How to Merge Multiple OpenSCAD (.scad) Files Into One

Why split OpenSCAD into multiple files?

A single 6,000-line .scad file is hard to navigate, review, and reuse. Teams split projects into:

• Entry file (main.scad) — customizer parameters and top-level assembly
• Library modules (lib/*.scad) — reusable geometry, bolts, hinges, text
• Part files — one module per printable component

OpenSCAD links files with use <path/file.scad> (imports modules/functions) and include <path/file.scad> (inlines entire file). That works locally — until you need one merged file for upload.

How to manually combine multiple .scad files

The traditional approach:

1. Open each dependency in order of the include tree.
2. Copy module definitions into one file, avoiding duplicates.
3. Remove nested use lines or replace them with inlined code.
4. Keep customizer annotations (/* [Group] */) only in the entry file.

// main.scad — entry
use <lib/base.scad>
use <lib/lid.scad>

width = 40; // [20:80]
base(width);
lid(width);

This breaks quickly with circular references, BOSL2-style libraries, and MakerWorld's single-file customizer requirement.

Why copy-paste merging fails at scale

• Duplicate symbols — the same module defined in two branches of the tree
• Wrong include order — functions used before they are defined
• Path drift — use <lib/foo.scad> breaks when flattened to one directory
• Customizer pollution — parameters scattered across merged files confuse the UI
• No diff — you lose the link between source modules and the upload artifact

You need an OpenSCAD packer — a tool that parses the dependency graph and emits one validated monolith. That is exactly what ScadPack does.

Merge OpenSCAD files with ScadPack (free browser IDE)

ScadPack is a project-first OpenSCAD IDE: multi-file explorer, live WASM render, AI coding agent, and a monolithic packer built for MakerWorld uploads.

Step 1 — Import your project

Open scadpack.app, click Add files or Open folder, and select all .scad files. Existing tabs are preserved — nothing is wiped.

Step 2 — Set the entry file

Mark which file is the entry (usually main.scad). Customizer variables should live there.

Step 3 — Pack

Click Pack. ScadPack resolves every use and include, deduplicates modules, and produces packed.scad — one file ready for export. Preview updates automatically.

Step 4 — Export

Download the packed file or copy it into MakerWorld's customizer. Use the MakerWorld profile so bundled libraries (BOSL2, etc.) stay as imports where the platform expects them.

Combine SCAD files from the command line

For CI pipelines and automated MakerWorld releases:

npm install -g @scadpack/cli

# Pack entire project → single file
scadpack --profile makerworld -e main.scad -o dist/model.scad ./my-project

# Validate before upload
scadpack --validate -e main.scad ./my-project

Pair with GitHub Actions to repack on every tag and upload to MakerWorld without manual merging.

MakerWorld & Bambu Lab customizer checklist

After you merge OpenSCAD files into one upload:

1. Keep all customizer parameters in the entry file only
2. Use the makerworld pack profile (not full monolithic) if you rely on platform libraries
3. Render locally in ScadPack (F5) before export — catch CSG errors early
4. Test parameter sliders match your intended ranges
5. Upload the packed output, not the multi-file source tree

Read our dedicated MakerWorld OpenSCAD guide for profile details.

Frequently asked questions

Related guides

• OpenSCAD inliners — inline modular SCAD online
• OpenSCAD packer — online monolithic export
• OpenSCAD for MakerWorld customizers
• Public Alpha — free during launch