Setting the stage: Why abstraction matters

In today’s rapidly evolving engineering landscape, the ability to structure tasks effectively is more than a technical skill; it is a cornerstone of clear communication and successful project delivery. Structuring development tasks was a popular topic explored in the early ‘90s by authors such as Robert Martin, Bertrand Meyer, and others – but the foundation was laid decades prior by Dr. Barbara Liskov’s team. The discovery of abstract classes and their use cases were some of the main contributions from that period. The aim of this blog is to provide a foundation that introduces the concept of abstract classes and illustrates their practical value for engineers at every level.

Building blocks: Objects, classes, and abstraction

The foundation starts with objects – or collections of methods and variables, and classes – which serve as templates for creating objects. Abstract classes go further, acting as templates for creating classes. They define patterns that classes must follow, bringing consistency and reliability to codebases.

Precision and flexibility: The benefits of abstraction

Abstract classes offer three major advantages: precision, flexibility, and maintainability. Precision comes from defining only what a consuming class needs to know, reducing unnecessary dependencies. Flexibility is achieved through substitutability, allowing components to be swapped easily. Maintainability follows, as code becomes easier to update and scale.

Interface separation: Keeping code lean

A key principle is the separation of concerns through interface separation. By ensuring classes are only loosely coupled to what they require, developers can limit the scope of a code section’s responsibility. For example, if a button class can rely on the presence of an abstract listener rather than a concrete service, then the button need only be concerned with the API layer of the abstract listener. This approach leads to cleaner and more precise code.

Open-closed and single responsibility: Designing for change

The open-closed principle encourages systems that are open for extension but closed for modification. New features can be added through abstractions without altering tested code, minimizing risk. The single responsibility principle further supports scalability, as each component is responsible for its own implementation and can be maintained independently.

Applying abstractions to AI and teamwork

These principles are especially relevant as teams increasingly collaborate with AI agents. Breaking projects into subtasks and linking them with abstract classes enables concurrent development and independent task management. When everything is loosely coupled together, any single thing can be developed independently. This strategy leverages AI’s strengths, allowing for efficient, flexible workflows across human and AI teams.

Conclusion: Elevating engineering through abstraction

Abstract classes and related design principles like interface separation, substitutability, open-closed, and single responsibility form the backbone of precise, flexible, and maintainable code. As engineering teams embrace agentic coding, these concepts empower developers to manage projects more effectively and collaborate across team boundaries. Mastering abstraction strengthens both technical skills and the ability to lead in a digital world.

For this blog, a special acknowledgment is due to Dr. Barbara Liskov, Institute Professor at MIT, whose pioneering work on data abstraction and abstract classes has shaped decades of software engineering. Learn more: https://dl.acm.org/doi/10.1145/942572.807045

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