Glimpse of Google: Readability

Welcome to Glimpse of Google, a blog series written by a former Google software engineer, offering a firsthand look into the inner workings of one of the most transformative companies of our time. This series will uncover how Google operates from an engineering standpoint and explore the broader company culture, guiding principles, and unique approaches that make it a powerhouse in technology. Whether you're an engineer, a tech enthusiast, or simply curious, Glimpse of Google provides insider insights into what makes Google tick.

The concept of readability goes far beyond simple code formatting and basic syntax. It's about understanding the unique quirks, idioms, and best practices of each programming language used within the company, ensuring code is written in a way that maximizes efficiency, clarity, and maintainability. While every language has its universally agreed-upon syntax, true fluency lies in writing code that's optimized for its specific strengths and nuances. This is where readability approvers play a crucial role.

Readability approvers are experienced engineers who have proven their mastery of a specific language. They are more than just expert programmers; they are the people who know inside and out the code style and patterns for the specific language (within Google - the external code style of a language is not all the times the same as the Google internal one). This dedication earns them the ability to review changes and ensure they adhere to the highest standards of code quality specific to that language. An engineer can become a readability approver by consistently demonstrating this in-depth knowledge during code reviews and by applying proven best practices in their own work.

The readability process works hand-in-hand with the broader code review system. Every significant code change at Google (called a "change list" internally) requires approval from two sources: a peer reviewer assessing overall functionality and logic, and a readability approver specifically scrutinizing the language-specific nuances of the code. This two-pronged approach ensures that changes not only pass the automated linting checks for basic formatting but also receive human scrutiny from experts who understand how to write code that's both correct and elegant within a specific language.

Beyond just being gatekeepers, readability approvers actively raise the bar for everyone on the team. They become mentors and advisors for less experienced engineers working with a particular language. This fosters a culture of knowledge sharing and collaboration, ensuring that newcomers have access to guidance and can learn the optimal ways to write clear, maintainable code to that specific language within Google. The benefits extend beyond individuals – when knowledge of language-specific best practices becomes widespread throughout a team, it speeds up development by preventing common pitfalls and reducing the need for extensive rewrites down the line.

The readability process isn't about rigid rules; it's a dynamic system for continuous learning and improvement. With language champions embedded across teams, Google ensures that expert knowledge is within reach whenever an engineer tackles a new area of the codebase or picks up a new programming language. This organic dissemination of best practices ultimately leads to a more cohesive codebase and a smoother overall development experience.

By taking code quality seriously and investing in fostering language-specific expertise, they ensure the work done today remains a valuable asset for many years to come.