Engineering is a craft. Writing code isn’t just about functionality—it’s about creating something maintainable, efficient, and scalable. Yet, for years, software teams have struggled with an age-old dilemma: 

How do we measure the quality of our code? 

Some say, “You know clean code when you see it.” Others rely on instinct. But here’s the problem: gut feelings don’t scale. Codebases grow, engineers come and go, and what seemed like “good code” one day can become a cautionary tale the next. 

At Hubtel’s Code Quality Team, we decided to tackle this head-on. We needed something more than intuition—something measurable, actionable, and scalable. And so, we built the Code Confidence Index (CCI)—not just to measure code quality, but to improve it. 

READ ALSO: From Snail Mail to Warp Speed: How Hubtel Rocketed Its Product Delivery 

Why Code Quality Matters (And Why We’re Tired of Fighting Bad Code) 

Let’s not pretend: bad code is a productivity sinkhole. 

• It slows down development cycles. 

• It makes debugging feel like archaeology. 

• It increases technical debt faster than a high-interest loan. 

On the other hand, high-quality code accelerates everything. Developers ship features faster, fixes are easier, and scaling is a joy rather than a death march. 

But there’s a catch: quality must be measurable. If we can’t quantify it, we can’t improve it. That’s where CCI steps in. 

Introducing the Code Confidence Index (CCI): The Metric That Changed Everything 

Imagine trying to lose weight without a scale. You might feel healthier, but without numbers, how do you know you’re making progress? 

That was our approach to code quality—until we built CCI. 

CCI is a single, actionable score that evaluates the overall health of a codebase. Instead of vague statements like “This module feels messy,” we get hard data: 

✅ Test Coverage: Are we testing enough of our code? 

✅ Bugs & Vulnerabilities: How many issues are creeping into production? 

✅ Code Complexity & Smells: How maintainable is our architecture? 

✅ Duplications & Framework Hygiene: Are we following best practices? 

CCI doesn’t just diagnose issues—it guides improvement. A repository with a score of 58/100? It tells us exactly where to focus. A score of 80/100? It confirms our hard work is paying off. 

And it’s not just theoretical. We tested it, and the results were game-changing. 

Case Study: The Repository That Went From 58 to 80 

To see if CCI really worked, we applied it to a backend repository with a score of 58/100. 

The Diagnosis: A Codebase in Trouble 

Breaking down the numbers, we saw the problems clearly: 

• Test Coverage: 25% (far too low) 

• Bugs: 12 major issues 

• Security Vulnerabilities: 8 flagged risks 

• Code Smells: 250 problematic patterns 

• Cognitive Complexity: 2500 (dense, difficult-to-read code) 

• Duplicated Lines Density: 12% 

This wasn’t just an abstract number—this was friction in every commit, every merge, every deployment. 

The Plan: Smart, Targeted Fixes 

Rather than an endless refactor, we took a strategic three-phase approach: 

Phase 1: Boosting Test Coverage (2 Weeks) 

• Added unit tests for core logic 

• Implemented integration tests for key workflows 

• Increased coverage from 25% to 50% 

Phase 2: Fixing Bugs & Security Issues (1 Week) 

• Addressed 7 critical bugs 

• Fixed 5 high-priority security vulnerabilities 

• Reduced bug count from 12 to 5, vulnerabilities from 8 to 3 

Phase 3: Cleaning Up the Code (2 Weeks) 

• Refactored complex methods 

• Removed redundant, duplicated code 

• Reduced code smells from 250 to 100 

The Outcome: A Healthier, More Maintainable Codebase 

After just a few weeks, we saw dramatic improvements: 

• Test Coverage: 50% (+100% increase) 

• Bugs: Reduced from 12 to 5 

• Vulnerabilities: Down from 8 to 3 

• Code Smells: Dropped from 250 to 100 

• Cognitive Complexity: Reduced by 60% 

• Duplicated Lines Density: Cut in half 

Final CCI score: 80.3—a 38% increase. 

Beyond the numbers, the real impact was felt in daily development. PRs merged faster, debugging was smoother, and the once-dreaded repo became far easier to work with. 
 
Sustained Improvement Without Development Disruptions 

One of the greatest advantages of integrating CCI into our workflow is that it allows us to improve code quality without derailing development cycles. Traditionally, code quality initiatives often mean halting sprints for refactoring, leading to delays and frustrated teams. With CCI, quality improvement becomes a continuous process, not a roadblock. Engineers make incremental enhancements alongside feature development, ensuring that we build, ship, and refine without grinding productivity to a halt. 

How CCI is Reshaping Our Engineering Culture 

This wasn’t just about fixing one repository. CCI is changing the way we think about code quality. 

1. Code Quality Sessions That Matter 

We turned code reviews into structured quality sessions, where senior engineers review repositories, provide insights, and mentor teammates. Instead of nitpicking syntax, we now discuss real structural improvements. 

2. Data-Driven, Not Opinion-Driven Engineering 

Discussions about code quality are no longer subjective debates. Instead of “This feels off,” we now say: 

• “Our test coverage needs to improve by 15%.” 

• “We have too much cognitive complexity in this module—let’s refactor.” 

3. A Culture of Continuous Improvement 

Rather than vague aspirations to “write cleaner code,” teams now have clear targets. Engineers actively track their CCI scores, making quality improvement a habit, not an afterthought. 

READ ALSO: Scaling an Engineering Team from 16 to Over 100 in Less Than 4 Years: Hubtel’s Journey, A Tale of Growth, Innovation, and a Whole Lot of Coffee 

Beyond the Score: What This Means for Software Engineering 

CCI is more than a metric. It’s a philosophy. 

• It shifts quality from subjectivity to objectivity. 

• It turns code maintenance from a chore to a structured process. 

• It creates a feedback loop where engineers can see their progress. 

Software engineering isn’t just about building features. It’s about building sustainable systems that stand the test of time. And for that, code quality can’t be left to gut feelings. It needs to be measured, tracked, and continuously improved. 

Final Thoughts: Measuring What Matters 

For years, developers have debated what makes good code. With CCI, we no longer need to guess. We have the numbers, we have the process, and we have the results. 

So the next time someone says, “You know clean code when you see it,” ask them this: 

“Do you have the data to prove it?” 

Because at Hubtel, we do.