Quick Start with Structure101: Tools and TechniquesStructure101 is a set of tools and practices designed to help software teams visualize, control, and improve the architecture of complex codebases. It focuses on making structural issues visible, enforcing architectural rules, and guiding incremental improvements so systems remain maintainable as they grow. This article gives a practical quick start: what Structure101 does, how it fits into a development workflow, core techniques, and hands-on tips for getting value quickly.
What Structure101 Does and Why It Matters
Structure101 helps teams manage the architecture of their code by providing:
- Visualization of structure: interactive diagrams that reveal modules, packages, and their dependencies.
- Architecture rules and constraints: define allowed dependencies, layering, and stable/unstable zones to prevent erosion.
- Measurement and metrics: quantify architectural debt with metrics such as cycles, dependency strength, and layering violations.
- Incremental refactoring guidance: prioritize and track work to reduce cycles and simplify the structure over time.
Maintaining a healthy architecture prevents problems like slow builds, brittle code, and long onboarding times. Structure101 makes architectural health visible and actionable.
Key Concepts
- Modules and components: logical groupings of code (packages, jars, projects) you can analyze.
- Dependency graphs: directed graphs showing which modules depend on which.
- Cycles: groups of modules that depend on each other, creating tight coupling.
- Allowed/forbidden dependencies: rules that define permitted relationships.
- Layers and zones: architectural organization to enforce direction and stability.
Getting Started: Installation & Setup
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Obtain Structure101:
- Structure101 is available as both a desktop application and server offering. Choose the edition that fits your team size and CI/CD needs.
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Connect to your codebase:
- Point Structure101 to your build outputs (compiled classes, jars) or source code. For Java, the tool reads package/jar/class dependencies; for C/C++ and other ecosystems, use available import/parsing options or exported dependency reports.
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Create a model:
- Import the dependency graph and let Structure101 generate an initial model. This model becomes your working map of the system’s structure.
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Define modules:
- Group packages/classes into higher-level modules or components. Use naming that matches team responsibility or architectural intent.
Visualizing and Exploring Structure
Use the interactive diagrams to:
- Zoom between high-level components and low-level packages.
- Identify high-dependency hubs (modules with many incoming edges).
- Find cycles (SCCs—strongly connected components) that indicate refactoring opportunities.
- View dependency heatmaps and layering violations.
Tip: Start at a high level to identify candidate problematic modules, then drill down to see which packages/classes create the problems.
Setting Rules and Architectural Constraints
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Define allowed dependencies:
- Create a ruleset that specifies which modules may depend on which. This can be layered (e.g., UI -> Service -> Persistence) or ownership-based.
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Use forbidden dependencies to prevent architectural regression:
- Mark dependencies that must not appear (e.g., lower-level modules referencing higher-level ones).
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Enforce cycles restrictions:
- Set thresholds for allowed cycle size; mark large SCCs as areas needing refactor.
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Save rules as policies:
- Apply policies per branch, team, or release to manage architectural evolution.
Techniques for Improving Structure
- Break cycles by introducing interfaces/abstractions, dependency inversion, or by extracting shared functionality.
- Reduce coupling by moving utility/shared code into clearly designated stable modules.
- Apply the Stable Dependencies Principle: keep stable, widely used modules small and well-designed.
- Use the Common Closure Principle to group classes that change for the same reason into the same module.
- Incrementally refactor: address the highest-impact cycles or violations first; small, verifiable changes reduce risk.
Integrating with CI/CD and Workflows
- Add Structure101 checks to CI builds to fail or warn when rules are violated.
- Use automated reports to track architectural debt over time.
- Make architectural rules part of pull request reviews: include Structure101 diff artifacts or rule-check summaries.
- Assign owners for modules so architectural decisions have clear responsibility.
Prioritizing Work: What to Fix First
- Target modules with large fan-in or fan-out—these are higher risk.
- Fix cycles that block team independence or prevent parallel development.
- Address layering violations that allow unauthorized access to internals.
- Prioritize changes that reduce compilation or test times.
Common Pitfalls and How to Avoid Them
- Overly strict rules too early: start with permissive rules and tighten as the team gains discipline.
- Trying to perfect the model before taking action: keep the model pragmatic and evolve it.
- Ignoring developer ergonomics: ensure rules integrate smoothly into the dev workflow to avoid resistance.
Example Workflow (Java project)
- Import compiled artifacts (jars/classes) into Structure101.
- Generate the initial map and identify top 5 problematic modules (by cycles, fan-in).
- Define a simple layering rule: API -> Service -> Persistence.
- Run a CI job that exports a Structure101 report and fails if new forbidden dependencies are introduced.
- Create small refactor tickets to extract interfaces and break cycles; run Structure101 locally to validate.
Metrics to Watch
- Number and size of cycles (SCCs).
- Number of rule violations over time.
- Module fan-in/fan-out distribution.
- Average dependency distance (how far upper layers reach into lower layers).
Final Tips
- Treat Structure101 as part of the “architecture as code” toolset: keep rules in version control.
- Use visuals in architecture reviews to align teams.
- Iterate: incremental improvements compound into large structural gains.
If you want, I can tailor this article to a specific language (Java, .NET, C++) or expand any section into step-by-step tutorials or CI examples.
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