Integration spotlight

OpenLegacy + Pega: safer mainframe-to-Pega coexistence

Pega systems customers can move mainframe workloads incrementally by running legacy and modern applications side by side. With Legacy–Modern Coexistence, OpenLegacy exposes existing host logic as System APIs, enables COBOL and RPG to call modern HTTP services through Reverse APIs, and applies controlled routing so modernization can happen without a big-bang cutover.

OpenLegacy and Pega systems

Move safely, not all at once

Expose existing CICS and connector operations as inbound System APIs so Pega can consume proven host logic while modernization continues in phases.

Let legacy call modern services

Generate Reverse API COBOL and RPG clients so host applications can participate in modern HTTP-based workflows instead of remaining isolated.

Control the coexistence path

Use AtomIQ modernization routing to register, approve, and reverse cross-application dependencies during incremental decoupling.

Safe mainframe to Pega coexistence
Safe mainframe-to-Pega coexistence with OpenLegacy routing, APIs, and incremental modernization.

Capability

Reverse Engineering & Business Specs

Before forwarding work into Pega Blueprint, teams need trusted documentation based on what the legacy estate actually does. OpenLegacy turns discovered operations, code-base exports, and real terminal journeys into living business specifications rather than blank-page documents.

OL Spec, with AtomIQ and TermIQ inputs, helps teams refine process specs with AI chat, plan API boundaries, define shared business models, compare versions, and play UI, service, or 3270 flows in-browser before scaffolding and code generation.

Feature

Plugins & Codegen

Plugins extend OL Spec workspaces with code generators, scaffolding, and integrations that support forward engineering from approved specs. Teams can enable plugins, configure connection values, run setup once, then execute workspace-wide builds or per-operation actions.

After a run, generated artifacts can be viewed, previewed, or downloaded as a ZIP. This gives modernization teams a practical path from reverse-engineered business specs to generated assets that can support Pega Blueprint-driven delivery.

How the coexistence path works

1. Discover and document

Use reverse engineering to identify operations, terminal journeys, business processes, API boundaries, and shared models.

2. Expose and connect

Create inbound System APIs for Pega consumption and Reverse APIs so legacy COBOL and RPG can call modern services.

3. Generate and route incrementally

Run plugins and codegen for scaffolding, then manage cross-application routing with AtomIQ as workloads shift safely toward Pega.

Modernize mainframe workloads with Pega at your pace

Use OpenLegacy coexistence, reverse engineering, and codegen to reduce cutover risk while turning legacy knowledge into Pega-ready modernization assets.

OpenLegacy and Pega systems