Editing and Persistence

Rosette uses one authoritative representation at a time. The viewer shows the current mode in its status bar.

Live Python previews

rosette serve executes arbitrary Python and lowers components, routes, loops, helpers, and geometry operations into a layout. The resulting polygons do not contain enough information to identify which Python expression should change. Rosette therefore does not attempt unrestricted geometry-to-Python round trips.

While the status bar says Python source, layout mutations are disabled. You can still:

• inspect and select geometry;
• navigate cells and control layer visibility;
• pan, zoom, and use the minimap;
• create and edit measurement rulers;
• inspect DRC violations; and
• export screenshots or the current geometry as GDS.

Saving the Python file re-executes the design and replaces the preview. Because the preview cannot accumulate layout edits, a reload cannot silently discard them.

Edit a copy

Choose Edit a copy to make the currently rendered layout an app-owned document. This closes the live-update connection before editing is enabled, so later Python saves cannot replace the copy.

The transition is intentionally one-way. Changes to the detached document do not update the Python file. Run rosette serve again to return to the live source-backed design.

Save and export

The artifact name in the action describes what Rosette writes:

• Save GDS writes an app-owned GDS document in the desktop app.
• Export GDS serializes the current geometry. It does not save Python, measurement rulers, image annotations, or DRC state.
• Export Screenshot writes the current visual viewport.
• rosette build design.py executes Python and writes the resulting GDS.

GDS is an interchange and fabrication format, not a lossless representation of Python design intent. Keep Python source under version control when it is the authoritative design.

Constrained source edits

Future source editing may support operations that can be represented as an unambiguous semantic intent, such as changing a literal component argument or moving a top-level instance with known provenance. Such edits must detect source conflicts, preview the code diff, re-execute the design, and fail closed when the mapping is ambiguous.