Riverstone Credit Union Core Teller

The challenge

Before

Riverstone Credit Union serves 28,000 members across nine branches in Iowa and Nebraska. Their front-line teller experience still ran on a 1990s AS/400 core through a green-screen terminal emulator, and onboarding new tellers took six weeks because the keystroke patterns were undocumented institutional folklore. Member-facing wait times averaged eleven minutes for a simple deposit, and back-office exception handling required printing screens, marking them up, and walking them to a supervisor.

• Green-screen teller terminals requiring memorized function-key sequences
• New teller onboarding taking six weeks before they could work unsupervised
• Eleven-minute average wait time at branch counters for simple deposits
• Exception handling done by printing screens and walking them to supervisors
• No member-facing photo, signature card, or ID image in the teller view
• Cross-branch coverage blocked because each branch trained on its own quirks
• Compliance flags surfaced only at end-of-day batch — never at the counter
• Audit log scattered across AS/400 spool files no analyst could query

The solution

What we built

We built a modern teller and back-office web application that sits on top of the existing AS/400 core through a thin middleware translation layer — so the cooperative did not have to rip out their general ledger. Every teller action is composed in the new UI, validated against business rules in real time, and submitted to the core as a single posted transaction. The teller now sees the member photo, signature card, last-five-transactions, and any compliance flags in one screen before they even greet the member. Supervisor overrides are routed in-app instead of by paper. Cross-branch coverage works because the workflow is identical at every counter. Reporting and audit run off a separate read replica of the middleware database, giving the compliance team direct query access without ever touching the core. We staged the rollout one branch at a time over fourteen weeks, with a rollback path to green-screen still active at each branch for the first seven days.

How the system flows

1. Member Lookup→Compliance Check→Identity Verification→Service Selection
2. Deposit→Validation→Compliance Hold (if flagged)→Core Posting→Receipt
3. Withdrawal→Funds Availability→Photo ID Capture→Supervisor Override (if needed)
4. Cash Order→Vault Reconciliation→Branch Cash Position Report
5. Member Profile Update→Document Upload→Compliance Re-screen
6. Loan Payment→Allocation Engine→Late Fee Logic→Core Posting
7. Exception Routing→Supervisor Queue→In-App Approval→Audit Log Entry

• End-of-day balancing assistant comparing teller drawer to system position
• Cross-branch service identical workflow regardless of home branch
• Audit log streamed to read replica for compliance team self-service