Connecting mainframe applications to modern systems through APIs can open established data, transactions, and business logic to new applications and services. But API enablement is only one part of creating a modernization model that can hold up as more teams, services, and environments become involved.
Organizations also need consistent development and deployment practices, lifecycle governance, reusable integration patterns, security controls, and clear points of human oversight.
This direction is already taking shape across enterprise mainframe environments. ISG’s 2026 U.S. mainframe research found that organizations are standardizing DevOps pipelines and API-enabled architectures while adopting governance-first frameworks with human-in-the-loop checkpoints. The research points toward structured, phased programs designed to improve delivery while maintaining operational continuity.
Why Is API Enablement Alone Not Enough?
APIs provide a standardized way for modern applications to access established mainframe capabilities. Instead of creating a new point-to-point connection for every application, teams can expose approved transactions or business functions through reusable interfaces.
The challenge comes as the API environment expands.
Each service still needs an owner. Access has to be controlled. Changes need to be tested. Versions have to be managed. Dependencies need to be understood. Teams also need visibility into which services already exist before building another integration around the same underlying function.
The governance gap becomes more significant as APIs multiply. Radware’s 2025 Application Security report found that only 6.1% of respondents had fully documented all of their APIs. Incomplete visibility can make it harder to manage ownership, access, security, dependencies, and lifecycle decisions consistently.
For mainframe environments, API delivery needs to include the controls that determine how those services are created, secured, reused, changed, and retired over time.
Standardized DevOps Creates a Repeatable Delivery Process
Modern API architectures also change how mainframe development fits into the broader software delivery lifecycle.
A service may connect a mainframe transaction to a cloud application, mobile experience, partner system, or automated workflow. Maintaining separate development practices for each environment can make testing, deployment, versioning, and troubleshooting more difficult.
Standardized DevOps practices create a more consistent path from development through production. CI/CD pipelines can incorporate testing, security checks, approval stages, deployment controls, and rollback processes rather than treating each integration as an independent project.
There is still substantial room for maturity. The 2025 Arcati Mainframe Navigator found that only 25% of surveyed organizations described their DevOps maturity as high. Adoption of individual practices also remained uneven, including unit testing at 37%, functional testing at 35%, and automated code deployment at 27%.
Those figures reinforce an important point: introducing APIs does not automatically create a standardized delivery model around them.
What Should API Governance Include?
Governance should follow an API throughout its lifecycle, from initial design through production use and eventual retirement.
A practical approach can establish standards for:
- Ownership: Define who is responsible for the service and underlying business function.
- Access: Control which users, applications, and systems can invoke the API.
- Versioning: Establish how changes are introduced without disrupting existing consumers.
- Testing: Validate integrations, business logic, security, and dependencies before release.
- Documentation: Keep services discoverable so teams can understand and reuse what already exists.
- Monitoring and traceability: Track service activity, errors, dependencies, and operational behavior.
- Exception handling: Define how failed or incomplete workflows are managed.
- Lifecycle management: Determine when services should be reused, updated, deprecated, or retired.
Building these requirements into the development process can help teams maintain consistency without relying on manual governance after every service reaches production.
Why Does Human Oversight Still Matter?
Automation can accelerate build, test, validation, deployment, and monitoring processes. Critical business systems still require clear accountability for changes that could affect production operations.
ISG’s 2026 research highlights governance-first approaches that include human-in-the-loop checkpoints, auditable decision records, quality gates, staged releases, and rollback planning.
Human review can be particularly important when a change affects security permissions, sensitive data, established business rules, financial transactions, or services consumed by multiple downstream applications.
The objective is to establish where automated processes can safely accelerate delivery and where technical or business approval should remain part of the workflow.
Reuse Helps Prevent Integration Sprawl
Governance and DevOps become even more valuable when organizations build integrations for reuse.
A mainframe transaction exposed for one digital application may later be useful to an internal workflow, customer portal, partner service, or automation process. Building a separate integration each time recreates development work and introduces additional components that need to be tested, secured, monitored, and maintained.
Reusable APIs and orchestration patterns give teams a common service to build from.
Adaptive Integration Fabric supports this approach by allowing teams to visually create REST and SOAP interfaces around established applications and coordinate programs, data, rules, transformations, and external services through governed orchestration. Approved integrations can then be reused across applications, partners, workflows, and digital channels rather than rebuilding the same logic for every connection.
How Can Organizations Maintain Control Across Hybrid Environments?
Mainframe applications increasingly operate as part of a broader environment that includes distributed applications, cloud platforms, external services, partners, and digital channels.
That makes consistency across integration points increasingly important.
Adaptive Integration Fabric provides a governed integration layer between established systems and modern services. Its orchestration capabilities can coordinate multi-branch workflows across backend processes, transformations, business rules, data, and external services. Fabric also supports controls including authentication, authorization, validation, monitoring, trace logging, version control, reusable components, and exception handling.
This gives technical teams a structured way to extend core capabilities while maintaining visibility and control over how integrations are designed and operated.
Building a More Sustainable Modernization Model
Sustainable modernization requires more than exposing another transaction or connecting another application.
APIs provide standardized access to trusted business capabilities. DevOps creates repeatable processes for building, testing, and releasing change. Governance establishes the controls around ownership, security, lifecycle management, and reuse. Human review maintains accountability where operational risk requires it.
Adaptive Integration Fabric brings these principles together on the integration side by supporting governed API creation, reusable integration patterns, and complex service orchestration while preserving the established applications and business logic already supporting the enterprise.
When these practices advance together, organizations can build a more repeatable foundation for connecting trusted core capabilities to new applications, services, and workflows while maintaining the operational control enterprise environments require.
Learn more about Adaptive Integration Fabric