Attempt to compile against Vial too

.github/workflows/build_vial_binaries.yaml

@@ -0,0 +1,21 @@
+name: Build Vial firmware
+
+on: [push, workflow_dispatch]
+
+permissions:
+  contents: write
+
+jobs:
+  build:
+    name: 'Vial Userspace Build'
+    uses: qmk/.github/.github/workflows/qmk_userspace_build.yml@main
+    with:
+      qmk_repo: vial-kb/vial-qmk
+      qmk_ref: vial
+      preparation_command: 'cp vial.json qmk.json && for KB in "$GITHUB_WORKSPACE/keyboards/*/"; do ln -s $KB qmk_firmware/keyboards/ ; done'
+
+  publish:
+    name: 'Vial Userspace Publish'
+    uses: qmk/.github/.github/workflows/qmk_userspace_publish.yml@main
+    if: always() && !cancelled()
+    needs: build

README.md

@@ -8,7 +8,7 @@ so that I can experiment with layouts without the overhead of the full
 [QMK firmware repository](https://github.com/qmk/qmk_firmware/).
 
 I am also using this to host QMK firmware for any of my own keyboard PCBs (with a
-[tweak](/.github/workflows/build_binaries.yaml) to the GitHub Actions
+[tweak](.github/workflows/build_binaries.yaml) to the GitHub Actions
 `preparation_command` to compile these online):
 
 * [Tutte-Coxeter 36k](keyboards/tutte_coxeter_36k/readme.md) - my no-diode single
@@ -16,6 +16,11 @@ I am also using this to host QMK firmware for any of my own keyboard PCBs (with
   avoid ghosting. This has a sparse 13x13 scanning matrix (using 26 GPIO pins)
   for 36 keys with 6-key rollover (the USB HID limit).
 
+In a further complication, the GitHub Actions setup is duplicated to
+[compile my Vial layouts](.github/workflows/build_vial_binaries.yaml) against
+the Vial fork of the QMK firmware repository. This uses [vial.json](vial.json)
+rather than [qmk.json](qmk.json) to list the layouts to build.
+
 # QMK Userspace
 
 This is a template repository which allows for an external set of QMK keymaps to be defined and compiled. This is useful for users who want to maintain their own keymaps without having to fork the main QMK repository.

vial.json

@@ -0,0 +1,6 @@
+{
+    "userspace_version": "1.1",
+    "build_targets": [
+        ["tutte_coxeter_36k", "vial"]
+    ]
+}