Bun Foreign Function Interface (FFI) FAQs

Question 1

What is Bun FFI used for?

Accepted Answer

Bun FFI (Foreign Function Interface) allows you to call functions from native shared libraries (written in C, C++, Rust, etc.) directly from your Bun JavaScript or TypeScript code without needing to write a complex N-API wrapper.

Question 2

Does this skill help with cross-platform library loading?

Accepted Answer

Yes, it provides patterns using Bun's 'suffix' utility to automatically handle different file extensions for shared libraries across macOS (.dylib), Linux (.so), and Windows (.dll).

Question 3

Can I use JavaScript functions as callbacks in native code?

Accepted Answer

Yes, the skill includes specific implementation patterns for the 'callback' function in bun:ffi, allowing native C code to execute JavaScript logic.

Question 4

Is Bun FFI faster than Node-API?

Accepted Answer

Generally, yes. Bun's FFI is designed for zero-overhead or near-zero-overhead calls, making it significantly faster than traditional native abstractions in other runtimes.

Question 5

How does Bun FFI handle memory management?

Accepted Answer

Bun FFI allows you to work with pointers and ArrayBuffers. While JS memory is garbage collected, the skill provides patterns for manually freeing memory allocated by C libraries to prevent leaks.

Bun Foreign Function Interface (FFI)

Key Features

Use Cases

Bun Foreign Function Interface (FFI)

Key Features

Use Cases