Ninja

Purpose

Guide agents through Ninja as a build executor: diagnosing failures, controlling parallelism, generating from CMake, and understanding the .ninja file format when needed.

Triggers

• "Ninja is failing — how do I get more output?"
• "How do I use Ninja with CMake?"
• "How many parallel jobs does Ninja use?"
• "How do I add a custom build step in Ninja?"
• "What is a build.ninja file?"

Workflow

1. Ninja as a CMake generator

The most common use of Ninja is as the build executor for CMake: