fabprint 0.1.39

Immutable 3D print pipeline: arrange, slice, and print

fabprint

Immutable 3D print pipeline: arrange parts on a build plate, slice to gcode, and send to a Bambu Lab printer — all defined in a single TOML config file.

Why fabprint?

Code-CAD tools like build123d, OpenSCAD and cadquery let you define physical parts in code — making designs parametric, testable, and version-controlled. But the moment you need to print, that workflow breaks: open a slicer GUI, drag in files, fiddle with settings, hit print. Hard to reproduce, no diffs, the only thing to track are binary project files.

fabprint is aiming to close that gap. Define your objects, filaments, slicer setting and printer targets in a straightforward TOML file. Use a CLI or CI pipeline to arrange, slice and send to the printer. Pin filament and printer profiles to capture the exact settings. Slicing happens in Docker for platform-agnostic reproducible builds. Everything is text, everything goes in git, and the same config produces the same print every time.

Quick start

1. Install

pip install fabprint

2. Create fabprint.toml

[plate]
size = [256, 256]       # build plate dimensions in mm
padding = 5.0

[slicer]
engine = "orca"
printer = "Bambu Lab P1S 0.4 nozzle"
process = "0.20mm Standard @BBL X1C"

[[parts]]
file = "frame.stl"
filament = "Generic PETG-CF @base"

[[parts]]
file = "wheel.stl"
copies = 5
orient = "upright"
filament = "Generic PETG-CF @base"

Parts reference filament profiles by name — no need to manually number AMS slots.

3. Arrange, slice, print

fabprint plate fabprint.toml -o plate.3mf   # arrange parts onto a build plate
fabprint slice fabprint.toml                 # arrange and slice to gcode
fabprint print fabprint.toml                 # arrange, slice and send to printer

The plate command also generates a plate_preview.3mf with a bed outline — open it in any 3MF viewer to review placement:

Features

• Multi-format input — STL, 3MF, and STEP files
• Automatic orientation — flat, upright, side, or custom rotations
• Bin packing — efficient 2D arrangement with configurable padding
• Part scaling — uniform scale factor per part
• Multi-filament — AMS slot assignment per part with correct extruder mapping
• Slicer integration — OrcaSlicer support
• Profile management — discover, pin, and override slicer profiles
• Print delivery — LAN, Bambu Connect, or cloud API
• Docker support — pre-built images with OrcaSlicer for reproducible CI/CD slicing
• Cross-platform — macOS, Linux, and Windows

Installation

Requires Python 3.11+.

pip install fabprint

Or with uv:

uv pip install fabprint

Optional extras

pip install "fabprint[lan]"    # LAN printing via MQTT/FTP
pip install "fabprint[cloud]"  # Bambu Cloud API (experimental)
pip install "fabprint[step]"   # STEP file support (build123d)
pip install "fabprint[all]"    # Everything

CLI reference

fabprint plate <config>                     # Arrange and export 3MF (+ preview)
fabprint slice <config>                     # Arrange, export, and slice to gcode
fabprint print <config>                     # Arrange, slice, and send to printer
fabprint print <config> --dry-run           # Do everything except send to printer
fabprint print <config> --gcode plate.gcode # Send pre-sliced gcode
fabprint print <config> --upload-only       # Upload without starting print
fabprint print <config> --sequence 1        # Print only sequence 1
fabprint gcode-info plate.gcode             # Analyze extruder usage per layer
fabprint login                              # Log in to Bambu Cloud, cache token
fabprint watch                              # Live dashboard for all printers 
fabprint status                             # Query status of all printers
fabprint profiles list                      # List available slicer profiles
fabprint profiles pin <config>              # Pin profiles for reproducible builds

Config reference

[printer]

Key	Type	Default	Description
mode	string	"bambu-lan"	"bambu-lan", "bambu-connect", or "bambu-cloud"
ip	string	—	Printer IP address (LAN mode)
access_code	string	—	Printer access code (LAN mode)
serial	string	—	Printer serial number (LAN mode)

Printer modes:

• bambu-lan — Direct LAN connection via MQTT + FTP. Requires ip, access_code, and serial. Fastest, works offline.
• bambu-connect — Sends sliced .gcode.3mf to the Bambu Connect app. No credentials needed; you confirm and start from the app.
• bambu-cloud — Experimental cloud API. Requires BAMBU_EMAIL and BAMBU_PASSWORD env vars.

Environment variable overrides:

Env var	Overrides
BAMBU_PRINTER_IP	printer.ip
BAMBU_ACCESS_CODE	printer.access_code
BAMBU_SERIAL	printer.serial
BAMBU_EMAIL	Cloud login email
BAMBU_PASSWORD	Cloud login password

[plate]

Key	Type	Default	Description
size	[w, h]	—	Build plate size in mm
padding	float	5.0	Gap between parts in mm

[slicer]

Key	Type	Default	Description
engine	string	"orca"	"orca" or "bambu"
version	string	—	Required OrcaSlicer version (e.g. "2.3.1")
printer	string	—	Printer profile name
process	string	—	Process profile name
filaments	[string]	—	Filament profiles (auto-derived from parts if omitted)

[slicer.slots]

Map slot numbers to filament profiles for explicit AMS placement:

[slicer.slots]
1 = "Generic PLA @base"
3 = "Generic PETG-CF @base"
5 = "Generic TPU @base"        # direct feed (bypass AMS)

Parts can use filament = 3 to target a specific slot, or filament = "Generic PLA @base" to auto-assign.

