Southland CU API integration (FDX / OpenBanking)

1. SMB accounting auto-sync

Member-owned small businesses in Orange County connect their Southland CU checking account to QuickBooks Online or Xero. Our connector pulls cleared transactions every 30 minutes, normalizes posting date, MCC and counterparty, and writes them into the accounting ledger. The data flows are balances, transactions and pending authorizations, mapped to FDX accounts/{id}/transactions with member consent expiring at 12 months per Section 1033 defaults.

2. Personal-finance aggregation (PFM)

Apps such as budgeting tools and net-worth trackers historically used Plaid screen-scraping for credit unions. We replace that path with a token-based flow modeled on FDX /accounts and /transactions, keeping multi-factor flows on the original Southland CU domain. Refresh tokens carry a rotating consent receipt so members can revoke access from the credit union side without breaking the integration contract.

3. Compliance-grade audit export

Auditors and tax preparers regularly need a full-year transaction export per member. The integration packages all postings, mobile deposit images and Bill Pay history into a signed JSON bundle plus an Excel workbook. Each export carries a SHA-256 manifest and the underlying consent receipt, which together satisfy GLBA recordkeeping for shared-branch and ATM activity through CO-OP.

4. Real-time deposit and transfer webhooks

Property managers and rent platforms need a push notification the moment a Zelle payment lands. We implement a webhook that watches the transaction stream, fires deposit.received and zelle.completed events, and survives the credit union's nightly batch window. Idempotency keys and exponential backoff are included by default.

5. Card-on-file health for fintech wallets

Subscription wallets that hold Southland CU debit cards can listen for block, unblock, lost or stolen events through the Manage Cards module. The integration emits card.status_changed webhooks so the wallet automatically requests a network token update through Visa or Mastercard, preventing failed renewals.

Authorize and exchange tokens

// 1. Member consent + multi-factor on the credit union domain
POST /api/v1/southland-cu/auth/login
Content-Type: application/json

{
  "username": "<member_id>",
  "password": "<password>",
  "device_token": "<biometric_or_device_id>",
  "scope": ["accounts.read", "transactions.read", "deposits.write"]
}

// Response
{
  "access_token": "ey...",
  "refresh_token": "rt_...",
  "expires_in": 1800,
  "consent_id": "cns_8f2b...",
  "fdx_version": "6.1"
}

Pull transactions (FDX-aligned)

GET /api/v1/southland-cu/accounts/{accountId}/transactions
?fromDate=2026-04-01&toDate=2026-04-30&pageKey=...
Authorization: Bearer <access_token>
X-Fapi-Consent-Id: cns_8f2b...

// Response (truncated)
{
  "transactions": [{
    "transactionId": "tx_a14c",
    "postedTimestamp": "2026-04-29T16:11:02Z",
    "amount": -42.18,
    "currency": "USD",
    "description": "TRADER JOE'S #112",
    "category": "GROCERIES",
    "status": "POSTED"
  }],
  "links": { "next": "?pageKey=eyJ..." }
}

Mobile remote deposit capture

POST /api/v1/southland-cu/deposits
Content-Type: multipart/form-data
Authorization: Bearer <access_token>

front_image=@check_front.jpg
back_image=@check_back.jpg
amount=512.40
account_id=acc_91...

// Response
{
  "deposit_id": "dep_55a1",
  "status": "ACCEPTED_PENDING_REVIEW",
  "hold_until": "2026-05-02",
  "micr": {
    "routing": "322281235",
    "account": "*****1234",
    "check_number": "1058"
  }
}

Webhook subscription (events)

POST /api/v1/southland-cu/webhooks
Authorization: Bearer <access_token>

{
  "url": "https://example.com/hooks/scu",
  "events": ["deposit.received", "zelle.completed", "card.status_changed"],
  "secret": "whsec_..."
}

