The API orchestration layer within a payment architecture is the software tier that abstracts multiple backend services (gateways, acquirers, token vaults, fraud engines) and exposes unified APIs to developers. In Hellgate.io’s composable ecosystem, the Commerce and Hub modules form part of this layer—enabling developers to integrate once and get access to multiple payment flows, acquirers, tokens, wallets, and decision engines. This approach drives scalability, modularity and faster time-to-market.