Software architect: the strategist behind the scenes

Architectural principles serve as a foundation for decision-making in system design. They provide a set of values and standards that ensure alignment with organizational goals and best practices, guiding architects through the complexities of system architecture.

The general and well-known system design principles are:

• Separation of responsibilities
• Modularity
• Loose coupling
• High cohesion

The 5 SOLID principles were formulated for object-orientated software development:

• Single Responsibility: Each class should have exactly one responsibility and not take care of several tasks.
• Open-Closed: A class should be open for extensions, but closed for modification. This makes it possible to add new functionality without changing the existing code.
• Liskov Substitution: Subtypes should be substitutable for their base types: It should be possible to use a subclass instead of the superclass without affecting the functional context.
• Interface Segregation: Clients should not be forced to implement interfaces they don’t use: An interface should focus on a specific group of classes that implement it.
• Dependency Inversion: High-level modules should not depend on low-level modules, but both should depend on abstractions: A class should not be directly dependent on another class, but should communicate via an interface.

Keeping things simple is a big challenge, especially with complex systems. It is easy to get lost in the details and develop overly complicated solutions. The reminds us that the simplest solution is often the best: keep it simple stupid.

Mastering these principles enables architects to make informed decisions throughout the software development lifecycle.

Architecture patterns are software systems. They provide proven solutions to recurring architectural problems. Design principles help us to implement these patterns effectively. A broad understanding of different architectural patterns and styles is essential for architects. This knowledge helps not only in building the software system, but also in navigating through the various phases of the software development life cycle, such as requirements gathering, analysis, design, implementation, testing, deployment and maintenance.

The use of Architecture Decision Records (ADRs) is a valuable practice for documenting architectural decisions. This process promotes transparency and systematic decision-making, allowing architects to review and revise their choices as the software evolves.

Architects must also focus on scalability and performance, ensuring that systems can adapt to varying loads and maintain functionality. As projects grow, continuous evaluation of feedback regarding an application’s performance is necessary to ascertain the impact of architectural choices on user experience and system efficiency.

A thorough knowledge of cloud computing is indispensable for modern software architects. Familiarity with platforms such as Amazon Web Services (AWS), Microsoft Azure, and Google Cloud Platform (GCP) enables architects to design cloud-native applications that leverage serverless computing and ensure . Tools like Infrastructure as Code (IaC) further enhance the architect's ability to manage and provision infrastructure efficiently.

The security of a software system is one of the most important quality characteristics. Therefore, it should be integrated into the design process from the beginning instead of being considered later (security by design).

The CIA Triad is a globally recognized security model that guides IT security policy within an organization and serves as a universal tool for secure design. It defines three key objectives for protecting data and systems:

• Confidentiality: Data should be kept private and protected from unauthorized access.
• Integrity: Data should remain unchanged and unaltered to ensure its validity and reliability.
• Availability: Data and systems should be accessible and available at all times and for legitimate purposes.

Thread modeling is a structured process for identifying and prioritizing potential threats and vulnerabilities in software applications. It involves analyzing attack vectors, potential attackers, their motivations, and the methods they use to exploit vulnerabilities. This process helps architects understand potential threats and take appropriate security measures.

Security is always viewed as a "cross-cutting concern" that affects multiple areas of the system. This means that security measures should not be limited to individual components, but should apply to the entire system.

Modeling and diagramming tools play a crucial role in visualizing system architecture. Tools like UML (Unified Modeling Language) and BPMN (Business Process Model and Notation) help architects create clear representations of their designs, which enhances communication with stakeholders and team members. These visual aids are indispensable for illustrating complex systems in a more understandable format, thus allowing team members to focus on specific aspects relevant to their work.

Version control systems, such as Git, are fundamental in software development and equally important in software architecture. They enable architects to manage changes, collaborate with others, and track the evolution of architectural designs over time. By facilitating the management of concurrent modifications, version control helps prevent conflicts and inconsistencies, ensuring that all alterations to the architecture are coordinated and documented appropriately.

API design tools, including Swagger and OpenAPI, are utilized to document and design APIs that are consistent and clear, promoting seamless interaction between system components. These tools assist in defining how different parts of a software system communicate, which is critical for integration and functionality.

When designing the API, consider the possibility of versioning: new functionality can co-exist with existing methods, and users of the API can access them with different client versions.

In addition to modeling tools, architects employ design and analysis tools to develop architectural blueprints and assess performance metrics. These tools assist in making strategic decisions regarding design patterns, scalability, and potential bottlenecks, contributing to the overall robustness of the architecture.

An iterative approach is essential in the context of using architectural tools. This practice involves utilizing these tools throughout of the project lifecycle - not just during initial design - to continuously update and refine the architecture as project requirements evolve. This flexibility allows architects to adapt to changes, incorporate feedback, and ensure that the architecture remains aligned with business objectives.

Integrating architectural tools across the development lifecycle promotes enhanced communication and collaboration among team members and stakeholders. This also ensures that the actual status and the documentation are consistent. Visual representations created by these tools help convey complex ideas more effectively, leading to improved design quality and alignment within the development team.