@byteink/mppjs

Convert Microsoft Project (.mpp) files to MSPDI XML from Node, Bun, or Deno. Native binary, no JVM required at runtime.

npx @byteink/mppjs project.mpp                  # → project.xml
npx @byteink/mppjs project.mpp out/result.xml

import { convert } from "@byteink/mppjs";

const { outputPath } = await convert("project.mpp", "out.xml");

Why

The standard tool for parsing .mpp is MPXJ (Java). @byteink/mppjs ships MPXJ as a GraalVM-AOT-compiled native binary, so you get the parser without Docker, without a JVM, without jpype/IKVM, and without a multi-second cold start.

Install

npm install @byteink/mppjs   # or pnpm add / yarn add / bun add

The native binary for your platform is delivered via an optionalDependencies sidecar (@byteink/mppjs-<platform>-<arch>). Supported targets:

| Platform | Sidecar package | | ------------- | -------------------------------- | | macOS arm64 | @byteink/mppjs-darwin-arm64 | | Linux x64 | @byteink/mppjs-linux-x64 | | Linux arm64 | @byteink/mppjs-linux-arm64 | | Windows x64 | @byteink/mppjs-win32-x64 |

If your platform isn't listed, open an issue.

API

import { convert, type ConvertOptions, type ConvertResult } from "@byteink/mppjs";

await convert(input: string, output?: string, options?: ConvertOptions): Promise<ConvertResult>

• input — path to .mpp, .mpx, or any format MPXJ understands
• output — path for the MSPDI XML; defaults to <input-without-ext>.xml
• options.binaryPath — override the bundled binary path (also via MPPJS_BINARY env var)
• options.timeoutMs — kill the spawned process after this many ms (default 60_000)

CLI

Usage: mppjs <input> [output.xml]

Exit codes: 0 ok, 1 conversion failure, 2 usage/IO error.

Building from source

Requires Liberica NIK 23.1.x (or any GraalVM JDK 21 distribution including native-image) and Maven 3.9+.

git clone https://github.com/byteink/mppjs
cd mppjs
npm install
npm run build              # jar → native binary → tsc
npm test                   # via bun, against MPXJ sample files

The native-image build takes 5–8 minutes on a modern laptop.

See CLAUDE.md for architecture details, including how the reflection metadata under .ni-config/ is regenerated when MPXJ is upgraded.

License

• The TypeScript wrapper (this package) is MIT.
• The platform-specific binaries shipped via @byteink/mppjs-<platform> sidecars contain MPXJ and are LGPL-2.1-or-later. Each sidecar package includes the LGPL text and a NOTICE pointing to the upstream source.

The wrapper invokes the binary as a subprocess; LGPL obligations are contained to the sidecar packages.