FrugalEDA: design suite for superconductor electronics
Harness the quantum properties of superconductivity.
FrugalEDA is a free, open-source design suite for energy-frugal superconductor electronics. It covers the whole workflow: schematic capture, netlist generation, SPICE simulation, optimisation and plotting. One installer sets everything up on macOS, Windows and Linux.

What’s inside
| Tool | Role | Description | Licence |
|---|---|---|---|
| LibrePCB | Schematic capture | A friendly, open-source schematic editor for your superconducting circuits. | GPL v3 (third party) |
| SuperLibre | Component library | Ready-to-use superconducting parts: Josephson junctions, inductors, logic cells. | CC0 1.0 |
| L2SPICE | Netlist export | Turns LibrePCB schematics into simulation-ready SPICE netlists in one click, with back-annotation. | Apache 2.0 |
| JOINUS-D | Design & optimisation | The main cockpit: edit, simulate, analyse and optimise your circuits. | Apache 2.0 |
| JSIM & JoSIM | Simulators | Two proven SPICE engines for Josephson-junction circuits, bundled and pre-configured. | Third party |
| FrugalPlot | Visualisation | Plot and compare results, set digital criteria with the mouse, export clean figures. | GPL v3 |
Who is it for?
- Students learning superconducting digital electronics.
- Researchers designing and optimising Josephson circuits.
- Teachers looking for a free, ready-to-install environment for courses and hands-on sessions.
- Engineers who need an accessible entry point before moving to industrial flows.
A short history
- 2017: the JOINUS project starts at Université Savoie Mont Blanc, supported by IARPA (ColdFlux/SuperTools).
- 2020: JOINUS is published in IEEE Transactions on Applied Superconductivity.
- 2023–2024: L2SPICE links the LibrePCB schematic editor to JOINUS.
- 2025: JOINUS-D, L2SPICE, FrugalPlot and SuperLibre join the FrugalEDA project, developed by SEFIRA with NGI0 Core funding.
- October 2026: FrugalEDA 1.0.0, the first all-in-one installer, for seven platforms.
How to cite
FrugalEDA developers, FrugalEDA: a design suite for energy-frugal superconductor electronics, version 1.0.0, 2026. https://gitlab.com/frugaleda/frugaleda-installer/-/releases/v1.0.0-release
S. Razmkhah and P. Febvre, “JOINUS: A User-Friendly Open-Source Software to Simulate Digital Superconductor Circuits,” IEEE Trans. Appl. Supercond., vol. 30, no. 5, 1300807, 2020. doi:10.1109/TASC.2020.2976600
