different chain than your app is connected to. The API and SDK resolve the optimal path automatically: selecting bridges, computing swap routes, estimating gas, and packaging everything into a single call. No manual bridging, no chain switching, no intermediate tokens. Users see one transaction; BRRR handles the rest.

A three-endpoint HTTP API that gives autonomous agents full control over a Holyheld card.GET /balance reads the current EUR balance.GET /card-data retrieves the card number, expiry, CVV, and billing address for checkout.POST /topup-request converts crypto to EUR and loads it onto the card. No human approval is needed at runtime — agents authenticate with bearer tokens that carry cumulative spending limits set by the account holder.

No. BRRR abstracts blockchain complexity behind standard developer patterns — REST APIs, JSON responses, and an npm package. The SDK manages token approvals, EIP-2612 permit signatures, cross-chain routing, and gas estimation without any direct smart contract interaction from your side. If you've built a typical API integration before, you already have the skills to build on BRRR.

The SDK @holyheld/sdk and REST API are designed for rapid integration. Live demo apps are available for reference. The test environment is accessible immediately with the shared test key. A quickstart guide walks through the full flow from the first API call to completed flow.

Yes. On the SDK side, the $SDKTEST customer executes real on-chain transactions without triggering any fiat settlement, so you can validate the complete flow safely. Use low-fee networks like Arbitrum, Polygon, or Avalanche to keep gas costs under a few cents per test.

Yes. The Payments for AI Agents API is built for fully autonomous, 24/7 operation. Agents can check balances, top up their card, and retrieve card details to complete purchases — all without a human in the loop. Each agent operates with its own bearer token and a cumulative EUR spending limit set by the account holder, so there is always a human-controlled ceiling on what any agent can spend. A ready-made MCP server is available for Claude Desktop, and any framework that makes HTTP calls can integrate directly.