The Problem: As Codebases Grow, Familiarity Fades

The math is surprising yet undeniable. Research shows that once a codebase expands beyond 1 million lines, productivity per developer drops nearly 50%. For fast-scaling organizations, this drop in efficiency can feel like a “productivity tax,” resulting in the need for additional developers simply to maintain the same output as before. But what drives this loss in productivity?

The answer lies in what we call Lost Familiarity. Every developer holds invaluable knowledge about the code they work on, which enables them to make modifications and improvements efficiently. However, as developers leave or shift roles, their familiarity with the code goes with them, leaving gaps that can take months to fill.

“Changing a few lines of code may take someone familiar with the code a few minutes, whereas another developer may take a week instead,” says Jackson Lawrence, Team Lead at Cin7.

The impact of these knowledge gaps compounds over time, slowing down cycles, delaying new features, and making collaboration harder.

‍

The Insight: Code Knowledge as a Foundation for Productivity

Through their experience, DevRamp’s founders realized that code familiarity—knowing who understands what within the codebase—is directly tied to productivity. Teams that actively retain and share code knowledge work faster, make fewer errors, and collaborate more effectively. However, in most teams, code familiarity is an untracked asset that’s lost as projects evolve.

This realization led to a central insight: code familiarity is more than just a resource—it’s an essential asset that protects against productivity loss and helps teams build sustainably.

‍

How Code Familiarity Builds Resilient Development Teams

Recognizing the importance of code familiarity has implications beyond productivity alone. Here are some ways code familiarity strengthens teams and improves development outcomes:

• Accelerates Onboarding: New developers who can access shared knowledge integrate faster and contribute sooner, avoiding months of ramp-up time.
• Supports Collaboration: Teams can easily identify who knows what, making it easier to ask the right questions and solve issues quickly.
• Reduces Key Person Risk: With code familiarity widely shared, the risk of losing essential knowledge when someone leaves is minimized, ensuring continuity.
• Minimizes Technical Debt: When developers understand the history and context of code, they can improve it thoughtfully, preventing repetitive refactoring and costly rewrites.

‍

Looking Forward: Building a Culture of Code Knowledge

The insight that code familiarity drives productivity is a fundamental shift in how we approach development. Instead of throwing more and more valuable resources at problems, teams can build resilient codebases where knowledge is an asset that grows and evolves with the team.

Imagine a development environment where code familiarity is actively cultivated, making productivity scalable and key person risk a thing of the past. By prioritizing code knowledge, development teams can reclaim efficiency, maintain continuity, and confidently move forward—even as they grow.

‍

¹ Source: Steve McConnell - Software Estimation: Demystifying the Black Art (Developer Best Practices)

‍