Business Logic Development Pitfalls

In previous chapters, we defined business logic very narrowly and very deliberately: business logic decides which state a business process enters next.

This definition is much more limited than what is commonly called “business logic” in everyday software development practice.

The most common business logic pitfall is giving it responsibilities that belong to other logic layers.

The Common Misconception

In many software systems, the term business logic is used as a catch-all label. Any code that does not clearly belong to the user interface or the database is often placed into a “business logic layer”.

As a result, business logic is frequently expected to:

• Transform or calculate data
• Control how data is accessed or updated
• Coordinate interactions between business objects

While these activities are important, they are not business logic in the sense used in this book.

What Goes Wrong

When business logic absorbs responsibilities from other layers, several problems emerge:

• Business logic becomes large, complex, and hard to reason about.
• Decision-making code is mixed with data manipulation code.
• Changes in data structure force changes in business decisions.
• The true decision points of the process become difficult to identify.

Over time, the “business logic layer” turns into a general-purpose container for everything that does not fit elsewhere.

The Correct Role of Business Logic

In Business Process Programming, business logic has a single, focused responsibility.

Business logic evaluates the outcome of a transition and selects the next state of the business process according to business rules.

It does not:

• Access data stores
• Transform raw data
• Control presentation flow

Those responsibilities belong to data access logic, data processing logic, and state logic respectively.

Why This Pitfall Is So Common

This pitfall appears because many architectures are not built around explicit business process states.

When states and transitions are not clearly modeled, decision-making becomes scattered across the system, and business logic naturally expands to fill the gaps.

By keeping business logic focused on state selection only, the structure of the business process remains visible, testable, and adaptable to change.

Table of Content Software Development Pitfalls Previous: Presentation Logic Development Pitfalls Next: Git Strategy Pitfalls and an Environment-Centric Solution

 

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Business Process Programming in .Net
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