License review
This is an engineering inventory, not legal advice. Redistribution of GPL/LGPL components and vendor tools requires professional legal review before any public release.
FalCAD’s own code
- Application, engines, CLI, SDK, toolchain manifests: Apache-2.0.
- Documentation prose: CC BY 4.0. Code samples in the docs: Apache-2.0.
- The hosted service, infrastructure and product repositories: proprietary.
- The FalCAD name and logo aren’t covered by the open-source licenses. A brand-use policy will follow trademark clearance. The name and domains aren’t yet cleared or owned.
Bundled or shipped third-party components
| Component | Used by | License | Notes |
|---|---|---|---|
| React, React DOM | app | MIT | |
| Monaco editor | app | MIT | transitive DOMPurify pinned to a patched version |
| three.js | app | MIT | |
| Lucide icons | app | ISC (some icons MIT, from Feather) | notices in the app’s THIRD_PARTY_NOTICES.md |
| Inter, JetBrains Mono | app | SIL OFL 1.1 | embedded in the application only |
| intl-messageformat | app | BSD-3-Clause | |
| zod, fflate | format | MIT | |
| avr8js | mcu | MIT | |
| @yowasp/yosys, @yowasp/nextpnr-ice40 | hdl | ISC (upstream Yosys, nextpnr, IceStorm); bundled ABC (permissive), MiniSat (MIT), slang (MIT) | published packages lack a LICENSE file; full upstream texts must be collected before redistribution |
| earcut | pcb | ISC | |
| polygon-clipping (+ robust-predicates, splaytree) | pcb | MIT (+ Unlicense, MIT) | |
| @modelcontextprotocol/sdk | cli | MIT | |
| Electron (Chromium, Node) | desktop | MIT + Chromium notices | Chromium’s license file ships with the app |
Detected, not bundled (pending review before any bundling)
ngspice, Icarus Verilog, GHDL, Verilator, native Yosys and nextpnr, openFPGALoader, arduino-cli, avr-gcc and binutils, avrdude, arm-none-eabi-gcc, OpenOCD, pyOCD, GTKWave. The per-tool record (SPDX, packaging class, redistribution status, obligations) is the license ledger in falcad-toolchains.
Open questions for legal review
- Bundling GPL-licensed tools (e.g. Icarus Verilog, GHDL, avr-gcc, OpenOCD) as separate executables inside the desktop installer: source-offer obligations and installer layout.
- Redistributing the YoWASP WebAssembly builds in installers and the web app: notice requirements for every bundled upstream component.
- Microchip XC compilers: licenses were announced free of charge (July 2026), but free use doesn’t mean redistribution rights. FalCAD will detect and guide installs only.
- Trademark clearance for “FalCAD” and the planned domains.