@bun-win32/version

@bun-win32/version

Zero-dependency, zero-overhead Win32 Version bindings for Bun on Windows.

Overview

@bun-win32/version exposes the version.dll exports using Bun's FFI. It provides a single class, Version, which lazily binds native symbols on first use. You can optionally preload a subset or all symbols up-front via Preload().

The bindings are strongly typed for a smooth DX in TypeScript.

Features

• Bun-first ergonomics on Windows 10/11.
• Direct FFI to version.dll (file version resources, translation tables, and installer helpers).
• In-source docs in structs/Version.ts with links to Microsoft Docs.
• Lazy binding on first call; optional eager preload (Version.Preload()).
• No wrapper overhead; calls map 1:1 to native APIs.
• Strongly-typed Win32 aliases (see types/Version.ts).

Requirements

• Bun runtime
• Windows 10 or later

Installation

bun add @bun-win32/version

Quick Start

import { read, toArrayBuffer } from 'bun:ffi';

import Version from '@bun-win32/version';

Version.Preload(['GetFileVersionInfoSizeW', 'GetFileVersionInfoW', 'VerQueryValueW']);

const filePath = Buffer.from(process.execPath + '\0', 'utf16le');
const versionInfoSize = Version.GetFileVersionInfoSizeW(filePath.ptr, null);

if (versionInfoSize === 0) {
  throw new Error('GetFileVersionInfoSizeW failed');
}

const versionInfoBuffer = Buffer.alloc(versionInfoSize);
const loaded = Version.GetFileVersionInfoW(filePath.ptr, 0, versionInfoSize, versionInfoBuffer.ptr);

if (loaded === 0) {
  throw new Error('GetFileVersionInfoW failed');
}

const fixedInfoPointerBuffer = Buffer.alloc(8);
const fixedInfoLengthBuffer = Buffer.alloc(4);
const rootSubBlock = Buffer.from('\\\0', 'utf16le');
const queried = Version.VerQueryValueW(versionInfoBuffer.ptr, rootSubBlock.ptr, fixedInfoPointerBuffer.ptr, fixedInfoLengthBuffer.ptr);

if (queried === 0) {
  throw new Error('VerQueryValueW failed');
}

const fixedInfoPointer = read.ptr(fixedInfoPointerBuffer.ptr);

if (fixedInfoPointer === null) {
  throw new Error('VerQueryValueW returned a null pointer');
}

const fixedInfoBuffer = Buffer.from(toArrayBuffer(fixedInfoPointer, 0, fixedInfoLengthBuffer.readUInt32LE(0)));
const fileVersionMajor = fixedInfoBuffer.readUInt16LE(10);
const fileVersionMinor = fixedInfoBuffer.readUInt16LE(8);
const fileVersionBuild = fixedInfoBuffer.readUInt16LE(14);
const fileVersionRevision = fixedInfoBuffer.readUInt16LE(12);

console.log(`Version resource: ${fileVersionMajor}.${fileVersionMinor}.${fileVersionBuild}.${fileVersionRevision}`);

AI agents: see AI.md for the package binding contract and source-navigation guidance. It explains how to use the package without scanning the entire implementation.

Examples

Run the included examples:

bun run example:file-version-audit
bun run example:version-skyline

Notes

• Either rely on lazy binding or call Version.Preload().
• Windows only. Bun runtime required.
• SAL types & naming: nullability is in the type — Optional<T> (formally optional, SAL _*opt_) and Nullable<T> (plain [in]/[out] the docs say can be NULL), the null sentinel derived from T (null for pointers LP*/P*, 0n for handles/by-value addresses); direction is in the parameter name — _out (_Out_), _in_out (_Inout_), _In_ bare. See AI.md and the repo AGENTS.md.