ADR-011: KISS Principle (Keep It Simple, Stupid)
Status: Accepted
Date: 2025-07-16
Authors: Piotr Brzozowski
Reviewers: Piotr Brzozowski
The KISS (Keep It Simple, Stupid) principle is adopted as a guiding design philosophy for all Entirius development. This promotes simplicity in code design, architecture decisions, and implementation approaches while balancing functionality requirements with maintainability.
- Default to simple: Choose the simplest solution that meets requirements
- Refactor complex code: Break down complex functions into smaller, focused components
- Clear naming: Use descriptive, self-explanatory variable and function names
- Minimal dependencies: Avoid unnecessary libraries or frameworks
- Readable code: Write code that explains itself without extensive comments
Complex solutions are acceptable when:
- Business requirements explicitly demand the complexity
- Performance requirements cannot be met with simpler approaches
- Regulatory or security requirements necessitate additional complexity
- Long-term maintainability benefits outweigh short-term simplicity
- Is this the simplest solution that works?
- Can this be broken into smaller, more focused functions?
- Are the variable and function names clear and descriptive?
- Is the logic flow easy to follow?
- Would a new developer understand this code quickly?
As the Entirius platform grows in complexity with its modular monolith architecture, there is a constant need to balance feature richness with maintainability. The development team has observed instances where solutions have become unnecessarily complex, leading to:
- Increased development time for new features
- Higher maintenance costs
- Steeper learning curve for new team members
- More bugs and edge cases
- Reduced system reliability
The KISS principle (Keep It Simple, Stupid) is a design philosophy that emphasizes simplicity in design and implementation. This principle is particularly relevant for Entirius as it helps maintain code quality while scaling the platform.
- Description: Enforce rigorous simplicity standards across all code, rejecting any solution that isn’t the simplest possible
- Pros:
- Maximum code simplicity
- Fastest development cycles
- Easiest debugging and maintenance
- Cons:
- May limit architectural flexibility
- Could lead to oversimplified solutions that don’t meet complex requirements
- Might require frequent refactoring as needs evolve
- Impact on system: Significant refactoring of existing complex components
- Description: Apply KISS principle as a guiding philosophy while allowing complexity when justified by business requirements
- Pros:
- Maintains simplicity as default approach
- Allows for necessary complexity when requirements demand it
- Promotes thoughtful design decisions
- Balances maintainability with functionality
- Cons:
- Requires judgment calls on when complexity is justified
- May lead to inconsistent application across teams
- Impact on system: Gradual simplification of existing code where possible
- Description: Establish KISS as a recommended practice without enforcement mechanisms
- Pros:
- No disruption to existing development workflows
- Flexible application based on developer judgment
- Cons:
- May not effectively address existing complexity issues
- Inconsistent adoption across the team
- Limited impact on code quality improvement
- Impact on system: Minimal changes to existing architecture
Chosen option: Balanced KISS Approach
Key decision factors:
- Maintainability focus: Simple code is easier to understand, debug, and modify, supporting long-term project sustainability
- Developer onboarding: Clear, simple code reduces learning curve for new team members and improves productivity
- Quality improvement: Simpler solutions typically have fewer bugs and edge cases than complex alternatives
- Risk analysis: Over-simplification risks are balanced by clear criteria for justified complexity
- Business impact: Faster development cycles and lower maintenance costs through reduced code complexity
- Compatibility: KISS principles complement existing architecture decisions and development practices