When we learned that engineers were losing hours building our C++ codebase, we jumped into investigating the root cause. Here’s how we cut build tim

Speeding up C++ build times

submited by

Style Pass

2024-04-27 10:00:04

When we learned that engineers were losing hours building our C++ codebase, we jumped into investigating the root cause. Here’s how we cut build times in half and shipped a solution for scale.

If you’ve worked with C++ projects, you’re probably all too familiar with the perennial issue of slow build times. They are a major productivity killer, leaving developers stuck in a frustrating cycle of wait, debug, and rebuild. In 2023, build times at Figma were increasing at a disproportionate rate: While the codebase grew by just 10% in a 12-month period, build times had increased by a whopping 50%. It’s no surprise that in our annual internal developer survey, C++ build times were a top pain point. After trying a few stopgap solutions—like purchasing M1 Maxs for our team—build times gradually reverted to their original pace; Ccache and remote caching weren’t enough either. We needed to take more drastic measures, quickly.

Header files contain function declarations, definitions of classes, or constant values that can be used across multiple source files. Header files are included at the beginning of a source file using the #include directive, allowing the compiler to reference the contents during the compilation process.