Measuring code quality might sound complex, but according to BonCode CEO, Jan Willem Klerkx, it’s the easy part of monitoring maintainability. Tools can calculate metrics like module size, duplication, or complexity without much difficulty. The real challenge lies elsewhere: translating those numbers into meaningful insights for both technical and non-technical people across the organization. Here’s why and how we do it.
Why we use a standardized ‘maintainability’ score
“Different audiences in your company need different data,” explains Jan Willem. “You don’t want to bother someone on the board of a large organization with breaches of detailed coding standards. And you don’t want to give software engineers the metrics for a whole software portfolio that they’re not working on.”
That’s why BonCode’s approach is built around targeted insights. Engineers need detailed, actionable feedback on their craft. CTOs and managers need trends and risk indicators to guide decisions. And board-level stakeholders need a simple, comprehensible picture of whether a software portfolio is in good shape or heading for trouble.
That’s why a standardized maintainability score is a valuable tool.
How do we score your maintainability?
Our maintainability score is a single aggregated number between 0 and 100. Is it a holy number? No. Is it always 100% accurate? No. Is it oversimplified? Yes. So why’s it so important? Because it empowers your decision-making on multiple levels.
Think of it like a body mass index. BMI is a simple guide to whether you’re the correct weight for your height, and therefore an early indicator of your propensity to certain health risks. Everyone knows it’s simplistic, but it gives you a baseline, a way to spot risk and see trends over time.
That’s exactly like our maintainability score, which combines three key components:
- Volume (25%) – How large and duplicated is the codebase? Smaller modules and less duplication make maintenance easier.
- Code Quality (50%) – How well-crafted is the code? Factors like unit size, complexity, and coupling between modules determine how understandable it is.
- Structure (25%) – How logically organized is the system? Clear architecture, like neat wiring in a car, gives engineers the confidence to make changes without fear of breaking something.
How to use maintainability score in practice
The structure of a codebase often has the biggest impact on whether teams feel confident making changes. A clear structure reduces fear and accelerates development. Jan Willem likens poor architecture to tangled car wiring: “If it’s nicely color-coded, I know what I’m working on. But if it’s all gray spaghetti, I’m terrified of touching it.”
A maintainability score is measured continuously, often daily or weekly, but reported differently depending on the audience. Engineers use it in sprint meetings to see if their changes are improving maintainability. Senior leaders review it quarterly, spotting long-term trends that indicate risk or erosion.
Crucially, it helps bridge conversations between business and technical teams. “What you typically see,” says Jan Willem, “is the business pushing for more features. Technical people want to please, so they keep building, but quality erodes.”
Our data helps engineers push back. They can show the business impact. For example, a feature that now takes a month instead of a week because maintainability dropped. That’s when management agrees to freeze requirements and refactor.”
Hitting the maintainability sweet spot
The goal isn’t perfection. BonCode categorizes systems from not maintainable to gold-plated, but Jan Willem argues the optimal range is simply good: “The sweet spot is between 70 and 80. Just like school grades: you don’t need a perfect 10, but you don’t want to slip below a 7 either.”
At BonCode, the maintainability score isn’t about replacing human judgment but empowering it. Our score creates a common language for software engineers, managers, and executives to align on quality.
If you’re curious about how maintainability scoring could help your organization manage risk, reduce costs, and build more resilient software, follow BonCode on LinkedIn.
