SuperSlice

A small REST API for 3D print estimation. POST an STL or 3MF file and get back the print time and filament usage a slicer would report — as JSON — so your own app doesn't have to run a slicer. It does one thing: estimate. Pricing, orders, and UI are left to the app that calls it.

It works by invoking PrusaSlicer headlessly and parsing the result.

How it works

flowchart LR
    app["Your app"] -->|"POST /slice + parameters"| ss["SuperSlice"]
    ss -->|"runs headless"| ps["PrusaSlicer CLI"]
    ps -->|"G-code"| ss
    ss -->|"JSON estimate"| app

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1. You upload an STL/3MF with the parameters you control: layer height, infill density, wall count, and filament.

2. SuperSlice runs PrusaSlicer headlessly on it — the same engine as the desktop app — producing real G-code.

3. It reads the summary PrusaSlicer writes into that G-code:

   ; estimated printing time (normal mode) = 19m 22s
   ; filament used [mm]  = 1506.53
   ; filament used [cm3] = 3.62
   

   then computes weight from filament density and returns JSON.

4. The upload and G-code are deleted immediately; nothing about your model is kept unless you enable history.

The numbers match what PrusaSlicer itself reports; accuracy depends on the slicer profile (see docs/ACCURACY.md).

Why PrusaSlicer 2.8.1?

It's pinned deliberately. PrusaSlicer 2.9+ is distributed for Linux as a Flatpak only — it now depends on WebKitGTK, which is impractical to bundle in a slim container — so 2.8.1 is the last release available as a self-contained Linux AppImage, and it runs cleanly headless with no display or GPU.

Quick start

Run the published image:

docker run -d --name superslice -p 8000:8000 \
  ghcr.io/bintangtimurlangit/superslice:latest

Or build from source: docker compose up --build. Either way the API is at http://localhost:8000 (interactive docs at /docs).

Slice a model:

curl -X POST http://localhost:8000/slice \
  -F "file=@model.stl" \
  -F "layer_height=0.2" -F "infill_density=20" -F "wall_count=3" \
  -F "filament_type=PLA"

{
  "success": true,
  "print_time_formatted": "45m 30s",
  "print_time_minutes": 45.5,
  "filament_length_mm": 1234.56,
  "filament_volume_cm3": 2.98,
  "filament_weight_g": 3.69,
  "filament_type": "PLA"
}

→ Full endpoints, parameters, and error codes: docs/API.md. Prefer a GUI? Import the Postman collection at docs/superslice.postman_collection.json.

Documentation

Doc	What's in it
API.md	Endpoints (incl. async jobs & history), parameters, auth, errors
CONFIGURATION.md	Environment variables (incl. auth, rate limit, history)
DEPLOYMENT.md	Running the image: Compose, reverse proxy, cloud
ARCHITECTURE.md	How it's built and how an estimate is produced
ACCURACY.md	How realistic the numbers are, and how to improve them
TROUBLESHOOTING.md	Common issues

Upcoming

Planned next (not built yet):

• Printer & filament presets — pick a bundled PrusaSlicer profile so estimates track a specific machine. This is the main accuracy lever.
• Energy estimate — optional wattage from a printer preset.

Already shipped: build-plate fit (fits_build_volume, default 256×256×256), requires_supports, and the model bounding box are in every /slice response.

Out of scope by design: pricing, orders, and any UI. Those are built by the app that calls SuperSlice (for example a 3D-printing website), not by SuperSlice itself — it only returns the estimate.

Local development

The app is a small FastAPI package; it needs a PrusaSlicer binary on the host.

python -m venv .venv && source .venv/bin/activate
pip install -r requirements-dev.txt
export PRUSASLICER_PATH=/path/to/prusa-slicer
export UPLOAD_DIR=./uploads OUTPUT_DIR=./output
uvicorn app.main:app --reload   # run from the repo root
pytest                          # run the tests (slicer is mocked)

See CONTRIBUTING.md for conventions and RELEASING.md for the release process.

License & attribution

SuperSlice's own code is MIT — use it freely, including commercially.

It bundles an official, unmodified build of PrusaSlicer 2.8.1 (AGPL-3.0), which it invokes as a separate program; corresponding source. The distributed image as a whole therefore contains AGPL-3.0 software — keep this attribution if you redistribute it. "PrusaSlicer" and "Prusa" are trademarks of Prusa Research a.s.; SuperSlice is not affiliated with them.