Build a custom Acumatica payment “Processing Center” plug-in (C#/.NET) that appears natively under Banking → Processing Centers (CA205000) and supports: Authorize, Capture, Void, Refund Recurring/Subscriptions (via NMI) Tokenization / customer vault usage Hosted payment form option (to minimize PCI scope) Acumatica supports custom payment plug-ins and provides a working sample (“Dummy Credit Card Plug-in”) that we will use as a scaffold. Deliverables Plug-in Assembly (DLL) Implements Acumatica payment interfaces (v2) used by Processing Centers (entry point patterns shown in Acumatica’s sample repo). Supports: Auth, Capture, Void, Refund, Sale (Auth+Capture), and Recurring mapping to NMI operations. Hosted/redirect flow (optional) with response parsing (hosted form response parser pattern referenced by community threads). GitHub+1 Processing Center Provider Shows up as a provider choice on CA205000 once the DLL is deployed and the Custom Payment Plug-In feature is enabled. Provider settings UI (keys, URLs, test mode, logging, timeouts) NMI Integration Direct calls to NMI Payment API for auth, capture, void, refund, and subscription management (create/update/cancel plan or schedule), plus card tokenization (customer vault). Error/decline handling mapped to Acumatica’s result/AVS/CVV fields. Documentation Admin guide (install DLL, enable feature, create Processing Center, map Payment Methods, test credentials). Developer guide (class diagrams, interfaces implemented, config keys, error codes, logging). Support playbook (common errors, how to enable verbose logs, rotating keys). Test Assets Test plan & test data (cards/tokens) for NMI sandbox. Postman/HTTP files (if needed for hosted-form callback simulation). QA checklist tied to acceptance criteria (below). Functional Requirements (Mapping) User Action in Acumatica NMI Call Result in Acumatica Authorize on SO/AR Payment type=auth Transaction ID stored; payment status = Authorized Capture authorized payment type=capture (amount ≤ auth) Payment marked Captured/Settled; doc updated Void pre-settlement type=void Payment released/voided; doc updated Refund (full/partial) type=refund Refund lines created; links to original txn Sale (one-step) type=sale Immediate settle; payment recorded Recurring/Subscription NMI subscription APIs Schedule created; status reflected in Acumatica (store plan/ID) Reference for Processing Center/Payment setup and samples: Acumatica sample plug-in repo and Processing Center setup guides. GitHub+1