The Modern Treasury API is organized around REST. Our API has predictable resource-oriented URLs, accepts JSON request bodies, returns JSON-encoded responses, and uses standard HTTP response codes, authentication, and verbs. You can use the Modern Treasury API in a sandbox environment without affecting your live data or interacting with real banking networks. The API key you use to authenticate determines whether a request runs in live mode or in the sandbox.
By default, sandbox environments are configured for payment service provider (PSP) use. If you're a first-time user getting started with Modern Treasury through the PSP, refer to the Payments Quickstart. If you're looking to integrate Modern Treasury directly with your own bank account, refer instead to the Bring Your Own Bank Quickstart. If you plan to use the Modern Treasury Ledger to power your platform, check out the Ledgers Quickstart.