⚡ Bolt: [performance improvement] Optimize fs.readFileSync by providing encoding

[vishnu-madhavan-git]

💡 What

Replaced instances of fs.readFileSync(filepath).toString() with fs.readFileSync(filepath, 'utf8') across multiple files in the @expo/cli, @expo/config-plugins, expo-brownfield, and pod-install packages.

🎯 Why

When fs.readFileSync is called without an encoding argument, it returns a raw Buffer object which contains the entire contents of the file in memory. Calling .toString() on this buffer then allocates a new string in memory and copies the data into it, leaving the original Buffer to be garbage collected. Providing the 'utf8' encoding argument directly to fs.readFileSync bypasses this intermediate Buffer allocation, saving memory and slightly improving execution time.

📊 Impact

Micro-optimization: Reduces peak memory usage during file reads and saves garbage collection overhead. Since this is used in file template readings and config generation processes which happen across many files concurrently or synchronously, this could provide a tiny overall performance boost without sacrificing readability.

🔬 Measurement

Run yarn --cwd packages/<package-name> jest or test manually by benchmarking memory profiling tools while building/reading configurations. The logic is functionally identical so no breaking changes are introduced.

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PR created automatically by Jules for task 10099740639748954076 started by @vishnu-madhavan-git

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Project	Deployment	Actions	Updated (UTC)
v1-nexlyn	Ready	Preview, Comment	Apr 16, 2026 8:07am

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