[slicer.overrides]

Key-value pairs applied on top of the process profile:

[slicer.overrides]
enable_support = 1
wall_loops = 4
curr_bed_type = "Textured PEI Plate"

Common bed types: "Cool Plate", "Engineering Plate", "High Temp Plate", "Textured PEI Plate".

[[parts]]

Key	Type	Default	Description
file	string	—	Path to mesh file (STL/3MF/STEP)
copies	int	1	Number of copies
orient	string	"flat"	"flat", "upright", or "side"
rotate	[x, y, z]	—	Custom rotation in degrees (overrides orient)
filament	int|string	1	Filament profile name or slot index
scale	float	1.0	Uniform scale factor
object	string	—	Select a named object from a multi-object 3MF
sequence	int	1	Print order for sequential printing

[parts.filaments]

Per-object filament overrides for multi-object 3MF files:

[[parts]]
file = "widget.3mf"
filament = "Generic PETG-CF @base"       # default for objects not listed

[parts.filaments]
inlay = "Bambu PLA Basic @BBL X1C"       # override for object named "inlay"

Objects are grouped as a single unit for bin packing.

Sequential printing

For workflows like bottom inlay printing — print one object first (e.g. text inlay in PLA), then print the body on top (e.g. PETG-CF):

[[parts]]
file = "widget.3mf"
object = "inlay"
filament = "Generic PLA @base"
sequence = 1

[[parts]]
file = "widget.3mf"
object = "body"
filament = "Generic PETG-CF @base"
sequence = 2

Both objects come from the same 3MF, so fabprint guarantees identical bed positioning:

fabprint print fabprint.toml --sequence 1   # print the inlay
# wait for completion...
fabprint print fabprint.toml --sequence 2   # print the body on top

Profile management

fabprint resolves slicer profiles in this order:

1. Direct file path (if the name contains / or \)
2. Pinned profiles in <project>/profiles/<category>/
3. Slicer system directory

Pin profiles to lock your build against slicer updates:

fabprint profiles pin fabprint.toml

Commit the profiles/ directory to git for identical slicing across machines.

Docker

Pre-built images with OrcaSlicer are available on Docker Hub:

docker pull fabprint/fabprint:orca-2.3.1

Run from your project directory:

docker run --rm -v "$PWD:/project" fabprint/fabprint:orca-2.3.1 slice fabprint.toml
docker run --rm -v "$PWD:/project" fabprint/fabprint:orca-2.3.1 plate fabprint.toml -o plate.3mf

By default, fabprint uses Docker if available, falling back to a local slicer install:

fabprint slice fabprint.toml                  # Docker first, local fallback
fabprint slice fabprint.toml --local          # Force local slicer
fabprint slice fabprint.toml --docker-version 2.3.1  # Pin Docker image version

For fully reproducible builds, pin both profiles and the OrcaSlicer version:

fabprint profiles pin fabprint.toml
fabprint slice fabprint.toml --docker-version 2.3.1

To build your own image:

./scripts/build-docker.sh 2.3.2          # build only
./scripts/build-docker.sh 2.3.2 --push   # build and push

Platform support

fabprint auto-detects slicer paths per platform:

Platform	BambuStudio	OrcaSlicer
macOS	/Applications/BambuStudio.app/...	/Applications/OrcaSlicer.app/...
Linux	/usr/bin/bambu-studio	/usr/bin/orca-slicer
Windows	C:\Program Files\BambuStudio\...	C:\Program Files\OrcaSlicer\...

Slicers on PATH are also detected (Flatpak, Snap, custom installs). Profile directories follow platform conventions (~/Library/Application Support/ on macOS, ~/.config/ on Linux, %APPDATA% on Windows).

How it works

1. Arrange — loads meshes, orients them, and bin-packs onto the build plate
2. Export — writes a 3MF with per-object extruder metadata for correct AMS slot mapping
3. Slice — calls OrcaSlicer CLI to produce a Bambu Connect-compatible .gcode.3mf
4. Post-process — patches the sliced 3MF to fix metadata issues Bambu Connect requires (see docs/gcode-3mf-format.md)
5. Send — delivers to the printer via LAN, Bambu Connect, or cloud API

Contributing

git clone https://github.com/pzfreo/fabprint.git
cd fabprint
uv sync --extra dev
uv run pytest              # run tests
uv run ruff check src tests     # lint
uv run ruff format src tests    # format

License

Apache 2.0