Industry Insights

AI-driven Banking Modernization: How to move beyond COBOL without breaking the bank?

Malavika Kumar
Published Dec 08, 2025

Key Takeaways

  • AI now enables banks to modernize COBOL systems by extracting business logic—not rewriting core code.

  • Banking modernization accelerates when mission-critical rules become machine-readable and transparent.

  • AI-driven logic extraction gives banks agility without risking mainframe stability.

  • Once COBOL logic is lifted into an interpretable environment, it becomes accessible to AI, APIs, and human workflows.

  • Banks adopting AI-first modernization gain faster product cycles, better compliance, and lower operational risk.

AI isn't here to rewrite the mainframe, it’s here to understand it. In the new era of banking modernization, AI for banks means being able to extract, interpret, and operationalize decades of COBOL logic without destabilizing mission-critical systems or replacing what already works. COBOL, which is short for Common Business-Oriented Language, is a decades-old programming language that still powers most of the world’s financial systems. Built for reliability, it became the silent engine behind core banking operations.

For years, global banks have invested billions in cloud, data, and AI. However, their most critical platforms continue to whisper in COBOL. It’s a paradox: the future of banking is powered by systems designed for punch cards.

Core ledgers, credit engines, and settlement platforms remain anchored to mainframes built for stability, not speed; for control, not constant change. These systems have delivered reliability for decades, but today they increasingly serve as the quiet barrier between ambition and agility.

Recent moves by leading institutions reveal a new direction. Microsoft and Bankdata, for example, have launched open frameworks designed to extract and understand COBOL logic, not rewrite it. The message is clear: the next competitive advantage in banking modernization lies not in migrating away from COBOL, but in making its logic transparent and usable across AI-driven architectures.

The real problem isn’t COBOL, it’s logic lock-in

Banks have spent decades replatforming, rehosting, and wrapping mainframes with APIs. But the core challenge remains: the business logic is still locked inside procedural COBOL code.

Every credit policy, collateral rule, P&L adjustment, liquidity calculation, and compliance check sits embedded in syntax that no AI model, rule engine, or workflow system can easily interpret.

If the rules can’t be inspected, audited, or adapted quickly, they become a structural bottleneck. This prevents banks from achieving true agility or enabling AI across the enterprise.

This is the gap between “digital transformation” and actual modernization.

AI-driven logic extraction: turning the core inside-out

Unframe’s AI-driven approach to COBOL modernization extracts business logic from legacy systems and rebuilds it in a secure, interpretable JavaScript environment — without rewriting the mainframe or risking production stability.

How it works

Extract. Interpret. Integrate.

  • Extract: Map COBOL functions, data flows, and dependencies with AI-powered code understanding.

  • Interpret: Identify and lift business rules—pricing, limits, validations—into modular, transparent components.

  • Integrate: Deploy the components into a secure JavaScript runtime where they can be consumed by AI models, APIs, and human interfaces.

Once business logic is lifted out of COBOL, it becomes machine-readable—and suddenly accessible to every AI agent, analytics pipeline, and decision system in your stack.

This is banking modernization without the risk, cost, or multi-year timelines of core replacement.

Practical use cases for AI-driven COBOL modernization

Commercial banking

Loan pricing and approval logic extracted from COBOL and deployed in AI-driven rule engines.

Impact:

  • Dynamic rate and collateral adjustments in hours, not quarters
  • Real-time integration with market data for risk-based pricing
  • 65% faster loan origination and improved transparency

Investment banking

Margining, settlement, and P&L attribution rules modularized into API-first services.

Impact:

  • 40% fewer post-trade reconciliation breaks
  • Full lineage and auditability for MiFID II / EMIR
  • Rapid response to regulatory rule changes without editing COBOL

Retail banking

Customer onboarding, scoring, and servicing logic unified under AI-orchestrated workflows.

Impact:

  • Onboarding reduced from 40 minutes to under 10
  • No more duplicate data entry or screen switching
  • Unified cross-product customer view

Risk & compliance

Basel IV, IFRS 9, and liquidity formulas refactored into transparent, testable modules.

Impact:

  • Faster policy updates
  • Automated control validation
  • 30–50% reduction in regulatory audit cycles

Treasury & finance

Legacy balance-sheet, funding-cost, and ALM models rebuilt as event-driven services.

Impact:

  • Intraday liquidity analytics on cloud
  • Scenario simulations in minutes, not overnight
  • Lower compute spend and faster close cycles

Payments & operations

Batch COBOL settlement logic transformed into real-time, message-driven flows.

Impact:

  • Cutoff times eliminated
  • Native integration with ISO 20022 and open banking APIs
  • Up to 50% fewer manual exceptions

Closing thoughts

The future core of your bank won’t be rewritten, it will be understood.

You’re building AI models that must interact with decision logic: pricing, credit, risk, compliance. But if these rules remain locked inside COBOL, your AI can’t learn from them, align with them, or operate alongside them.

Because COBOL isn’t the enemy. Opacity is.

Unframe makes your core systems machine-readable—safe, transparent, and ready for an AI-first future. This is how banking modernization finally breaks free from the constraints of legacy code, without breaking what already works.

Malavika Kumar
Published Dec 08, 2025