GDSFactory

9.40.1 · active · verified Fri Apr 17

gdsfactory is a Python library for generating GDS layouts, primarily used in photonics and electronics design. It provides a robust framework for creating parametric cells, routing, and packaging complex circuits into GDSII format. The current version is 9.40.1, and it maintains a rapid release cadence with frequent updates and new features.

Common errors

```
ModuleNotFoundError: No module named 'gdsfactory'
```
cause The `gdsfactory` package is not installed in the active Python environment.

fix Install the package using pip: `pip install gdsfactory`. Ensure your IDE or script uses the correct Python interpreter where it's installed.
```
ImportError: cannot import name 'Component' from 'gdsfactory.component'
```
cause This import path was common in older GDSFactory versions (e.g., pre-v7). In current versions, `Component` is directly available from the top-level `gdsfactory` module.

fix Change `from gdsfactory.component import Component` to `from gdsfactory import Component` or, more commonly, use `import gdsfactory as gf` and access it via `gf.Component`.
```
TypeError: __init__() got an unexpected keyword argument 'name'
```
cause This error often indicates a Pydantic version incompatibility. GDSFactory v9+ requires Pydantic v2, but Pydantic v1 might be installed in your environment, leading to API mismatches during object initialization.

fix Upgrade Pydantic to version 2: `pip install "pydantic>=2.0.0,<3.0.0"`. Verify that any custom Pydantic models you use are compatible with Pydantic v2.

Warnings

breaking GDSFactory v9+ has a strict dependency on Pydantic v2. If your project uses Pydantic v1 for other purposes, you may encounter compatibility errors due to API changes between Pydantic versions.
Fix: Ensure your environment has `pydantic>=2.0.0,<3.0.0` installed. If you have custom Pydantic models, they might need migration to Pydantic v2 syntax.
deprecated The method `Component.add_ref()` is deprecated. The preferred and more idiomatic way to add references to a component is now `parent_component << child_component`.
Fix: Replace `c.add_ref(my_component)` with `c << my_component` for cleaner and more Pythonic code.
gotcha Using `gf.show()` or `component.show()` to visualize GDS layouts requires Klayout to be installed and properly configured in your system's PATH, or by setting the `GDSFACTORY_KLAYOUT_PATH` environment variable. Without this, the `show()` function may fail to open the GDS viewer.
Fix: Install Klayout (a free GDS viewer) and add its executable directory to your system's PATH. Alternatively, set an environment variable `GDSFACTORY_KLAYOUT_PATH` to the full path of the Klayout executable.

Install

pip install gdsfactory Install latest stable version

Imports

gdsfactory
```
import gdsfactory as gf
```
Component
wrong:
```
from gdsfactory.component import Component
```
correct:
```
from gdsfactory import Component
```
The Component class moved to the top-level namespace from `gdsfactory.component` in earlier versions.

Quickstart

This quickstart demonstrates how to create a basic GDSFactory component, add a standard straight waveguide, and export it to a GDSII file. Ensure you have GDSFactory installed before running.

import gdsfactory as gf

# Create a new component
c = gf.Component("my_first_device")

# Add a straight waveguide to the component
waveguide = c << gf.components.straight(length=10, width=0.5)

# Optionally, rotate the waveguide
waveguide.rotate(45)

# Write the component to a GDSII file
c.write_gds("my_first_device.gds")

print(f"Generated GDS file: {c.name}.gds")

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