MDEngine

An agent-first molecular dynamics workbench for macOS — a Metal trajectory viewer, a command-line tool, and an MCP server that lets AI agents run LAMMPS simulations and see the results.

Download for Mac View on GitHub

Oxygen atoms depositing onto an aluminum slab, rendered as an animated trajectory — Aluminum oxidation — simulated with LAMMPS, submitted, tracked, and rendered to video entirely through MDEngine’s agent tools.

For humans

A native Mac app, not an Electron shell. Open any XYZ, extended-XYZ, or LAMMPS dump and it renders in a Metal viewer with an orbit / pan / zoom camera, CPK element colours, a scrubbing timeline, and per-element size and colour controls.

Follows live simulations. The readers are safe on in-flight dumps — open a file your simulation is still writing and inspect the completed frames mid-run.
Double-click to open. .xyz, .lammpstrj, and .traj files open straight from Finder.
A real CLI. mdengine info / export / decimate / run for scripted work on trajectories and decks.

For agents

MDEngine ships a dependency-free MCP stdio server. Connect it to Claude (or any MCP client) and the agent can drive the whole loop: submit a LAMMPS deck as a detached background job, poll its live thermo output, analyze the trajectory, and render frames or video to actually look at what happened.

Detached job runner — submit_lammps jobs survive the server exiting and the machine’s display sleep; exit codes are recorded unattended.
Vision for the loop — render_image and render_video turn any frame or trajectory into a PNG, MP4, or GIF the agent can inspect. The clip above was made this way.
Analysis primitives — trajectory_info, z_profile (deposition depth, surface plane, bound-probe charge), export_frame with charges, decimate.

claude mcp add mdengine /path/to/.build/release/mdengine-mcp

A submitted deck runs with your user’s privileges — LAMMPS decks are programs, not data. Read the security note before handing the job runner to an agent.

Get it

MDEngine 0.6.1 for Mac — Download the DMG (2.3 MB), open it, drag MDEngine to Applications. Signed and notarized by Gitinama Inc.; macOS 14+, Apple silicon. LAMMPS (brew install lammps) is needed only to run simulations, not to view trajectories.

CLI + MCP server — mdengine-tools-0.6.1-macos-arm64.tar.gz: the mdengine command and mdengine-mcp stdio server, signed and notarized. Unpack anywhere and point your agent at mdengine-mcp.

From source — macOS 14+ and Xcode command-line tools:

git clone https://github.com/forcefieldsilicon/mdengine
cd mdengine
swift build -c release        # viewer, CLI, and MCP server
./scripts/make_app.sh         # installs /Applications/MDEngine.app

Checksums and release notes: v0.6.1 on GitHub.

Run it on our GPU

CPU runs on your own Mac are free, forever. When a run would pin your laptop for days, send the same deck to our NVIDIA GPU instead: mdengine run --gpu deck.in in the CLI, or Run › Run accelerated in the app. Correct KOKKOS build, ReaxFF and EAM ready, checkpointed, results land back in the same job list and open in the viewer. Nothing to install, nothing to babysit.

$2.00 per GPU-hour, billed per second (1-minute minimum) from a prepaid balance. You set a wall-time cap when you submit and you can never be charged past it; the CLI and app show the cap in dollars before you confirm and the projected cost while it runs. Typical: an EAM melt/quench at 50k atoms ≈ $3 · a ReaxFF oxide growth to a paper-grade film ≈ $60. Launch overhead isn’t billed; a run that fails on our side is refunded.

Starter

$25

12.5 GPU-hours — roughly 40 laptop-hours of ReaxFF. Enough to run your first real job and decide. Launch code FIRSTGPU takes 50% off (first 20).

Buy Starter

Lab

$100

50 GPU-hours. A paper’s worth of deposition or oxidation runs, or a semester of EAM coursework, on one key.

Buy Lab

Group

$500

275 GPU-hours (10% bonus) plus priority in the queue. One balance a whole group draws from; business name and tax ID on the receipt.

Buy Group

Credits never expire. Your API key appears on screen the moment checkout completes; paste it once with mdengine login or in the app’s Settings and every surface shares the balance. GPU runners are open now — buy, paste the key, run. Speedup is honest, not marketed: one RTX 4090 is 1.4× an M2 Pro at 2k atoms and 3.3× at 38k; what you buy is your laptop back and a run that finishes unattended.

Your data. Decks and trajectories travel over TLS and sit encrypted at rest in object storage, are deleted 30 days after the run, and are never used for anything else. Each job runs in a network-isolated sandbox on a machine that exists only for the duration of your job. One person has operator access. Questions: arvand@gitinama.tech. ForceField Silicon is a trade name of Gitinama Inc.

Docs

The README covers all three tools, the bundled example decks (a Lennard-Jones argon melt and a ReaxFF iron oxidation), and the full MCP tool table. The app ships with its manual under Help → MDEngine Manual.