Keeping digital banking resilient through a core migration

A regional bank was migrating core systems while serving millions of daily users. Incidents were frequent and costly. Eximus hardened critical services, rehearsed recovery, and improved observability to keep channels stable through the migration.

Client and context

The bank operated multiple digital channels while upgrading its core. Reliability and auditability were mandatory.

• Sector: Banking.
• Size: Regional bank with high daily transaction volume.
• Key systems: core banking services, SQL Server, Azure-based monitoring.

Challenge

Maintain channel uptime and cut incidents during a risky core migration.

• Frequent incidents with unclear ownership.
• Limited observability and slow recovery steps.
• Regulatory scrutiny on availability and evidence.
• No room for downtime during cutover windows.

Our approach

We combined hardening, observability and rehearsed recovery.

• Hardened critical services and adjusted configurations.
• Introduced observability for critical flows with actionable alerts.
• Defined failover runbooks and ran DR tests before milestones.
• Set up on-call processes with SLAs and communication templates.

Results

• Zero unplanned downtime during the migration window.
• 32% fewer incidents quarter over quarter.
• Faster incident response with clear owners and playbooks.
• Audit-ready evidence of DR rehearsals and incident handling.

Tech & services used

• Core banking services, SQL Server, Azure monitoring/alerts.
• Services: GeneXus Support, Backup, DR & Resilience.

Lessons learned

• Observability plus clear ownership reduces noise and speeds recovery.
• DR rehearsals before major milestones prevent surprises during cutover.
• Standardized on-call processes improve communication under stress.

Next step

If you are modernizing core systems and must keep channels stable, we can review your current resilience gaps and plan rehearsals. Contact us to discuss the safest path forward.