Release 1.3.0

macOS is now field-tested and working; the README platform notes say
so instead of untested. Linux remains audited-only.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

README.md

@@ -30,14 +30,14 @@ SWIG API. Requires KiCad **10.0.1+**.
 
 ## Setup (one-time)
 
-The plugin is developed and tested on **Windows**. **Linux and macOS
-are expected to work but are untested so far** — the code and the
-dependency stack have been audited for all three OSes (KiCad builds
-the plugin a private Python venv from `requirements.txt` on every
-platform, from pre-built wheels only, no compiler needed), but nobody
-has run the plugin there yet. Reports welcome! Steps 1–4 are the same
-everywhere; OS specifics are spelled out per step and in *Platform
-notes* below.
+The plugin is developed and tested on **Windows**; **macOS works**
+(field-tested on KiCad 10 after a round of mac-specific fixes).
+**Linux is expected to work but is untested so far** — the code and
+the dependency stack have been audited (KiCad builds the plugin a
+private Python venv from `requirements.txt` on every platform, from
+pre-built wheels only, no compiler needed), but nobody has run the
+plugin there yet. Reports welcome! Steps 1–4 are the same everywhere;
+OS specifics are spelled out per step and in *Platform notes* below.
 
 1. **Enable the API server**: KiCad → Preferences → Plugins → check
    *Enable KiCad API*.
@@ -78,15 +78,15 @@ notes* below.
 - **Windows** is the development and test platform — everything in
   this README was exercised here. KiCad's bundled Python is 3.13, so
   the venv gets the current dependency stack.
-- **macOS** — **untested** (audited only: dependency wheels, paths and
-  Python-version compatibility were checked, the plugin was never run
-  on a Mac). Requires macOS 12+ (KiCad's own minimum; Intel and Apple
-  Silicon — the dmg is universal). KiCad's bundled Python is **3.9**,
-  so pip resolves an older stack (numpy 2.0, scipy 1.13,
-  matplotlib 3.9, PySide6 6.9/6.10) that the plugin code is kept
-  compatible with. Expect plot and dialog windows to open **behind**
-  the KiCad window (they are raised best-effort) — check the Dock if
-  nothing seems to appear after a solve.
+- **macOS** — **works** (field-tested on KiCad 10). Requires
+  macOS 12+ (KiCad's own minimum; Intel and Apple Silicon — the dmg
+  is universal). KiCad's bundled Python is **3.9**, so pip resolves
+  an older stack (numpy 2.0, scipy 1.13, matplotlib 3.9,
+  PySide6 6.9/6.10); the plugin code is kept 3.9-compatible (guarded
+  by a test) and the suite is also run against that older stack.
+  Plot and dialog windows may open **behind** the KiCad window (they
+  are raised best-effort) — check the Dock if nothing seems to appear
+  after a solve.
 - **Linux** — **untested** (audited only, same caveat). The venv uses
   the system Python (3.9+), so the stack matches your distribution.
   On **ARM64 (aarch64)** there are no pyamg wheels —

docs/release-notes/v1.3.0.md

@@ -0,0 +1,42 @@
+The plugin now works on macOS. Results are unchanged from 1.2.2 for
+the same board and settings - nothing in the numerics was touched;
+this release is platform fixes and per-OS documentation.
+
+macOS (field-tested on KiCad 10):
+
+- Fixed a crash on launch. KiCad's macOS builds bundle Python 3.9,
+  and one module's type annotations were evaluated at import there
+  ("unsupported operand type(s) for |: 'type' and 'NoneType'"). The
+  plugin now runs on 3.9, and a test walks every shipped module so
+  the incompatibility cannot silently return.
+- Fixed every figure - the error figure included - refusing to render
+  with "Cannot load backend 'TkAgg' ... as 'qt' is currently
+  running". macOS' bundled Python ships tkinter, so matplotlib
+  preferred Tk while the selection dialog had already made the
+  process a Qt one. Qt (PySide6, a hard dependency) is now always
+  the first choice on every platform.
+- A board in a read-only location - such as the demo projects opened
+  straight from the mounted installer image - no longer kills the run
+  when the results directory cannot be created next to the board.
+  Results fall back to a temp directory and the path is printed to
+  the Messages panel.
+- The test suite additionally runs against the stack a Mac plugin
+  environment actually resolves (Python 3.9, numpy 2.0, scipy 1.13,
+  matplotlib 3.9, PySide6 6.10) - 140 tests on both stacks.
+
+Linux:
+
+- On ARM64 (aarch64) the plugin environment could never build: pyamg
+  publishes no wheels for that platform, KiCad installs wheels only,
+  and one unresolvable requirement fails the whole environment.
+  pyamg is now skipped there and the solver falls back to Jacobi-CG -
+  same results, noticeably slower on large grids. Linux as a whole
+  remains untested; reports welcome.
+
+Documentation:
+
+- Setup now gives dedicated instructions per operating system: which
+  interpreter path to check, how to deploy, and where the plugin's
+  Python environment lives on Windows, macOS and Linux (for the
+  delete-and-restart recovery). A platform-notes section records what
+  is actually tested on each OS and what to expect there.

metadata.json

@@ -17,7 +17,7 @@
     },
     "versions": [
         {
-            "version": "1.2.2",
+            "version": "1.3.0",
             "status": "stable",
             "kicad_version": "10.0",
             "runtime": "ipc"

pyproject.toml

@@ -3,7 +3,7 @@
 # the dependency list there in sync with [project.dependencies].
 [project]
 name = "fill-resistance"
-version = "1.2.2"
+version = "1.3.0"
 description = "DC resistance of copper zone fills and traces between two contacts (KiCad 10 plugin)"
 license = "GPL-3.0-or-later"
 requires-python = ">=3.11"

uv.lock

@@ -216,7 +216,7 @@ wheels = [
 
 [[package]]
 name = "fill-resistance"
-version = "1.2.2"
+version = "1.3.0"
 source = { virtual = "." }
 dependencies = [
     { name = "kicad-python" },