Banking Core System (Community Bank)

Part of the worlds-biggest-software-project initiative.

An AI-native, open-source core banking platform for credit unions and community banks underserved by the legacy Big Three.

The Banking Core System is a candidate project to build a modern, API-first core banking platform purpose-built for US community banks and credit unions in the USD 500 million to USD 10 billion asset range. It targets institutions struggling with legacy green-screen cores, per-module fee structures, and multi-year implementation cycles, while embedding AI capabilities directly into the transaction data layer rather than bolting them on as third-party add-ons.

Why a New Community Bank Core?

The Big Three (Jack Henry, Fiserv, FIS) collectively serve over 70% of US banks, yet user feedback consistently cites outdated UIs, "nickel-and-dime" per-module pricing, and 12–18 month onboarding timelines.
Cloud-native challengers (Mambu, Thought Machine, Finxact) are designed greenfield-first or for Tier 1/2 banks, leaving institutions under USD 500 million in assets without affordable, low-engineering-overhead options.
Apache Fineract is the only production-grade open-source core, but lacks US regulatory modules (BSA/AML, FFIEC, NACHA ACH) without significant customisation.
All commercial vendors rely on third-party integrations for AML and fraud monitoring, creating data latency gaps that an AI-native core operating on the same event stream can eliminate.
Approximately 170 credit union mergers are projected in 2025, the highest rate since 2016, driving demand for scalable platforms that absorb acquired institutions quickly.

Key Features

Core Banking Operations

Deposit account lifecycle for DDA, savings, money market, and CDs
Loan origination and servicing for consumer instalment and lines of credit
General ledger with double-entry accounting and period-close
Customer information management (CIF) with KYC data model
Teller and branch operations UI

Payments & Messaging

ACH origination and receipt aligned with NACHA
Wire transfer processing for Fedwire and SWIFT
ISO 20022 native message support for payment rails
Real-time event streaming for downstream consumers

Compliance & Risk

BSA/AML transaction monitoring with AI-driven alert scoring
FFIEC-aligned audit trail and access control logging
Automated regulatory change monitoring across FFIEC, FinCEN, and CFPB updates
AI-driven fraud detection on ACH and debit card transactions

Open APIs & Integration

REST API with OpenAPI 3.x specifications
FDX-aligned data schema for consumer-permissioned data sharing
Digital banking API layer targeting FDX v6.x
MCP server for AI agent integration on front-office banking actions

AI-Native Advantage

Where incumbents bolt AI onto static rule-based engines via third-party integrations, this project embeds AI directly into the core's event stream. That enables explainable BSA/AML alerts that reduce false-positive burden without compromising detection, predictive overdraft and credit limit recommendations driven by real-time cash flow analysis, NLP-based monitoring of FFIEC, CFPB, and state regulatory updates with impact mapping to core configuration, and a conversational banking assistant for member self-service. Fraud detection runs on the same transaction graph as the ledger, eliminating the reconciliation delays inherent in batch-analytics architectures.

Tech Stack & Deployment

The platform is designed cloud-native and API-first, with REST APIs documented via OpenAPI 3.x and an event-driven architecture suitable for streaming integrations. Data and messaging schemas align with FDX (open banking), NACHA (ACH), Fedwire/SWIFT (wires), and ISO 20022. Deployment targets include SaaS, customer-managed cloud, and integration with the broader fintech ecosystem through a developer portal and sandbox. An MCP server is included for AI agent orchestration with token-based auth, RBAC, PII masking, and audit logging.

Market Context

The US core banking software market is projected to grow from USD 6.09 billion in 2025 to USD 16.81 billion by 2032 at a 15.6% CAGR (Fortune Business Insights, 2025). Core banking contracts for community institutions typically range from USD 500,000 to several million per year, structured per-account, per-transaction, or flat-fee. Primary buyers are CEOs, COOs, CIOs, and IT directors at community banks and credit unions managing core replacements, alongside boards overseeing digital transformation.

Project Status

This project is in the research and specification phase.
Contributions, feedback, and domain expertise are welcome.

Contributing

We welcome contributions from developers, domain experts, and potential users. See CONTRIBUTING.md for guidelines.

Important: All contributions must be your own original work or clearly attributed open-source material with a compatible licence. Copyright infringement and licence violations will not be tolerated and will result in immediate removal of the offending contribution. If you are unsure whether a piece of code, text, or other material is safe to contribute, open an issue and ask before submitting.

Licence

Licence to be determined. See discussion for context.