Plan

Software development challenges

Code organization problems

Architecture definition

Architectural Pattern

Software development challenges

Expectation

Software development challenges

Requirements volatility

Software development challenges

Market/Stakeholder pressure

Software development challenges

High coupling and low cohesion

Software development challenges

Modification challenges

Software development challenges

Readability

Software development challenges

Lack of QA

Software development challenges

Integration challenges

Code organization problems

Code organization problems

Bad news: it's serious

Good news: it's fixable

Architecture definition

Architecture definition

Grady Booch

Chief Scientist for Software Engineering at IBM

UML co-author

Booch method author

Architecture represents the significant design decisions that shape a system, where significant is measured by cost of change.

wiki

Architecture definition

Martin Fowler

Chief Scientist at ThoughtWorks

«Refactoring: Improving the Design of Existing Code» author

Software architecture is the set of decisions which are both important and hard to change.

wiki, blog, architecture page, architecture definition video

Architecture definition

Juval Lowy

Software architect and the principal of IDesign

Microsoft's Regional Director for the Silicon Valley

If it does not change, there is no block that encapsulates it on architecture diagram.

about, IDesign

Architecture definition

Robert "Uncle Bob" Martin

«Clean Code» author

SOLID principles author

Agile manifesto co-author

Architectures are not (or should not) be about frameworks.

wiki, blog

Architecture definition

Architecture ~ Change

Risk management decisions in anticipation of inevitable change of system's requirements.

Good architecture is resilient to changes.

Good architecture is a result of many educated trade-offs.

Mostly independent of third-party frameworks and libraries.

Good architecture severely reduces the cost (effort) of software development and maintenance.

Architecture definition

It's a pleasure to work with good architecture.

No need to look for things.

Readable and intuitive.

Easy to reason about and modify.

Productive and less stressful.

Architecture definition

Martin Fowler

...the shared understanding that the expert developers have of the system design.

Ralph Johnson

Architecture is about the important stuff. Whatever that is.

Architecture definition

High internal quality leads to faster delivery of new features

Cruft — badly designed, unnecessarily complicated, or unwanted code or software.

Architecture definition

Attention to internal quality pays off in weeks not months.

Architectural Pattern

An architectural pattern is a general, reusable solution to a commonly occurring problem in software architecture within a given context.

Architectural Pattern

An architectural pattern is a general, reusable solution to a commonly occurring problem in software architecture within a given context.

Usually independent of implementation details.

Architectural Pattern

An architectural pattern is a general, reusable solution to a commonly occurring problem in software architecture within a given context.

Usually independent of implementation details.

It's a bit more common thing than design patterns, not as detailed as them.

Architectural Pattern

An architectural pattern is a general, reusable solution to a commonly occurring problem in software architecture within a given context.

Usually independent of implementation details.

It's a bit more common thing than design patterns, not as detailed as them.

Architectural pattern ≠ architecture.

Architectural Pattern

An architectural pattern is a general, reusable solution to a commonly occurring problem in software architecture within a given context.

Usually independent of implementation details.

It's a bit more common thing than design patterns, not as detailed as them.

Architectural pattern ≠ architecture.

Examples

• Presentation data layering: MVx
• Notifications: publish-subscribe architecture
• State change management: event-driven architecture
• DI architectural pattern