Fang
Hardware as code toolchain under Copperhead: a Python embedded language and design graph kernel with units, interfaces and constraints that lowers designs to netlists, views, simulation decks and CAD.
What it does and how it connects
Fang is a hardware-as-code toolchain and the language and kernel under Copperhead. It is a Python-embedded language for authoring hardware, a typed kernel that holds the design, and compilers that lower it into netlists, views, simulation decks, and CAD.
Designs are written as Python classes with typed interfaces, units, pin maps, and constraints. The example sensor board shows an MCU and IMU connected over I2C with candidate pins recorded as decisions, and a regulator constraint requiring 3.3 V output. The CLI offers fang build, check, netlist, export to a KiCad netlist, view, sim, verify, emulate in Renode, and an MCP server mode.
Per issue 19, the package is not on PyPI, so pip install copperhead-fang fails; the install instructions use an editable source install instead. Firmware emulation covers Renode.
What engineers report
pip install copperhead-fang fails: the package is not on PyPI, so the install command in the README fails.
2026-10-06Read the original
Alternatives
Compare side by side- atopile
A code-first language and compiler for electronics, rather than a Python-embedded language and design graph kernel under Copperhead.
- copperhead
The CLI agent that Fang sits under: it edits existing KiCad schematic and PCB files directly, with ERC and DRC verification.
- tscircuit
Designs boards in TypeScript and React (TSX) in a browser or CLI workflow, rather than in a Python-embedded hardware language.
- kicad-tools (rjwalters)
Standalone Python tools for AI agents to parse and manipulate KiCad files, with an autorouter and an MCP server.
Recurring errors it addresses
Error Index entries this tool is built to reduce or work around.
- Interactive routing creates unwanted micro-segments and awkward paths that take time to clean up.Error Index
- Grid snap and move commands can disconnect items or reposition them in unwanted ways.Error Index
- GUI lag, occasional freezes, and sluggish editor switching interrupt concentration.Error Index
- Wayland/NVIDIA users report graphical glitches, flicker, or instability.Error Index
Sources
Not verified
- No GitHub releases exist, so latest release fields are null.
- Pricing: none stated on the repo.
- Activity: last push October 2026; the package is not on PyPI, so installation is from source.
- A named individual builder beyond the repository owner organization copperheadhq
Last verified November 6, 2026. Listings are informational. The evidence score measures public, verifiable evidence and is not an endorsement or a compatibility claim.