// Delivery example
POST https://example.com/hooks/scu
X-OFL-Signature: t=1714400000,v1=...
{ "event": "zelle.completed", "amount": 250.00, "counterparty": "Jane D." }

US regulatory surface

Southland CU is supervised by the National Credit Union Administration and chartered under California's Department of Financial Protection and Innovation. Any data integration touching member accounts inherits four key obligations: CFPB Section 1033 (consumer-permissioned access, with FDX 6.x recognized as the standard since January 2025), NCUA Part 748 safeguarding rules, the Gramm-Leach-Bliley Act Privacy Rule, and the California Consumer Privacy Act / CPRA. We bake these into the consent receipt, scope strings, and retention windows shipped with every integration.

For background reading, the official NCUA portal documents share insurance and cybersecurity exam guidance that drive how we instrument logging.

What we will and will not do

• Always require a member-authenticated session and a logged consent receipt.
• Replace screen-scraping with token-based, idempotent calls aligned to FDX message names.
• Encrypt artifacts at rest with AES-256 and rotate signing keys every 90 days.
• Honor revocation: a member-side opt-out terminates refresh tokens within 5 minutes.
• Decline requests that would breach the credit union's Member Service Agreement.

Deliverables checklist

• OpenAPI 3.1 specification for every endpoint listed above
• Protocol and auth flow report (token chain, MFA, refresh)
• Runnable source for login, balance and transaction APIs in Python and Node.js
• Mobile deposit reference client with image preprocessing
• Postman collection plus end-to-end integration tests
• Compliance guidance (Section 1033, FDX 6.x, GLBA, CCPA)

Engagement workflow

1. Scope confirmation: data scopes (accounts, transactions, deposits, Zelle, cards).
2. Protocol analysis and FDX mapping (2–5 business days).
3. Build, internal validation, sandbox replay (3–8 business days).
4. Docs, samples, and Postman/CI test cases (1–2 business days).
5. Typical first delivery: 5–15 business days; webhooks and RDC may extend.

About OpenFinance Lab

We are a technical service studio specializing in App interface integration and authorized API integration for global clients. The team's hands-on background covers retail and corporate banking, payment gateways, mobile protocol analysis, and cloud platforms. We are familiar with the FDX 6.x message catalog and the CFPB Section 1033 implementation timeline, and we ship end-to-end financial APIs under explicit security and compliance constraints.

• Financial & banking apps (transactions, statements, transaction integration)
• E-commerce, food delivery, and retail apps (orders, payments, sync)
• Hotel, travel, and mobility apps (booking, itinerary, payment verification)
• Social, OTT media, and dating apps (auth/login, messaging, profiles)
• Source-code delivery from $300 — runnable API source code, full documentation; pay after delivery.
• Pay-per-call API billing — hosted endpoints, no upfront cost, ideal for usage-based pricing.

Contact

Send the target app, the data scopes you need, and any sandbox or member-consent context. We respond within one business day with a scoped quote.

Contact page

What do you need from me to integrate Southland CU?

The target app name (Southland CU, package com.southlandcu.southlandcu), the data scopes you need (balances, transactions, deposits, Zelle, card controls), and any existing member consent or sandbox credentials. Authorized member access is mandatory; we do not bypass authentication.

How long does delivery take for a Southland CU integration?

Typically 5 to 12 business days for a first API drop covering login, balance and transaction endpoints, plus documentation. Mobile remote deposit capture and webhook flows can extend the timeline to 3 weeks.

How do you handle US compliance, NCUA and CFPB Section 1033?

We follow CFPB Section 1033, FDX 6.x message structures, GLBA safeguards and California CCPA requirements. Every call is consent-scoped, logged, and limited to data the member explicitly authorized. We do not screen-scrape against terms of service.

Can I pay per call instead of buying source code?

Yes. Two engagement models are available: source code delivery from $300 with full documentation, or pay-per-call access to our hosted endpoints with no upfront fee, ideal for teams that prefer usage-based pricing during early validation.