← Capabilities

Legacy–Modern Coexistence

Modernize incrementally—expose System APIs outbound and Reverse APIs inbound—without a big-bang cutover, using OL Integration, OL CoreIQ, OL Code, and OL AtomIQ.

Challenges

  • Big-bang cutovers force a rewrite before modern channels can use host logic, while COBOL and RPG still cannot call modern HTTP services.
  • Screen-bound programs are not service-shaped, so coexistence APIs cannot invoke the same rules without the green screen.
  • Cross-app traffic during decoupling is implicit and irreversible, with no gated routing.

Benefits

  • Expose existing CICS and connector operations as inbound System APIs and multi-technology endpoints without a cutover.
  • Generate Reverse API COBOL/RPG clients and convert screen programs to RPC so host apps can call and be called as services.
  • Apply AtomIQ modernization routing so cross-app dependencies are registered, approved, and reversible.

Run legacy and modern side by side: System APIs for inbound access to host logic and data, Reverse APIs so COBOL/RPG call modern HTTP services, screen-to-RPC for service-shaped programs, and AtomIQ gateway routing for incremental decoupling.

Products

  • OL Integration — legacy connectors and screens flow methods for modern consumption
  • OL CoreIQ — System API bulk creation from CICS and related assets
  • OL Code — Reverse API clients, screen-to-RPC, and Hub asset testing
  • OL AtomIQ — code-first screen flows to Hub and modernization routing/gateway lifecycle

What it covers

  • Inbound System APIs over existing host programs and transactions
  • Outbound Reverse APIs from COBOL/RPG to modern HTTP
  • Screen-to-RPC conversion for coexistence-friendly services
  • Controlled cross-app routing during incremental decoupling

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