Assembler to COBOL Conversion

Companies are rapidly consolidating their technology stacks to reduce costs and maximise IT performance. Our Application Consolidation solution leverages our Automated Refactoring technology to transform relatively obscure languages, such as Assembler, to a common COBOL dialect. This reduces the complexity and footprint of your mainframe source code. Our solution also decreases costs by eliminating licensing fees and reducing risks associated with a shrinking talent pool capable of maintaining Assembler.

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Know the details, reduce the risk: How to begin your mainframe modernisation journey 

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Why modernise?


Scarcity of domain expertise

Developers who understand Assembler are reaching retirement age and no one is being trained to replace them, resulting in a steadily diminishing talent pool. As this shortage grows, the costs and risk of relying on the language will continue to rise.

Limited flexibility

Companies are rapidly moving to modern environments and practises such as DevOps and the Cloud. Assembler and the underlying systems that support it were not designed for modern IT. This results in difficult integrations and limited flexibility.

Exorbitant costs

Mainframes cost as much as 4,500 per cent more to operate than equivalent Cloud counterparts. This figure is compounded by Assembler's rising licensing fees.

Application Consolidation


Many organisations are looking to reduce costs and minimise the risk of a shrinking talent pool by extricating their existing mainframe applications from beneath the weight of relatively obscure languages, such as Assembler. In some cases, the goal is to retain the mainframe and reduce complexity. In other cases, rehosting offers a way to shift applications away from the mainframe infrastructure and into a more modern, cost-effective Cloud environment. In both instances, our Application Consolidation solution is paramount to success.


Our Application Consolidation solution includes the assessment, refactoring, and optimisation of 4GL and procedural codebases to COBOL for maximum maintainability. For example, Assembler, which can be intermingled with COBOL on the mainframe, can be consolidated to COBOL. This eliminates licensing fees and simplifies maintenance of your mainframe application estate. Refactored COBOL code and BMS / MFS maps can be edited and extended using standard development tools, following the same component and naming structure as the original application (even comments are preserved). Developers familiar with the source environment should easily be able to recognise business logic in the refactored COBOL.


Rehosting, sometimes referred to as replatforming, is ideal for companies whose applications are still meeting their business needs, and who therefore wish to retain their core application development skills whilst moving away from non-relational databases and expensive mainframe infrastructure. With rehosting, application source code is migrated onto modern, distributed platforms, either on-premises or in the Cloud, without change. Underlying legacy databases are migrated to relational models, configured to seamlessly interact with your applications via the rehosting platform.

Rehosting solutions are optimised to operate with a core application language such as COBOL. These core languages are retained and rehosted into the target environment of your choice. We leverage our Application Consolidation solution to refactor other application languages within the same estate into the selected, single optimised language. For example, languages such as Assembler, which can be intermingled with COBOL on the mainframe, can be consolidated to COBOL and rehosted, eliminating licensing fees and simplifying maintenance of your application on the rehosting platform.

Automated Refactoring

Our Automated Refactoring software powers the Application Consolidation solution, preserving the benefits of legacy systems whilst empowering organisations to leverage the advantages of a consolidated application stack, whether on or off-mainframe. Many mainframe application transformation solutions create structurally similar programs in the target language but require additional re-engineering efforts to yield desired results.

Our Automated Refactoring software is built for customisation, enabling our team of modernisation experts to fine-tune the tooling rather than the code it produces. This ensures adherence to standards and best practices across the estate. Our Application Consolidation solution was designed with the following requirements in mind:

  • Refactored applications must remain functionally equivalent to their original counterparts

  • Refactored applications must operate independent of third party licensing, libraries, and constraints

  • Refactored applications must be easily maintainable

  • Refactored applications should perform as well as, or better than, the original applications

First, our Automated Refactoring software deconstructs the legacy codebase to isolate source code and classify down to the field level. It then refactors the assets using customised rules based on customer requirements and standards. Remarkably, this turnkey solution retains your valuable business logic without requiring code freezes or additional licensing.

The refactoring process includes flow normalisation, code restructuring, data layer extraction, data remodeling, and packaging for reconstruction. Cloned code is identified and common replacements created – simplifying maintenance and manageability, whilst complex data and control dependency analysis is used to locate and remove dead code. Upon reconstruction, new code structures are generated and deployed into the target environment.

Once the applications are refactored, developers can extend application functionality across the entire estate using the same standard tools and concepts. Precious business logic from the refactored codebase is preserved, making it easy for developers to maintain the refactored code.

Over 35 years of mainframe modernisation experience

More than 500 successful modernisation projects completed

Over 2.5 billion lines of code refactored through automation

Intelligent modernisation, unparalleled experience


Additional insights to help you modernise


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News & Opinions

BLOG // 31-08-2022

COBOL Modernisation Assessment: A Technical Inventory

by Rob Anderson, Vice President of Marketing and Product for Application Modernization

COBOL Modernisation Assessment: A Technical Inventory

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